[gtk/wip/baedert/gtkimageview] WIP: Add GtkImageView



commit c4d4c16b121008ab6766c0eb6aa4fad0b2e7b2f8
Author: Timm Bäder <mail baedert org>
Date:   Sat Mar 24 20:54:27 2018 +0100

    WIP: Add GtkImageView

 demos/gtk-demo/demo.gresource.xml    |    4 +
 demos/gtk-demo/image_view.c          |  258 ++++
 demos/gtk-demo/image_view.ui         |  313 +++++
 demos/gtk-demo/meson.build           |    1 +
 docs/reference/gtk/gtk4-docs.xml     |    1 +
 docs/reference/gtk/gtk4-sections.txt |   39 +
 docs/reference/gtk/gtk4.types.in     |    1 +
 docs/reference/gtk/visual_index.xml  |    3 +
 gdk/gdkpaintable.h                   |    2 +-
 gtk/gtk.h                            |    1 +
 gtk/gtkimageview.c                   | 2179 ++++++++++++++++++++++++++++++++++
 gtk/gtkimageview.h                   |  116 ++
 gtk/meson.build                      |    2 +
 testsuite/gtk/imageview-size.c       |  178 +++
 testsuite/gtk/meson.build            |    1 +
 15 files changed, 3098 insertions(+), 1 deletion(-)
---
diff --git a/demos/gtk-demo/demo.gresource.xml b/demos/gtk-demo/demo.gresource.xml
index 625ecac18a..4c5035335d 100644
--- a/demos/gtk-demo/demo.gresource.xml
+++ b/demos/gtk-demo/demo.gresource.xml
@@ -186,6 +186,7 @@
     <file>iconview.c</file>
     <file>iconview_edit.c</file>
     <file>images.c</file>
+    <file>image_view.c</file>
     <file>infobar.c</file>
     <file>links.c</file>
     <file>listbox.c</file>
@@ -229,6 +230,9 @@
     <file>textmask.c</file>
     <file>video_player.c</file>
   </gresource>
+  <gresource prefix="/imageview">
+    <file>image_view.ui</file>
+  </gresource>
   <gresource prefix="/textview">
     <file>floppybuddy.gif</file>
   </gresource>
diff --git a/demos/gtk-demo/image_view.c b/demos/gtk-demo/image_view.c
new file mode 100644
index 0000000000..0e1e3d2d3d
--- /dev/null
+++ b/demos/gtk-demo/image_view.c
@@ -0,0 +1,258 @@
+/* Image View
+ */
+#include <gtk/gtk.h>
+#include "paintable.h"
+
+GtkWidget *image_view;
+GtkWidget *uri_entry;
+
+
+void
+reset_view_button_clicked_cb ()
+{
+  gtk_image_view_set_scale (GTK_IMAGE_VIEW (image_view), 1.0);
+  gtk_image_view_set_angle (GTK_IMAGE_VIEW (image_view), 0.0);
+}
+
+void
+load_from_file_cb (GObject      *source_object,
+                   GAsyncResult *result,
+                   gpointer      user_data)
+{
+  GError *error = NULL;
+
+  gtk_image_view_load_from_file_finish (GTK_IMAGE_VIEW (image_view),
+                                        result,
+                                        &error);
+
+  if (error != NULL)
+    {
+      g_warning ("load_from_file_async error: %s", error->message);
+    }
+}
+
+void
+file_set_cb (GtkFileChooserButton *widget,
+             gpointer              user_data)
+{
+  char *filename = gtk_file_chooser_get_filename (GTK_FILE_CHOOSER (widget));
+  GFile *file = g_file_new_for_path (filename);
+
+  gtk_image_view_load_from_file_async (GTK_IMAGE_VIEW (image_view),
+                                       file,
+                                       NULL,
+                                       load_from_file_cb,
+                                       NULL);
+
+  g_free (filename);
+  g_object_unref (file);
+}
+
+static void
+image_loaded_cb (GObject      *source_object,
+                 GAsyncResult *result,
+                 gpointer      user_data)
+{
+  GtkImageView *image_view = GTK_IMAGE_VIEW (source_object);
+  GError *error = NULL;
+
+  gtk_image_view_load_from_file_finish (image_view,
+                                        result,
+                                        &error);
+
+  if (error)
+    {
+      g_message ("Error: %s", error->message);
+      return;
+    }
+}
+
+void
+load_button_cb ()
+{
+  const char *uri = gtk_editable_get_text (GTK_EDITABLE (uri_entry));
+  GFile *file = g_file_new_for_uri (uri);
+
+  g_message (__FUNCTION__);
+  gtk_image_view_load_from_file_async (GTK_IMAGE_VIEW (image_view),
+                                       file,
+                                       NULL,
+                                       image_loaded_cb,
+                                       NULL);
+  g_object_unref (file);
+}
+
+void
+angle_changed_cb (GtkRange *range,
+                  gpointer  user_data)
+{
+  double value = gtk_range_get_value (range);
+
+  gtk_image_view_set_angle (GTK_IMAGE_VIEW (image_view), value);
+}
+
+void
+scale_changed_cb (GtkRange *range,
+                  gpointer user_data)
+{
+  double value = gtk_range_get_value (range);
+
+  gtk_image_view_set_scale (GTK_IMAGE_VIEW (image_view), value);
+}
+
+void
+rotate_left_clicked_cb ()
+{
+  double current_angle = gtk_image_view_get_angle (GTK_IMAGE_VIEW (image_view));
+
+  gtk_image_view_set_angle (GTK_IMAGE_VIEW (image_view), current_angle - 90);
+}
+
+
+void
+rotate_right_clicked_cb ()
+{
+  double current_angle = gtk_image_view_get_angle (GTK_IMAGE_VIEW (image_view));
+
+  gtk_image_view_set_angle (GTK_IMAGE_VIEW (image_view), current_angle + 90);
+}
+
+void
+scrolled_switch_active_cb (GObject *source)
+{
+  GtkWidget *parent = gtk_widget_get_parent (image_view);
+
+  if (GTK_IS_SCROLLED_WINDOW (parent))
+    {
+      GtkWidget *grandparent = gtk_widget_get_parent (parent);
+      g_assert (grandparent != NULL);
+      g_object_ref (G_OBJECT (image_view));
+      gtk_container_remove (GTK_CONTAINER (parent), image_view);
+      gtk_container_remove (GTK_CONTAINER (grandparent), parent);
+      gtk_container_add (GTK_CONTAINER (grandparent), image_view);
+      gtk_widget_show (image_view);
+      g_object_unref (G_OBJECT (image_view));
+    }
+  else
+    {
+      GtkWidget *scroller = gtk_scrolled_window_new (NULL, NULL);
+      gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (scroller),
+                                      GTK_POLICY_ALWAYS,
+                                      GTK_POLICY_ALWAYS);
+      g_object_ref (image_view);
+      gtk_container_remove (GTK_CONTAINER (parent), image_view);
+      gtk_container_add (GTK_CONTAINER (scroller), image_view);
+      gtk_container_add (GTK_CONTAINER (parent), scroller);
+      gtk_widget_show (scroller);
+      g_object_unref (image_view);
+    }
+}
+
+gchar *
+angle_scale_format_value_cb (GtkScale *scale,
+                             double    value,
+                             gpointer  user_data)
+{
+  return g_strdup_printf ("%.2f°", value);
+}
+
+
+gchar *
+scale_scale_format_value_cb (GtkScale *scale,
+                             double    value,
+                             gpointer  user_data)
+{
+  return g_strdup_printf ("%.2f", value);
+}
+
+
+void
+load_pixbuf_button_clicked_cb ()
+{
+  GdkPixbuf *pixbuf;
+  GdkTexture *texture;
+
+  pixbuf = gdk_pixbuf_new_from_file ("/usr/share/backgrounds/gnome/AndICallItBoke.jpg", NULL);
+  texture = gdk_texture_new_for_pixbuf (pixbuf);
+  g_object_unref (pixbuf);
+
+  gtk_image_view_set_paintable (GTK_IMAGE_VIEW (image_view),
+                                GDK_PAINTABLE (texture));
+  g_object_unref (texture);
+}
+
+void
+load_hidpi_pixbuf_button_clicked_cb ()
+{
+  GdkPaintable *p;
+
+  p = gtk_nuclear_animation_new ();
+
+  gtk_image_view_set_paintable (GTK_IMAGE_VIEW (image_view), p);
+  g_object_unref (p);
+}
+
+void
+clear_button_clicked_cb ()
+{
+  gtk_image_view_set_paintable (GTK_IMAGE_VIEW (image_view), NULL);
+}
+
+GtkWidget *
+do_image_view (GtkWidget *do_widget)
+{
+  GtkWidget *window   = gtk_window_new (GTK_WINDOW_TOPLEVEL);
+  GtkBuilder *builder = gtk_builder_new_from_resource ("/imageview/image_view.ui");
+  GtkWidget *box      = GTK_WIDGET (gtk_builder_get_object (builder, "box"));
+  GtkWidget *snap_angle_switch = GTK_WIDGET (gtk_builder_get_object (builder, "snap_angle_switch"));
+  GtkWidget *fit_allocation_switch = GTK_WIDGET (gtk_builder_get_object (builder, "fit_allocation_switch"));
+  GtkWidget *rotate_gesture_switch = GTK_WIDGET (gtk_builder_get_object (builder, "rotate_gesture_switch"));
+  GtkWidget *zoom_gesture_switch = GTK_WIDGET (gtk_builder_get_object (builder, "zoom_gesture_switch"));
+  GtkWidget *transitions_switch = GTK_WIDGET (gtk_builder_get_object (builder, "transitions_switch"));
+
+  GtkAdjustment *scale_adjustment = GTK_ADJUSTMENT (gtk_builder_get_object (builder, "scale_adjustment"));
+  GtkAdjustment *angle_adjustment = GTK_ADJUSTMENT (gtk_builder_get_object (builder, "angle_adjustment"));
+         image_view   = GTK_WIDGET (gtk_builder_get_object (builder, "image_view"));
+          uri_entry   = GTK_WIDGET (gtk_builder_get_object (builder, "uri_entry"));
+
+
+  g_object_bind_property (scale_adjustment, "value", image_view, "scale",
+                          G_BINDING_BIDIRECTIONAL);
+
+  g_object_bind_property (angle_adjustment, "value", image_view, "angle",
+                          G_BINDING_SYNC_CREATE);
+  g_object_bind_property (image_view, "angle", angle_adjustment, "value",
+                          G_BINDING_SYNC_CREATE);
+
+
+
+  g_object_bind_property (image_view, "snap-angle", snap_angle_switch, "active",
+                          G_BINDING_BIDIRECTIONAL | G_BINDING_SYNC_CREATE);
+  g_object_bind_property (image_view, "fit-allocation", fit_allocation_switch, "active",
+                          G_BINDING_BIDIRECTIONAL | G_BINDING_SYNC_CREATE);
+
+  g_object_bind_property (image_view, "rotatable",
+                          rotate_gesture_switch, "active",
+                          G_BINDING_BIDIRECTIONAL | G_BINDING_SYNC_CREATE);
+
+  g_object_bind_property (image_view, "zoomable",
+                          zoom_gesture_switch, "active",
+                          G_BINDING_BIDIRECTIONAL | G_BINDING_SYNC_CREATE);
+
+  g_object_bind_property (image_view, "transitions-enabled",
+                          transitions_switch, "active",
+                          G_BINDING_BIDIRECTIONAL | G_BINDING_SYNC_CREATE);
+
+
+
+
+  gtk_container_add (GTK_CONTAINER (window), box);
+  gtk_builder_connect_signals (builder, NULL);
+
+  gtk_window_resize (GTK_WINDOW (window), 800, 600);
+  gtk_widget_show (window);
+
+  g_object_unref (builder);
+
+  return window;
+}
diff --git a/demos/gtk-demo/image_view.ui b/demos/gtk-demo/image_view.ui
new file mode 100644
index 0000000000..d397c8a4ff
--- /dev/null
+++ b/demos/gtk-demo/image_view.ui
@@ -0,0 +1,313 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<interface>
+  <object class="GtkAdjustment" id="scale_adjustment">
+    <property name="upper">5</property>
+    <property name="lower">0.05</property>
+    <property name="value">1.0</property>
+    <property name="step-increment">0.01</property>
+    <property name="page-increment">0.01</property>
+  </object>
+  <object class="GtkAdjustment" id="angle_adjustment">
+    <property name="upper">360</property>
+    <property name="step_increment">0.1</property>
+    <property name="page-increment">1</property>
+  </object>
+  <object class="GtkBox" id="box">
+    <child>
+      <object class="GtkGrid" id="grid">
+        <property name="row_spacing">6</property>
+        <property name="column_spacing">12</property>
+        <property name="margin">6</property>
+        <child>
+          <object class="GtkEntry" id="uri_entry">
+            <property name="placeholder_text">URI</property>
+          </object>
+        </child>
+        <child>
+          <object class="GtkButton" id="load_button">
+            <property name="label" translatable="yes">Load</property>
+            <signal name="clicked" handler="load_button_cb"/>
+            <layout>
+              <property name="left_attach">1</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkFileChooserButton">
+            <property name="valign">baseline</property>
+            <signal name="file-set" handler="file_set_cb"/>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">1</property>
+              <property name="column-span">2</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkButton">
+            <property name="label" translatable="yes">Load Pixbuf</property>
+            <signal name="clicked" handler="load_pixbuf_button_clicked_cb" object="image_view"/>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">2</property>
+              <property name="column-span">2</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkButton">
+            <property name="label" translatable="yes">Load HiDPI Pixbuf</property>
+            <signal name="clicked" handler="load_hidpi_pixbuf_button_clicked_cb" object="image_view"/>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">3</property>
+              <property name="column-span">2</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkButton">
+            <property name="label" translatable="yes">Clear</property>
+            <signal name="clicked" handler="clear_button_clicked_cb"/>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">4</property>
+              <property name="column-span">2</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="label" translatable="yes">Fit Allocation</property>
+            <property name="halign">start</property>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">6</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkSwitch" id="fit_allocation_switch">
+            <property name="halign">end</property>
+            <layout>
+              <property name="left_attach">1</property>
+              <property name="top_attach">6</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="label">In ScrolledWindow</property>
+            <property name="halign">start</property>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">7</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkSwitch" id="scrolled_switch">
+            <property name="halign">end</property>
+            <property name="active">1</property>
+            <signal name="notify::active" handler="scrolled_switch_active_cb"/>
+            <layout>
+              <property name="left_attach">1</property>
+              <property name="top_attach">7</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="label">Zoomable</property>
+            <property name="halign">start</property>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">8</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkSwitch" id="zoom_gesture_switch">
+            <property name="halign">end</property>
+            <property name="active">1</property>
+            <layout>
+              <property name="left_attach">1</property>
+              <property name="top_attach">8</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="label">Rotatable</property>
+            <property name="halign">start</property>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">9</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkSwitch" id="rotate_gesture_switch">
+            <property name="halign">end</property>
+            <property name="active">1</property>
+            <layout>
+              <property name="left_attach">1</property>
+              <property name="top_attach">9</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="label" translatable="yes">Snap Angle</property>
+            <property name="halign">start</property>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">10</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkSwitch" id="snap_angle_switch">
+            <property name="halign">end</property>
+            <layout>
+              <property name="left_attach">1</property>
+              <property name="top_attach">10</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="label" translatable="yes">Transitions</property>
+            <property name="halign">start</property>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">11</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkSwitch" id="transitions_switch">
+            <property name="halign">end</property>
+            <layout>
+              <property name="left_attach">1</property>
+              <property name="top_attach">11</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="label" translatable="yes">Angle</property>
+            <property name="margin_top">12</property>
+            <property name="halign">start</property>
+            <attributes>
+              <attribute name="weight" value="bold"></attribute>
+            </attributes>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">12</property>
+              <property name="column-span">2</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkScale" id="angle_spin_button">
+            <property name="draw-value">0</property>
+            <property name="digits">2</property>
+            <property name="draw-value">0</property>
+            <property name="adjustment">angle_adjustment</property>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">13</property>
+              <property name="column-span">2</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="label" translatable="yes">Scale</property>
+            <property name="halign">start</property>
+            <property name="xalign">0.0</property>
+            <attributes>
+              <attribute name="weight" value="bold"></attribute>
+            </attributes>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">14</property>
+              <property name="column-span">2</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkScale" id="scale_spin_button">
+            <property name="draw-value">0</property>
+            <property name="digits">2</property>
+            <property name="adjustment">scale_adjustment</property>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">15</property>
+              <property name="column-span">2</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkBox">
+            <property name="halign">center</property>
+            <style>
+              <class name="linked"/>
+            </style>
+            <child>
+              <object class="GtkButton">
+                <signal name="clicked" handler="rotate_left_clicked_cb"/>
+                <child>
+                  <object class="GtkImage">
+                    <property name="icon-name">object-rotate-left-symbolic</property>
+                  </object>
+                </child>
+              </object>
+            </child>
+            <child>
+              <object class="GtkButton">
+                <signal name="clicked" handler="rotate_right_clicked_cb"/>
+                <child>
+                  <object class="GtkImage">
+                    <property name="icon-name">object-rotate-right-symbolic</property>
+                  </object>
+                </child>
+              </object>
+            </child>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">16</property>
+              <property name="column-span">2</property>
+            </layout>
+          </object>
+        </child>
+        <child>
+          <object class="GtkButton" id="reset_button">
+            <property name="label" translatable="true">Reset View</property>
+            <property name="valign">end</property>
+            <property name="vexpand">1</property>
+            <signal name="clicked" handler="reset_view_button_clicked_cb"/>
+            <layout>
+              <property name="left_attach">0</property>
+              <property name="top_attach">17</property>
+              <property name="column-span">2</property>
+            </layout>
+          </object>
+        </child>
+      </object>
+    </child>
+    <child>
+      <object class="GtkScrolledWindow">
+        <child>
+          <object class="GtkImageView" id="image_view">
+            <property name="hexpand">1</property>
+            <property name="vexpand">1</property>
+            <property name="width_request">400</property>
+            <property name="height_request">400</property>
+          </object>
+        </child>
+      </object>
+    </child>
+  </object>
+</interface>
diff --git a/demos/gtk-demo/meson.build b/demos/gtk-demo/meson.build
index c021f9f60a..ad66c0b181 100644
--- a/demos/gtk-demo/meson.build
+++ b/demos/gtk-demo/meson.build
@@ -38,6 +38,7 @@ demos = files([
   'iconview.c',
   'iconview_edit.c',
   'images.c',
+  'image_view.c',
   'infobar.c',
   'links.c',
   'listbox.c',
diff --git a/docs/reference/gtk/gtk4-docs.xml b/docs/reference/gtk/gtk4-docs.xml
index 1835c7b1be..2edc2d42dc 100644
--- a/docs/reference/gtk/gtk4-docs.xml
+++ b/docs/reference/gtk/gtk4-docs.xml
@@ -120,6 +120,7 @@
       <xi:include href="xml/gtklabel.xml" />
       <xi:include href="xml/gtkimage.xml" />
       <xi:include href="xml/gtkpicture.xml" />
+      <xi:include href="xml/gtkimageview.xml" />
       <xi:include href="xml/gtkspinner.xml" />
       <xi:include href="xml/gtkinfobar.xml" />
       <xi:include href="xml/gtkprogressbar.xml" />
diff --git a/docs/reference/gtk/gtk4-sections.txt b/docs/reference/gtk/gtk4-sections.txt
index 6a246c8e9a..5beccf9aea 100644
--- a/docs/reference/gtk/gtk4-sections.txt
+++ b/docs/reference/gtk/gtk4-sections.txt
@@ -1638,6 +1638,45 @@ GtkImageIconNameData
 GtkImageGIconData
 </SECTION>
 
+<SECTION>
+<FILE>gtkimageview</FILE>
+<TITLE>GtkImageView</TITLE>
+GtkImageView
+gtk_image_view_new
+gtk_image_view_set_pixbuf
+gtk_image_view_set_surface
+gtk_image_view_set_animation
+gtk_image_view_load_from_file_async
+gtk_image_view_load_from_file_finish
+gtk_image_view_load_from_stream_async
+gtk_image_view_load_from_stream_finish
+gtk_image_view_set_scale
+gtk_image_view_get_scale
+gtk_image_view_set_angle
+gtk_image_view_get_angle
+gtk_image_view_set_snap_angle
+gtk_image_view_get_snap_angle
+gtk_image_view_set_fit_allocation
+gtk_image_view_get_fit_allocation
+gtk_image_view_set_rotatable
+gtk_image_view_get_rotatable
+gtk_image_view_set_zoomable
+gtk_image_view_get_zoomable
+gtk_image_view_get_scale_set
+gtk_image_view_set_transitions_enabled
+gtk_image_view_get_transitions_enabled
+<SUBSECTION Standard>
+GTK_IMAGE_VIEW
+GTK_IS_IMAGE_VIEW
+GTK_TYPE_IMAGE_VIEW
+GTK_IMAGE__VIEW_CLASS
+GTK_IS_IMAGE_VIEW_CLASS
+GTK_IMAGE_VIEW_GET_CLASS
+<SUBSECTION Private>
+GtkImageViewPrivate
+gtk_image_view_get_type
+</SECTION>
+
 <SECTION>
 <FILE>gtkimcontext</FILE>
 <TITLE>GtkIMContext</TITLE>
diff --git a/docs/reference/gtk/gtk4.types.in b/docs/reference/gtk/gtk4.types.in
index 23e796d637..d407e8f900 100644
--- a/docs/reference/gtk/gtk4.types.in
+++ b/docs/reference/gtk/gtk4.types.in
@@ -99,6 +99,7 @@ gtk_header_bar_get_type
 gtk_icon_theme_get_type
 gtk_icon_view_get_type
 gtk_image_get_type
+gtk_image_view_get_type
 gtk_im_context_get_type
 gtk_im_context_simple_get_type
 gtk_im_multicontext_get_type
diff --git a/docs/reference/gtk/visual_index.xml b/docs/reference/gtk/visual_index.xml
index b75e192c54..522c8736c7 100644
--- a/docs/reference/gtk/visual_index.xml
+++ b/docs/reference/gtk/visual_index.xml
@@ -33,6 +33,9 @@
     <link linkend="GtkImage">
       <inlinegraphic fileref="image.png" format="PNG"></inlinegraphic>
     </link>
+    <link linkend="GtkImageView">
+      <inlinegraphic fileref="image.png" format="PNG"></inlinegraphic>
+    </link>
     <link linkend="GtkSeparator">
       <inlinegraphic fileref="separator.png" format="PNG"></inlinegraphic>
     </link>
diff --git a/gdk/gdkpaintable.h b/gdk/gdkpaintable.h
index 7686286c87..3ca99b9f3d 100644
--- a/gdk/gdkpaintable.h
+++ b/gdk/gdkpaintable.h
@@ -93,7 +93,7 @@ struct _GdkPaintableInterface
                                                          double                  height);
   /* get the current contents in an immutable form (optional) */
   GdkPaintable *        (* get_current_image)           (GdkPaintable           *paintable);
-   
+
   /* get flags for potential optimizations (optional) */
   GdkPaintableFlags     (* get_flags)                   (GdkPaintable           *paintable);
   /* preferred width of paintable or 0 if it has no width (optional) */
diff --git a/gtk/gtk.h b/gtk/gtk.h
index 4ce7e58098..031f66a4b4 100644
--- a/gtk/gtk.h
+++ b/gtk/gtk.h
@@ -138,6 +138,7 @@
 #include <gtk/gtkicontheme.h>
 #include <gtk/gtkiconview.h>
 #include <gtk/gtkimage.h>
+#include <gtk/gtkimageview.h>
 #include <gtk/gtkimcontext.h>
 #include <gtk/gtkimcontextsimple.h>
 #include <gtk/gtkimmulticontext.h>
diff --git a/gtk/gtkimageview.c b/gtk/gtkimageview.c
new file mode 100644
index 0000000000..271f497d11
--- /dev/null
+++ b/gtk/gtkimageview.c
@@ -0,0 +1,2179 @@
+/*  Copyright 2018 Timm Bäder
+ *
+ * GTK+ is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * GLib is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with GTK+; see the file COPYING.  If not,
+ * see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * SECTION:gtkimageview
+ * @Short_description: A widget for displaying content images to users
+ * @Title: GtkImageView
+ *
+ * #GtkImageView is a widget intended to be used to display "content images"
+ * to users. What we refer to as "content images" in the documentation could
+ * be characterized as "images the user is deeply interested in". You should
+ * use #GtkImageView whenever you want to actually present an image instead
+ * of just using an icon.
+ */
+
+#include "config.h"
+#include "gtkimageview.h"
+#include "gtkintl.h"
+#include "gtkprivate.h"
+#include "gtkgesturerotate.h"
+#include "gtkgesturezoom.h"
+#include "gtkscrollable.h"
+#include "gtkadjustment.h"
+#include "gtkprogresstrackerprivate.h"
+#include "gtkeventcontrollerscroll.h"
+#include "gtkeventcontrollermotion.h"
+#include "gtksnapshot.h"
+#include "gtkwidgetprivate.h"
+#include <math.h>
+
+#define DEG_TO_RAD(x) (((x) / 360.0) * (2 * M_PI))
+#define RAD_TO_DEG(x) (((x) / (2.0 * M_PI) * 360.0))
+
+#define TRANSITION_DURATION (150.0 * 1000.0)
+#define ANGLE_TRANSITION_MIN_DELTA (1.0)
+#define SCALE_TRANSITION_MIN_DELTA (0.01)
+
+
+typedef struct
+{
+  double hupper;
+  double vupper;
+  double hvalue;
+  double vvalue;
+  double angle;
+  double scale;
+} ViewState;
+
+typedef struct
+{
+  GdkPaintable *paintable;
+
+  double   scale;
+  double   angle;
+
+  guint fit_allocation      : 1;
+  guint scale_set           : 1;
+  guint snap_angle          : 1;
+  guint rotatable           : 1;
+  guint zoomable            : 1;
+  guint in_rotate           : 1;
+  guint in_zoom             : 1;
+  guint transitions_enabled : 1;
+  guint in_angle_transition : 1;
+  guint in_scale_transition : 1;
+
+  GtkProgressTracker scale_tracker;
+  GtkProgressTracker angle_tracker;
+
+  GtkGesture *rotate_gesture;
+  double      gesture_start_angle;
+  double      visible_angle;
+
+  GtkGesture *zoom_gesture;
+  GtkEventController *zoom_controller;
+  double      gesture_start_scale;
+  double      visible_scale;
+
+  GtkEventController *motion_controller;
+
+  /* Current anchor point, or -1/-1.
+   * In widget coordinates. */
+  double      anchor_x;
+  double      anchor_y;
+
+  /* GtkScrollable stuff */
+  GtkAdjustment       *hadjustment;
+  GtkAdjustment       *vadjustment;
+  GtkScrollablePolicy  hscroll_policy : 1;
+  GtkScrollablePolicy  vscroll_policy : 1;
+
+  /* Transitions */
+  double transition_start_angle;
+  guint  angle_transition_id;
+
+  double transition_start_scale;
+  guint  scale_transition_id;
+
+  /* Event state */
+  double mouse_x;
+  double mouse_y;
+
+} GtkImageViewPrivate;
+
+enum
+{
+  PROP_SCALE = 1,
+  PROP_SCALE_SET,
+  PROP_ANGLE,
+  PROP_ROTATABLE,
+  PROP_ZOOMABLE,
+  PROP_SNAP_ANGLE,
+  PROP_FIT_ALLOCATION,
+  PROP_TRANSITIONS_ENABLED,
+
+  LAST_WIDGET_PROPERTY,
+  PROP_HADJUSTMENT,
+  PROP_VADJUSTMENT,
+  PROP_HSCROLL_POLICY,
+  PROP_VSCROLL_POLICY,
+
+  LAST_PROPERTY
+};
+
+static GParamSpec *widget_props[LAST_WIDGET_PROPERTY] = { NULL, };
+
+
+G_DEFINE_TYPE_WITH_CODE (GtkImageView, gtk_image_view, GTK_TYPE_WIDGET,
+                         G_ADD_PRIVATE (GtkImageView)
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_SCROLLABLE, NULL))
+
+static void adjustment_value_changed_cb (GtkAdjustment *adjustment,
+                                         gpointer       user_data);
+
+static void gtk_image_view_update_adjustments (GtkImageView *self);
+
+static void gtk_image_view_compute_bounding_box (GtkImageView *self,
+                                                 double       *bb_width_out,
+                                                 double       *bb_height_out,
+                                                 double       *paintable_width_out,
+                                                 double       *paintable_height_out);
+static void gtk_image_view_ensure_gestures (GtkImageView *self);
+
+static void gtk_image_view_fix_anchor2 (GtkImageView    *self,
+                                        double           anchor_x,
+                                        double           anchor_y,
+                                        const ViewState *old_state);
+
+
+static inline void
+update_adjustment (GtkAdjustment *adjustment,
+                   double         upper,
+                   double         page_size)
+{
+  double value = gtk_adjustment_get_value (adjustment);
+
+  if (value > upper - page_size)
+    value = upper - page_size;
+
+  gtk_adjustment_configure (adjustment,
+                            value,
+                            gtk_adjustment_get_lower (adjustment),
+                            upper,
+                            gtk_adjustment_get_step_increment (adjustment),
+                            gtk_adjustment_get_page_increment (adjustment),
+                            page_size);
+}
+
+static inline void
+gtk_image_view_invalidate (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->fit_allocation)
+    gtk_widget_queue_draw (GTK_WIDGET (self));
+  else
+    gtk_widget_queue_resize (GTK_WIDGET (self));
+}
+
+static inline double
+gtk_image_view_get_real_scale (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->in_zoom || priv->in_scale_transition)
+    return priv->visible_scale;
+  else
+    return priv->scale;
+}
+
+static inline double
+gtk_image_view_get_real_angle (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  /*return 90;*/
+
+  if (priv->in_rotate || priv->in_angle_transition)
+    return priv->visible_angle;
+  else
+    return priv->angle;
+}
+
+static inline double
+gtk_image_view_clamp_angle (double angle)
+{
+  double new_angle = angle;
+
+  if (angle > 360.0)
+    new_angle -= (int)(angle / 360.0) * 360;
+  else if (angle < 0.0)
+    new_angle += 360 - ((int)(angle  /360) * 360.0);
+
+  g_assert (new_angle >= 0.0);
+  g_assert (new_angle <= 360.0);
+
+  return new_angle;
+}
+
+static inline int
+gtk_image_view_get_snapped_angle (double angle)
+{
+  return (int) ((angle + 45.0) / 90.0) * 90;
+}
+
+static void
+gtk_image_view_get_current_state (GtkImageView *self,
+                                  ViewState    *state)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->hadjustment != NULL && priv->vadjustment != NULL)
+    {
+      state->hvalue = gtk_adjustment_get_value (priv->hadjustment);
+      state->vvalue = gtk_adjustment_get_value (priv->vadjustment);
+      state->hupper = gtk_adjustment_get_upper (priv->hadjustment);
+      state->vupper = gtk_adjustment_get_upper (priv->vadjustment);
+    }
+  state->angle = gtk_image_view_get_real_angle (self);
+  state->scale = gtk_image_view_get_real_scale (self);
+}
+
+static gboolean
+gtk_image_view_transitions_enabled (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  gboolean animations_enabled;
+
+  g_object_get (gtk_widget_get_settings (GTK_WIDGET (self)),
+                "gtk-enable-animations", &animations_enabled,
+                NULL);
+
+  return priv->transitions_enabled &&
+         animations_enabled &&
+         priv->paintable &&
+         gtk_widget_get_mapped (GTK_WIDGET (self));
+}
+
+static GskTransform *
+gtk_image_view_get_transform (GtkImageView      *self,
+                              const ViewState   *state)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  int widget_width;
+  int widget_height;
+  double draw_x = 0;
+  double draw_y = 0;
+  double paintable_width;
+  double paintable_height;
+  double bb_width, bb_height;
+  GskTransform *t;
+
+  if (!priv->paintable)
+    return NULL;
+
+  gtk_image_view_compute_bounding_box (self,
+                                       &bb_width,
+                                       &bb_height,
+                                       &paintable_width,
+                                       &paintable_height);
+
+  if (paintable_width <= 0 || paintable_height <= 0)
+    return NULL;
+
+  widget_width = gtk_widget_get_width (GTK_WIDGET (self));
+  widget_height = gtk_widget_get_height (GTK_WIDGET (self));
+
+  if (priv->fit_allocation)
+    {
+      draw_x = (widget_width  - bb_width)  / 2.0;
+      draw_y = (widget_height - bb_height) / 2.0;
+    }
+  else
+    {
+      /* If the image we draw is smaller than the widget size, we
+       * center it anyway */
+      if (bb_width <= widget_width)
+        {
+          draw_x = (widget_width - paintable_width)  / 2.0;
+        }
+      else if (priv->hadjustment)
+        {
+          draw_x = -gtk_adjustment_get_value (priv->hadjustment);
+        }
+
+      if (bb_height <= widget_height)
+        {
+          draw_y = (widget_height - paintable_height)  / 2.0;
+        }
+      else if (priv->vadjustment)
+        {
+          draw_y = -gtk_adjustment_get_value (priv->vadjustment);
+        }
+    }
+
+  t = NULL;
+
+  t = gsk_transform_translate (t, &(graphene_point_t) { draw_x, draw_y });
+  t = gsk_transform_translate (t, &(graphene_point_t) { bb_width / 2.0f, bb_height / 2.0f});
+  t = gsk_transform_rotate (t, gtk_image_view_get_real_angle (self));
+  t = gsk_transform_translate (t, &(graphene_point_t) { - paintable_width  / 2.0f, - paintable_height / 
2.0f});
+
+
+  return t;
+}
+
+static void
+paintable_contents_changed_cb (GdkPaintable *paintable,
+                               gpointer      user_data)
+{
+  GtkImageView *self = user_data;
+
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+static gboolean
+scale_frameclock_cb (GtkWidget     *widget,
+                     GdkFrameClock *frame_clock,
+                     gpointer       user_data)
+{
+  GtkImageView *self = GTK_IMAGE_VIEW (widget);
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  ViewState state;
+  double t;
+  double new_scale;
+
+  gtk_progress_tracker_advance_frame (&priv->scale_tracker, gdk_frame_clock_get_frame_time (frame_clock));
+  t = gtk_progress_tracker_get_ease_out_cubic (&priv->scale_tracker, FALSE);
+
+  new_scale = (priv->scale - priv->transition_start_scale) * t;
+
+  gtk_image_view_get_current_state (self, &state);
+
+  priv->visible_scale = priv->transition_start_scale + new_scale;
+
+  if (t >= 1.0)
+    priv->in_scale_transition = FALSE;
+
+  if (priv->hadjustment && priv->vadjustment)
+    {
+      gtk_image_view_update_adjustments (self);
+
+      gtk_image_view_fix_anchor2 (self,
+                                 gtk_widget_get_width (widget)  / 2,
+                                 gtk_widget_get_height (widget) / 2,
+                                 &state);
+    }
+
+  gtk_image_view_invalidate (self);
+
+  if (gtk_progress_tracker_get_state (&priv->scale_tracker) == GTK_PROGRESS_STATE_AFTER)
+    {
+      priv->scale_transition_id = 0;
+      return G_SOURCE_REMOVE;
+    }
+
+  return G_SOURCE_CONTINUE;
+}
+
+static void
+gtk_image_view_animate_to_scale (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->scale_transition_id != 0)
+    gtk_widget_remove_tick_callback (GTK_WIDGET (self), priv->scale_transition_id);
+
+  /* Target scale is priv->scale */
+  priv->in_scale_transition = TRUE;
+  priv->visible_scale = priv->scale;
+  priv->transition_start_scale = priv->scale;
+
+  gtk_progress_tracker_start (&priv->scale_tracker, TRANSITION_DURATION, 0, 1.0);
+  priv->scale_transition_id = gtk_widget_add_tick_callback (GTK_WIDGET (self),
+                                                            scale_frameclock_cb,
+                                                            NULL, NULL);
+}
+
+static gboolean
+angle_frameclock_cb (GtkWidget     *widget,
+                     GdkFrameClock *frame_clock,
+                     gpointer       user_data)
+{
+  GtkImageView *self = GTK_IMAGE_VIEW (widget);
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  const int direction = GPOINTER_TO_INT (user_data);
+  double new_angle;
+  double t;
+  ViewState state;
+  double target_angle = priv->angle;
+
+  if (direction == 1 && target_angle < priv->transition_start_angle)
+    target_angle += 360.0;
+  else if (direction == 0 && target_angle > priv->transition_start_angle)
+    target_angle -= 360.0;
+
+  gtk_progress_tracker_advance_frame (&priv->angle_tracker, gdk_frame_clock_get_frame_time (frame_clock));
+  t = gtk_progress_tracker_get_ease_out_cubic (&priv->angle_tracker, FALSE);
+  new_angle = (target_angle - priv->transition_start_angle) * t;
+
+  gtk_image_view_get_current_state (self, &state);
+
+  priv->visible_angle = priv->transition_start_angle + new_angle;
+
+  if (t >= 1.0)
+    priv->in_angle_transition = FALSE;
+
+  if (priv->hadjustment && priv->vadjustment)
+    {
+      gtk_image_view_update_adjustments (self);
+
+      gtk_image_view_fix_anchor2 (self,
+                                 gtk_widget_get_width (widget)  / 2,
+                                 gtk_widget_get_height (widget) / 2,
+                                 &state);
+
+    }
+
+  gtk_image_view_invalidate (self);
+
+  if (gtk_progress_tracker_get_state (&priv->angle_tracker) == GTK_PROGRESS_STATE_AFTER)
+    {
+      priv->angle_transition_id = 0;
+      return G_SOURCE_REMOVE;
+    }
+
+  return G_SOURCE_CONTINUE;
+}
+
+static void
+gtk_image_view_animate_to_angle (GtkImageView *self,
+                                 int           direction)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->angle_transition_id != 0)
+    {
+      gtk_widget_remove_tick_callback (GTK_WIDGET (self), priv->angle_transition_id);
+      priv->angle_transition_id = 0;
+    }
+
+  /* Target angle is priv->angle */
+  priv->in_angle_transition = TRUE;
+  priv->visible_angle = priv->angle;
+  priv->transition_start_angle = priv->angle;
+
+  gtk_progress_tracker_start (&priv->angle_tracker, TRANSITION_DURATION, 0, 1.0);
+  priv->angle_transition_id = gtk_widget_add_tick_callback (GTK_WIDGET (self),
+                                                            angle_frameclock_cb,
+                                                            GINT_TO_POINTER (direction),
+                                                            NULL);
+}
+
+static void
+gtk_image_view_do_snapping (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  double new_angle = gtk_image_view_get_snapped_angle (priv->angle);
+
+  g_assert (priv->snap_angle);
+
+  if (gtk_image_view_transitions_enabled (self))
+    gtk_image_view_animate_to_angle (self, new_angle > priv->angle);
+
+  priv->angle = new_angle;
+
+  /* Don't notify! */
+}
+
+/*
+ * The anchor here is given in widget coordinates.
+ *
+ * The task now is to...
+ *   1) Calculate the position of the anchor on the untransformed image.
+ *      That means we have to remove both scaling and rotation from the image
+ *      and calculate where the anchor point would be now.
+ *      angle and scale for this are saved in @old_state.
+ *   2) Now transform the anchor point by the new state, i.e. apply both
+ *      scale and angle to it.
+ */
+static void
+gtk_image_view_fix_anchor2 (GtkImageView    *self,
+                            double           anchor_x,
+                            double           anchor_y,
+                            const ViewState *old_state)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  ViewState new_state;
+  GskTransform *transform;
+
+  g_message (__FUNCTION__);
+
+  g_assert (!priv->fit_allocation);
+  g_assert (old_state->hupper >= 0);
+  g_assert (old_state->vupper >= 0);
+  g_assert (priv->hadjustment);
+  g_assert (priv->vadjustment);
+  g_assert (anchor_x >= 0);
+  g_assert (anchor_y >= 0);
+  g_assert (anchor_x < gtk_widget_get_width (GTK_WIDGET (self)));
+  g_assert (anchor_y < gtk_widget_get_height (GTK_WIDGET (self)));
+
+  priv->anchor_x = anchor_x;
+  priv->anchor_y = anchor_y;
+
+  gtk_image_view_get_current_state (self, &new_state);
+
+}
+
+/*
+ * In here, we need to differenciate between the actual bounding box size,
+ * i.e. the box around the scaled, rotated paintable -- and the size
+ * we need to pass to gdk_paintable_snapshot to achieve the correct rendering.
+ *
+ * The size we assign to @paintable_width_out and @paintable_height_out is
+ * the one we really need to pass directly to gdk_paintable_snapshot. No
+ * scaling will have to be applied before.
+ * This especially means that we don't explicitly scale the paintable at all,
+ * we just increase the size we pass to gdk_paintable_snapshot() and let the
+ * paintable handle it. This way, e.g. SVGs will scale.
+ */
+static void
+gtk_image_view_compute_bounding_box (GtkImageView *self,
+                                     double       *bb_width_out,
+                                     double       *bb_height_out,
+                                     double       *paintable_width_out,
+                                     double       *paintable_height_out)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  int widget_width, widget_height;
+  double paintable_width;
+  double paintable_height;
+  double bb_width;
+  double bb_height;
+  double scale;
+  double angle;
+
+  g_assert (bb_width_out != NULL);
+  g_assert (bb_height_out != NULL);
+
+  if (!priv->paintable)
+    {
+      *bb_width_out  = 0;
+      *bb_height_out = 0;
+
+      if (paintable_width_out)
+        *paintable_width_out = 0;
+
+      if (paintable_height_out)
+        *paintable_height_out = 0;
+      return;
+    }
+
+  widget_width = gtk_widget_get_width (GTK_WIDGET (self));
+  widget_height = gtk_widget_get_height (GTK_WIDGET (self));
+  angle = gtk_image_view_get_real_angle (self);
+
+  /* XXX Passing the widget size as default size is probably wrong if
+   *     priv->fit_allocation is FALSE? */
+  gdk_paintable_compute_concrete_size (priv->paintable,
+                                       0, 0,
+                                       widget_width,
+                                       widget_height,
+                                       &paintable_width,
+                                       &paintable_height);
+
+  /* Calculate the bounding box of the rotated image */
+  {
+    graphene_rect_t bounds;
+    graphene_matrix_t transform;
+
+    graphene_rect_init (&bounds, 0, 0, paintable_width, paintable_height);
+    graphene_matrix_init_identity (&transform);
+    graphene_matrix_rotate (&transform, angle, graphene_vec3_z_axis ());
+
+    graphene_matrix_transform_bounds (&transform, &bounds, &bounds);
+
+    bb_width = bounds.size.width;
+    bb_height = bounds.size.height;
+  }
+
+  if (priv->fit_allocation)
+    {
+      const double scale_x = (double)widget_width / (double)bb_width;
+      const double scale_y = (double)widget_height / (double)bb_height;
+
+      scale = MIN (MIN (scale_x, scale_y), 1.0);
+    }
+  else
+    {
+      scale = gtk_image_view_get_real_scale (self);
+    }
+
+  /* TODO: Doing this here seems *very* wrong. */
+  if (priv->fit_allocation)
+    {
+      g_assert (!priv->scale_set);
+      if (priv->scale != scale)
+        {
+          priv->scale = scale;
+          g_object_notify_by_pspec (G_OBJECT (self),
+                                    widget_props[PROP_SCALE]);
+        }
+    }
+
+  *bb_width_out  = bb_width  * scale;
+  *bb_height_out = bb_height * scale;
+
+  if (paintable_width_out)
+    *paintable_width_out = paintable_width * scale;
+
+  if (paintable_height_out)
+    *paintable_height_out = paintable_height * scale;
+}
+
+static void
+gtk_image_view_update_adjustments (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  const int widget_width  = gtk_widget_get_width  (GTK_WIDGET (self));
+  const int widget_height = gtk_widget_get_height (GTK_WIDGET (self));
+  double bb_width, bb_height;
+
+  if (!priv->hadjustment && !priv->vadjustment)
+    return;
+
+  if (!priv->paintable)
+    {
+      if (priv->hadjustment)
+        gtk_adjustment_configure (priv->hadjustment, 0, 0, 1, 0, 0, 1);
+
+      if (priv->vadjustment)
+        gtk_adjustment_configure (priv->vadjustment, 0, 0, 1, 0, 0, 1);
+
+      return;
+    }
+
+  if (priv->fit_allocation)
+    {
+      bb_width = widget_width;
+      bb_height = widget_height;
+    }
+  else
+    {
+      gtk_image_view_compute_bounding_box (self,
+                                           &bb_width,
+                                           &bb_height,
+                                           NULL,
+                                           NULL);
+    }
+
+  /* compute_bounding_box makes sure that the bounding box is never bigger than
+   * the widget allocation if fit-allocation is set.
+   * We cast width/height to int anyway to avoid tiny differences in size */
+  if (priv->hadjustment)
+    {
+      update_adjustment (priv->hadjustment,
+                         MAX ((int)bb_width, widget_width),
+                         widget_width);
+    }
+
+  if (priv->vadjustment)
+    {
+      update_adjustment (priv->vadjustment,
+                         MAX ((int)bb_height, widget_height),
+                         widget_height);
+    }
+}
+
+static void
+gtk_image_view_set_scale_internal (GtkImageView *self,
+                                   double        scale)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  scale = MAX (0, scale);
+
+  priv->scale = scale;
+  g_object_notify_by_pspec (G_OBJECT (self),
+                            widget_props[PROP_SCALE]);
+
+  if (priv->scale_set)
+    {
+      priv->scale_set = FALSE;
+      g_object_notify_by_pspec (G_OBJECT (self),
+                                widget_props[PROP_SCALE_SET]);
+    }
+
+  if (priv->fit_allocation)
+    {
+      priv->fit_allocation = FALSE;
+      g_object_notify_by_pspec (G_OBJECT (self),
+                                widget_props[PROP_FIT_ALLOCATION]);
+    }
+
+  gtk_image_view_update_adjustments (self);
+
+  gtk_image_view_invalidate (self);
+}
+
+static void
+gesture_zoom_begin_cb (GtkGesture       *gesture,
+                       GdkEventSequence *sequence,
+                       gpointer          user_data)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (user_data);
+
+  if (!priv->zoomable ||
+      !priv->paintable)
+    {
+      gtk_gesture_set_state (gesture, GTK_EVENT_SEQUENCE_DENIED);
+      return;
+    }
+
+  if (priv->anchor_x == -1 && priv->anchor_y == -1)
+    {
+      gtk_gesture_get_bounding_box_center (gesture,
+                                           &priv->anchor_x,
+                                           &priv->anchor_y);
+    }
+}
+
+static void
+gesture_zoom_end_cb (GtkGesture       *gesture,
+                     GdkEventSequence *sequence,
+                     gpointer          self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  gtk_image_view_set_scale_internal (self, priv->visible_scale);
+
+  priv->in_zoom = FALSE;
+  priv->anchor_x = -1;
+  priv->anchor_y = -1;
+}
+
+static void
+gesture_zoom_cancel_cb (GtkGesture       *gesture,
+                        GdkEventSequence *sequence,
+                        gpointer          user_data)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (user_data);
+
+  if (priv->in_zoom)
+    gtk_image_view_set_scale (user_data, priv->gesture_start_scale);
+
+  priv->in_zoom = FALSE;
+  priv->anchor_x = -1;
+  priv->anchor_y = -1;
+}
+
+static void
+gesture_zoom_changed_cb (GtkGestureZoom *gesture,
+                          double          delta,
+                          GtkWidget      *widget)
+{
+  GtkImageView *self = GTK_IMAGE_VIEW (widget);
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  ViewState state;
+  double new_scale;
+
+  if (!priv->in_zoom)
+    {
+      priv->in_zoom = TRUE;
+      priv->gesture_start_scale = priv->scale;
+    }
+
+  if (priv->fit_allocation)
+    {
+      priv->fit_allocation = FALSE;
+      g_object_notify_by_pspec (G_OBJECT (widget),
+                                widget_props[PROP_FIT_ALLOCATION]);
+    }
+
+  new_scale = priv->gesture_start_scale * delta;
+  gtk_image_view_get_current_state (self, &state);
+
+  priv->visible_scale = new_scale;
+
+  gtk_image_view_update_adjustments (self);
+
+  if (priv->hadjustment != NULL && priv->vadjustment != NULL)
+    {
+      gtk_image_view_fix_anchor2 (self,
+                                  priv->anchor_x,
+                                  priv->anchor_y,
+                                  &state);
+    }
+
+  gtk_image_view_invalidate (self);
+}
+
+static void
+gesture_rotate_begin_cb (GtkGesture       *gesture,
+                         GdkEventSequence *sequence,
+                         gpointer          user_data)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (user_data);
+
+  if (!priv->rotatable ||
+      !priv->paintable)
+    {
+      gtk_gesture_set_state (gesture, GTK_EVENT_SEQUENCE_DENIED);
+      return;
+    }
+
+  if (priv->anchor_x == -1 && priv->anchor_y == -1)
+    {
+      gtk_gesture_get_bounding_box_center (gesture,
+                                           &priv->anchor_x,
+                                           &priv->anchor_y);
+    }
+}
+
+static void
+gesture_rotate_end_cb (GtkGesture       *gesture,
+                       GdkEventSequence *sequence,
+                       gpointer          self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  priv->angle = gtk_image_view_clamp_angle (priv->visible_angle);
+
+  if (priv->snap_angle)
+    {
+      /* Will update priv->angle */
+      gtk_image_view_do_snapping (self);
+    }
+  g_object_notify_by_pspec (self,
+                            widget_props[PROP_ANGLE]);
+
+  priv->in_rotate = FALSE;
+  priv->anchor_x = -1;
+  priv->anchor_y = -1;
+}
+
+static void
+gesture_rotate_cancel_cb (GtkGesture       *gesture,
+                          GdkEventSequence *sequence,
+                          gpointer          self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  gtk_image_view_update_adjustments (self);
+
+  priv->in_rotate = FALSE;
+  priv->anchor_x = -1;
+  priv->anchor_y = -1;
+}
+
+static void
+gesture_rotate_changed_cb (GtkGestureRotate *gesture,
+                          double            angle,
+                          double            delta,
+                          GtkWidget        *widget)
+{
+  GtkImageView *self = GTK_IMAGE_VIEW (widget);
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  ViewState old_state;
+  double new_angle;
+
+  if (!priv->in_rotate)
+    {
+      priv->in_rotate = TRUE;
+      priv->gesture_start_angle = priv->angle;
+    }
+
+  new_angle = priv->gesture_start_angle + RAD_TO_DEG (delta);
+  gtk_image_view_get_current_state (self, &old_state);
+
+  priv->visible_angle = new_angle;
+  gtk_image_view_update_adjustments (self);
+
+  if (priv->hadjustment && priv->vadjustment && !priv->fit_allocation)
+    gtk_image_view_fix_anchor2 (self,
+                               priv->anchor_x,
+                               priv->anchor_y,
+                               &old_state);
+
+  gtk_image_view_invalidate (self);
+}
+
+static void
+scroll_controller_scroll_cb (GtkEventControllerScroll *controller,
+                             double                    dx,
+                             double                    dy,
+                             gpointer                  user_data)
+{
+  GtkImageView *self = user_data;
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  double new_scale;
+  ViewState state;
+
+  new_scale = MAX (0, priv->scale - (0.02 * dy));
+
+  if (!priv->paintable || !priv->zoomable)
+    return;
+
+  /* TODO: We should probably use the step increment or something from the
+   *       adjustment to control the scaling granularity? */
+
+  /* TODO: We might want to only conditionally zoom in here, e.g. when
+   * CTRL or SHIFT are pressed. */
+
+  gtk_image_view_get_current_state (self, &state);
+
+  gtk_image_view_set_scale_internal (self, new_scale);
+
+  if (priv->hadjustment && priv->vadjustment)
+    {
+      /*priv->mouse_x = 100;*/
+      /*priv->mouse_y = 200;*/
+      gtk_image_view_fix_anchor2 (self, priv->mouse_x, priv->mouse_y, &state);
+    }
+}
+
+static void
+motion_controller_motion_cb (GtkEventControllerMotion *controller,
+                             double                    x,
+                             double                    y,
+                             gpointer                  user_data)
+{
+  GtkImageView *self = user_data;
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  priv->mouse_x = x;
+  priv->mouse_y = y;
+}
+
+static void
+gtk_image_view_ensure_gestures (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->zoomable && priv->zoom_gesture == NULL)
+    {
+      priv->zoom_gesture = gtk_gesture_zoom_new ();
+      g_signal_connect (priv->zoom_gesture, "scale-changed",
+                        (GCallback)gesture_zoom_changed_cb, self);
+      g_signal_connect (priv->zoom_gesture, "begin",
+                        (GCallback)gesture_zoom_begin_cb, self);
+      g_signal_connect (priv->zoom_gesture, "end",
+                        (GCallback)gesture_zoom_end_cb, self);
+      g_signal_connect (priv->zoom_gesture, "cancel",
+                        (GCallback)gesture_zoom_cancel_cb, self);
+      gtk_widget_add_controller (GTK_WIDGET (self),
+                                 GTK_EVENT_CONTROLLER (priv->zoom_gesture));
+
+      priv->zoom_controller = gtk_event_controller_scroll_new (GTK_EVENT_CONTROLLER_SCROLL_BOTH_AXES);
+      g_signal_connect (priv->zoom_controller, "scroll",
+                        (GCallback)scroll_controller_scroll_cb, self);
+      gtk_widget_add_controller (GTK_WIDGET (self),
+                                 priv->zoom_controller);
+
+
+      /* We only need this one for scrolling, to know the mouse position at the time of
+       * a ::scroll emission */
+      priv->motion_controller = gtk_event_controller_motion_new ();
+      g_signal_connect (priv->motion_controller, "motion", (GCallback)motion_controller_motion_cb, self);
+      gtk_widget_add_controller (GTK_WIDGET (self), priv->motion_controller);
+    }
+  else if (!priv->zoomable && priv->zoom_gesture != NULL)
+    {
+      gtk_widget_remove_controller (GTK_WIDGET (self),
+                                    GTK_EVENT_CONTROLLER (priv->zoom_gesture));
+      priv->zoom_gesture = NULL;
+
+      gtk_widget_remove_controller (GTK_WIDGET (self),
+                                    GTK_EVENT_CONTROLLER (priv->zoom_controller));
+      priv->zoom_controller = NULL;
+
+    }
+
+  if (priv->rotatable && priv->rotate_gesture == NULL)
+    {
+      priv->rotate_gesture = gtk_gesture_rotate_new ();
+      g_signal_connect (priv->rotate_gesture, "angle-changed", (GCallback)gesture_rotate_changed_cb, self);
+      g_signal_connect (priv->rotate_gesture, "begin", (GCallback)gesture_rotate_begin_cb, self);
+      g_signal_connect (priv->rotate_gesture, "end", (GCallback)gesture_rotate_end_cb, self);
+      g_signal_connect (priv->rotate_gesture, "cancel", (GCallback)gesture_rotate_cancel_cb, self);
+
+      gtk_widget_add_controller (GTK_WIDGET (self),
+                                 GTK_EVENT_CONTROLLER (priv->rotate_gesture));
+
+    }
+  else if (!priv->rotatable && priv->rotate_gesture != NULL)
+    {
+      gtk_widget_remove_controller (GTK_WIDGET (self),
+                                    GTK_EVENT_CONTROLLER (priv->rotate_gesture));
+      priv->rotate_gesture = NULL;
+    }
+
+  if (priv->zoom_gesture && priv->rotate_gesture)
+    gtk_gesture_group (priv->zoom_gesture,
+                       priv->rotate_gesture);
+}
+
+static void
+gtk_image_view_init (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  GtkWidget *widget = GTK_WIDGET (self);
+
+  gtk_widget_set_overflow (widget, GTK_OVERFLOW_HIDDEN);
+
+  priv->scale = 1.0;
+  priv->angle = 0.0;
+  priv->visible_scale = 1.0;
+  priv->visible_angle = 0.0;
+  priv->snap_angle = FALSE;
+  priv->fit_allocation = FALSE;
+  priv->scale_set = FALSE;
+  priv->anchor_x = -1;
+  priv->anchor_y = -1;
+  priv->rotatable = TRUE;
+  priv->zoomable = TRUE;
+  priv->transitions_enabled = TRUE;
+  priv->angle_transition_id = 0;
+  priv->scale_transition_id = 0;
+
+  gtk_image_view_ensure_gestures (self);
+}
+
+static void
+gtk_image_view_snapshot (GtkWidget   *widget,
+                         GtkSnapshot *snapshot)
+{
+  GtkImageView *self = GTK_IMAGE_VIEW (widget);
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  double paintable_width;
+  double paintable_height;
+  double bb_width, bb_height;
+  GskTransform *transform;
+  ViewState state;
+
+  if (!priv->paintable)
+    return;
+
+  gtk_image_view_compute_bounding_box (self,
+                                       &bb_width,
+                                       &bb_height,
+                                       &paintable_width,
+                                       &paintable_height);
+
+  gtk_image_view_get_current_state (self, &state);
+  transform = gtk_image_view_get_transform (self, &state);
+
+  gtk_snapshot_save (snapshot);
+  gtk_snapshot_transform (snapshot, transform);
+  gdk_paintable_snapshot (priv->paintable, snapshot, paintable_width, paintable_height);
+  gtk_snapshot_restore (snapshot);
+
+  gtk_snapshot_append_color (snapshot,
+                             &(GdkRGBA){1, 0, 0, 1},
+                             &GRAPHENE_RECT_INIT (priv->anchor_x - 2,
+                                                  priv->anchor_y - 2,
+                                                  4,4));
+
+  gsk_transform_unref (transform);
+}
+
+static void
+gtk_image_view_set_hadjustment (GtkImageView  *self,
+                                GtkAdjustment *hadjustment)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->hadjustment && priv->hadjustment == hadjustment)
+    return;
+
+  if (priv->hadjustment)
+    {
+      g_signal_handlers_disconnect_by_func (priv->hadjustment, adjustment_value_changed_cb, self);
+      g_object_unref (priv->hadjustment);
+    }
+
+  if (hadjustment)
+    {
+      g_signal_connect (G_OBJECT (hadjustment), "value-changed",
+                        G_CALLBACK (adjustment_value_changed_cb), self);
+      priv->hadjustment = g_object_ref_sink (hadjustment);
+    }
+  else
+    {
+      priv->hadjustment = hadjustment;
+    }
+
+  g_object_notify (G_OBJECT (self), "hadjustment");
+
+  gtk_image_view_update_adjustments (self);
+
+  gtk_image_view_invalidate (self);
+}
+
+static void
+gtk_image_view_set_vadjustment (GtkImageView  *self,
+                                GtkAdjustment *vadjustment)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->vadjustment == vadjustment)
+    return;
+
+  if (priv->vadjustment)
+    {
+      g_signal_handlers_disconnect_by_func (priv->vadjustment, adjustment_value_changed_cb, self);
+      g_object_unref (priv->vadjustment);
+    }
+
+  if (vadjustment)
+    {
+      g_signal_connect (G_OBJECT (vadjustment), "value-changed",
+                        G_CALLBACK (adjustment_value_changed_cb), self);
+      priv->vadjustment = g_object_ref_sink (vadjustment);
+    }
+  else
+    {
+      priv->vadjustment = vadjustment;
+    }
+
+  g_object_notify (G_OBJECT (self), "vadjustment");
+
+  gtk_image_view_update_adjustments (self);
+
+  gtk_image_view_invalidate (self);
+}
+
+static void
+gtk_image_view_set_hscroll_policy (GtkImageView        *self,
+                                   GtkScrollablePolicy  hscroll_policy)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->hscroll_policy == hscroll_policy)
+    return;
+
+  priv->hscroll_policy = hscroll_policy;
+  g_object_notify (G_OBJECT (self), "hscroll-policy");
+}
+
+static void
+gtk_image_view_set_vscroll_policy (GtkImageView        *self,
+                                   GtkScrollablePolicy  vscroll_policy)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->vscroll_policy == vscroll_policy)
+    return;
+
+  priv->vscroll_policy = vscroll_policy;
+  g_object_notify (G_OBJECT (self), "vscroll-policy");
+}
+
+/**
+ * gtk_image_view_set_scale:
+ * @self: A #GtkImageView instance
+ * @scale: The new scale value
+ *
+ * Sets the value of the #scale property. This will cause the
+ * #scale-set property to be set to #FALSE as well
+ *
+ * If #GtkImageView:fit-allocation is %TRUE, it will be set to %FALSE, and @self
+ * will be resized to the image's current size, taking the new scale into
+ * account.
+ *
+ * If #GtkImageView:transitions-enabled is set to %TRUE, the internal scale value will be
+ * interpolated between the old and the new scale, gtk_image_view_get_scale()
+ * will report the one passed to gtk_image_view_set_scale() however.
+ *
+ * When calling this function, #GtkImageView will try to keep the currently centered
+ * point of the image where it is, so visually it will "zoom" into the current
+ * center of the widget. Note that #GtkImageView is a #GtkScrollable, so the center
+ * of the image is also the center of the scrolled window in case it is packed into
+ * a #GtkScrolledWindow.
+ */
+void
+gtk_image_view_set_scale (GtkImageView *self,
+                          double        scale)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  ViewState state;
+
+  g_return_if_fail (GTK_IS_IMAGE_VIEW (self));
+  g_return_if_fail (scale > 0.0);
+
+  if (scale == priv->scale)
+    return;
+
+  gtk_image_view_get_current_state (self, &state);
+
+  priv->scale = scale;
+  g_object_notify_by_pspec (G_OBJECT (self),
+                            widget_props[PROP_SCALE]);
+
+  if (gtk_image_view_transitions_enabled (self))
+    gtk_image_view_animate_to_scale (self);
+
+  if (priv->scale_set)
+    {
+      priv->scale_set = FALSE;
+      g_object_notify_by_pspec (G_OBJECT (self),
+                                widget_props[PROP_SCALE_SET]);
+    }
+
+  if (priv->fit_allocation)
+    {
+      priv->fit_allocation = FALSE;
+      g_object_notify_by_pspec (G_OBJECT (self),
+                                widget_props[PROP_FIT_ALLOCATION]);
+    }
+
+
+  if (!priv->paintable)
+    return;
+
+  if (priv->hadjustment != NULL && priv->vadjustment != NULL)
+    {
+      gtk_image_view_fix_anchor2 (self,
+                                 gtk_widget_get_width (GTK_WIDGET (self)) / 2,
+                                 gtk_widget_get_height (GTK_WIDGET (self)) / 2,
+                                 &state);
+    }
+
+  gtk_image_view_update_adjustments (self);
+
+  gtk_image_view_invalidate (self);
+}
+
+/**
+ * gtk_image_view_get_scale:
+ * @self: A #GtkImageView instance
+ *
+ * Returns: The current value of the #GtkImageView:scale property.
+ */
+double
+gtk_image_view_get_scale (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_val_if_fail (GTK_IS_IMAGE_VIEW (self), 0.0);
+
+  return priv->scale;
+}
+
+/**
+ * gtk_image_view_set_angle:
+ * @self: A #GtkImageView instance
+ * @angle: The angle to rotate the image about, in
+ *   degrees. If this is < 0 or > 360, the value will
+ *   be wrapped. So e.g. setting this to 362 will result in a
+ *   angle of 2, setting it to -2 will result in 358.
+ *   Both 0 and 360 are possible.
+ *
+ * Sets the value of the #GtkImageView:angle property. When calling this function,
+ * #GtkImageView will try to keep the currently centered point of the image where it is,
+ * so visually the image will not be rotated around its center, but around the current
+ * center of the widget. Note that #GtkImageView is a #GtkScrollable, so the center
+ * of the image is also the center of the scrolled window in case it is packed into
+ * a #GtkScrolledWindow.
+ */
+void
+gtk_image_view_set_angle (GtkImageView *self,
+                          double        angle)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+  ViewState state;
+
+  g_return_if_fail (GTK_IS_IMAGE_VIEW (self));
+
+  if (angle == priv->angle)
+    return;
+
+  gtk_image_view_get_current_state (self, &state);
+
+  angle = gtk_image_view_clamp_angle (angle);
+
+  if (priv->snap_angle)
+    priv->angle = gtk_image_view_get_snapped_angle (angle);
+  else
+    priv->angle = angle;
+
+  if (gtk_image_view_transitions_enabled (self) &&
+      ABS(gtk_image_view_clamp_angle (angle) - priv->angle) > ANGLE_TRANSITION_MIN_DELTA)
+    {
+      gtk_image_view_animate_to_angle (self, angle > priv->angle);
+    }
+
+  g_object_notify_by_pspec (G_OBJECT (self),
+                            widget_props[PROP_ANGLE]);
+
+  if (!priv->paintable)
+    return;
+
+  if (priv->hadjustment && priv->vadjustment && !priv->fit_allocation)
+    {
+      gtk_image_view_fix_anchor2 (self,
+                                 gtk_widget_get_width (GTK_WIDGET (self)) / 2,
+                                 gtk_widget_get_height (GTK_WIDGET (self)) / 2,
+                                 &state);
+    }
+
+  gtk_image_view_invalidate (self);
+
+  gtk_image_view_update_adjustments (self);
+}
+
+/**
+ * gtk_image_view_get_angle:
+ * @self: A #GtkImageView instance
+ *
+ * Returns: The current angle value.
+ */
+double
+gtk_image_view_get_angle (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_val_if_fail (GTK_IS_IMAGE_VIEW (self), 0.0);
+
+  return priv->angle;
+}
+
+/**
+ * gtk_image_view_set_snap_angle:
+ * @self: A #GtkImageView instance
+ * @snap_angle: The new value of the #GtkImageView:snap-angle property
+ *
+ * Setting #snap-angle to %TRUE will cause @self's  angle to
+ * be snapped to 90° steps. Setting the #GtkImageView:angle property will cause it to
+ * be set to the closest 90° step, so e.g. using an angle of 40 will result
+ * in an angle of 0, using 240 will result in 270, etc.
+ */
+void
+gtk_image_view_set_snap_angle (GtkImageView *self,
+                               gboolean     snap_angle)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_if_fail (GTK_IS_IMAGE_VIEW (self));
+
+  snap_angle = !!snap_angle;
+
+  if (snap_angle == priv->snap_angle)
+    return;
+
+  priv->snap_angle = snap_angle;
+  g_object_notify_by_pspec (G_OBJECT (self),
+                            widget_props[PROP_SNAP_ANGLE]);
+
+  if (priv->snap_angle)
+    {
+      gtk_image_view_do_snapping (self);
+      g_object_notify_by_pspec (G_OBJECT (self),
+                                widget_props[PROP_ANGLE]);
+    }
+}
+
+/**
+ * gtk_image_view_get_snap_angle:
+ * @self: A #GtkImageView instance
+ *
+ * Returns: The current value of the #GtkImageView:snap-angle property.
+ */
+gboolean
+gtk_image_view_get_snap_angle (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_val_if_fail (GTK_IS_IMAGE_VIEW (self), FALSE);
+
+  return priv->snap_angle;
+}
+
+/**
+ * gtk_image_view_set_fit_allocation:
+ * @self: A #GtkImageView instance
+ * @fit_allocation: The new value of the #GtkImageView:fit-allocation property.
+ *
+ * Setting #GtkImageView:fit-allocation to %TRUE will cause the image to be scaled
+ * to the widget's allocation, unless it would cause the image to be
+ * scaled up.
+ *
+ * Setting #GtkImageView:fit-allocation will have the side effect of setting
+ * #scale-set set to %FALSE, thus giving the #GtkImageView the control
+ * over the image's scale. Additionally, if the new #GtkImageView:fit-allocation
+ * value is %FALSE, the scale will be reset to 1.0 and the #GtkImageView
+ * will be resized to take at least the image's real size.
+ */
+void
+gtk_image_view_set_fit_allocation (GtkImageView *self,
+                                   gboolean      fit_allocation)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_if_fail (GTK_IS_IMAGE_VIEW (self));
+
+  fit_allocation = !!fit_allocation;
+
+  if (fit_allocation == priv->fit_allocation)
+    return;
+
+  priv->fit_allocation = fit_allocation;
+  g_object_notify_by_pspec (G_OBJECT (self),
+                            widget_props[PROP_FIT_ALLOCATION]);
+
+  if (priv->scale_set)
+    {
+      priv->scale_set = FALSE;
+      g_object_notify_by_pspec (G_OBJECT (self),
+                                widget_props[PROP_SCALE_SET]);
+    }
+
+  if (!priv->fit_allocation)
+    {
+      priv->scale = 1.0;
+      g_object_notify_by_pspec (G_OBJECT (self),
+                                widget_props[PROP_SCALE]);
+    }
+
+  gtk_image_view_update_adjustments (self);
+
+  /* We always need to queue a resize here */
+  gtk_widget_queue_resize (GTK_WIDGET (self));
+}
+
+/**
+ * gtk_image_view_get_fit_allocation:
+ * @self: A #GtkImageView instance
+ *
+ * Returns: The current value of the #GtkImageView:fit-allocation property.
+ */
+gboolean
+gtk_image_view_get_fit_allocation (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_val_if_fail (GTK_IS_IMAGE_VIEW (self), FALSE);
+
+  return priv->fit_allocation;
+}
+
+/**
+ * gtk_image_view_set_rotatable:
+ * @self: A #GtkImageView instance
+ * @rotatable: The new value of the #GtkImageView:rotatable property
+ *
+ * Sets the value of the #GtkImageView:rotatable property to @rotatable. This controls whether
+ * the user can change the angle of the displayed image using a two-finger gesture.
+ */
+void
+gtk_image_view_set_rotatable (GtkImageView *self,
+                              gboolean      rotatable)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_if_fail (GTK_IS_IMAGE_VIEW (self));
+
+  rotatable = !!rotatable;
+
+  if (priv->rotatable != rotatable)
+    {
+      priv->rotatable = rotatable;
+      gtk_image_view_ensure_gestures (self);
+      g_object_notify_by_pspec (G_OBJECT (self),
+                                widget_props[PROP_ROTATABLE]);
+    }
+}
+
+  double bb_width, bb_height;
+
+/**
+ * gtk_image_view_get_rotatable:
+ * @self: A #GtkImageView instance
+ *
+ * Returns: The current value of the #GtkImageView:rotatable property
+ */
+gboolean
+gtk_image_view_get_rotatable (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_val_if_fail (GTK_IS_IMAGE_VIEW (self), FALSE);
+
+  return priv->rotatable;
+}
+
+/**
+ * gtk_image_view_set_zoomable:
+ * @self: A #GtkImageView instance
+ * @zoomable: The new value of the #GtkImageView:zoomable property
+ *
+ * Sets the new value of the #GtkImageView:zoomable property. This controls whether the user can
+ * change the #GtkImageView:scale property using a two-finger gesture.
+ */
+void
+gtk_image_view_set_zoomable (GtkImageView *self,
+                             gboolean      zoomable)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_if_fail (GTK_IS_IMAGE_VIEW (self));
+
+  zoomable = !!zoomable;
+
+  if (zoomable != priv->zoomable)
+    {
+      priv->zoomable = zoomable;
+      gtk_image_view_ensure_gestures (self);
+      g_object_notify_by_pspec (G_OBJECT (self),
+                                widget_props[PROP_ZOOMABLE]);
+    }
+}
+
+/**
+ * gtk_image_view_get_zoomable:
+ * @self: A #GtkImageView instance
+ *
+ * Returns: The current value of the #GtkImageView:zoomable property.
+ */
+gboolean
+gtk_image_view_get_zoomable (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_val_if_fail (GTK_IS_IMAGE_VIEW (self), FALSE);
+
+  return priv->zoomable;
+}
+
+/**
+ * gtk_image_view_set_transitions_enabled:
+ * @self: A #GtkImageView instance
+ * @transitions_enabled: The new value of the #GtkImageView:transitions-enabled property
+ *
+ * Sets the new value of the #GtkImageView:transitions-enabled property.
+ * Note that even if #GtkImageView:transitions-enabled is %TRUE, transitions will
+ * not be used if #GtkSettings:gtk-enable-animations is %FALSE.
+ */
+void
+gtk_image_view_set_transitions_enabled (GtkImageView *self,
+                                        gboolean      transitions_enabled)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_if_fail (GTK_IS_IMAGE_VIEW (self));
+
+  transitions_enabled = !!transitions_enabled;
+
+  if (transitions_enabled != priv->transitions_enabled)
+    {
+      priv->transitions_enabled = transitions_enabled;
+      g_object_notify_by_pspec (G_OBJECT (self),
+                                widget_props[PROP_TRANSITIONS_ENABLED]);
+    }
+}
+
+/**
+ * gtk_image_view_get_transitions_enabled:
+ * @self: A #GtkImageView instance
+ *
+ * Returns: the current value of the #GtkImageView:transitions-enabled property.
+ */
+gboolean
+gtk_image_view_get_transitions_enabled (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_val_if_fail (GTK_IS_IMAGE_VIEW (self), FALSE);
+
+  return priv->transitions_enabled;
+}
+
+/**
+ * gtk_image_view_get_scale_set:
+ * @self: A #GtkImageView instance
+ *
+ * Returns: the current value of the #GtkImageView:scale-set property.
+ */
+gboolean
+gtk_image_view_get_scale_set (GtkImageView *self)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_return_val_if_fail (GTK_IS_IMAGE_VIEW (self), FALSE);
+
+  return priv->scale_set;
+}
+
+static void
+gtk_image_view_size_allocate (GtkWidget *widget,
+                              int        width,
+                              int        height,
+                              int        baseline)
+{
+  GtkImageView *self = GTK_IMAGE_VIEW (widget);
+
+  gtk_image_view_update_adjustments (self);
+}
+
+static void
+adjustment_value_changed_cb (GtkAdjustment *adjustment,
+                             gpointer       user_data)
+{
+  GtkImageView *self = user_data;
+
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+static void
+gtk_image_view_measure (GtkWidget      *widget,
+                        GtkOrientation  orientation,
+                        int             for_size,
+                        int            *minimum,
+                        int            *natural,
+                        int            *minimum_baseline,
+                        int            *natural_baselien)
+{
+  GtkImageView *self  = GTK_IMAGE_VIEW (widget);
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->fit_allocation && priv->paintable)
+    {
+      *minimum = 0;
+      // XXX We should probably also call compute_concrete_size in here?
+
+      if (orientation == GTK_ORIENTATION_HORIZONTAL)
+        {
+          *natural = gdk_paintable_get_intrinsic_width (priv->paintable);
+        }
+      else /* VERTICAL */
+        {
+          *natural = gdk_paintable_get_intrinsic_height (priv->paintable);
+        }
+    }
+  else
+    {
+      double width, height;
+
+      gtk_image_view_compute_bounding_box (self,
+                                           &width,
+                                           &height,
+                                           NULL,
+                                           NULL);
+
+      if (orientation == GTK_ORIENTATION_HORIZONTAL)
+        {
+          *minimum = (int)ceil (width);
+          *natural = (int)ceil (width);
+        }
+      else /* VERTICAL */
+        {
+          *minimum = (int)ceil (height);
+          *natural = (int)ceil (height);
+        }
+    }
+}
+
+static void
+gtk_image_view_set_property (GObject      *object,
+                             guint         prop_id,
+                             const GValue *value,
+                             GParamSpec   *pspec)
+
+{
+  GtkImageView *self = (GtkImageView *) object;
+
+  switch (prop_id)
+    {
+      case PROP_SCALE:
+        gtk_image_view_set_scale (self, g_value_get_double (value));
+        break;
+      case PROP_ANGLE:
+        gtk_image_view_set_angle (self, g_value_get_double (value));
+        break;
+      case PROP_SNAP_ANGLE:
+        gtk_image_view_set_snap_angle (self, g_value_get_boolean (value));
+        break;
+      case PROP_FIT_ALLOCATION:
+        gtk_image_view_set_fit_allocation (self, g_value_get_boolean (value));
+        break;
+      case PROP_ROTATABLE:
+        gtk_image_view_set_rotatable (self, g_value_get_boolean (value));
+        break;
+      case PROP_ZOOMABLE:
+        gtk_image_view_set_zoomable (self, g_value_get_boolean (value));
+        break;
+      case PROP_TRANSITIONS_ENABLED:
+        gtk_image_view_set_transitions_enabled (self, g_value_get_boolean (value));
+        break;
+      case PROP_HADJUSTMENT:
+        gtk_image_view_set_hadjustment (self, g_value_get_object (value));
+        break;
+       case PROP_VADJUSTMENT:
+        gtk_image_view_set_vadjustment (self, g_value_get_object (value));
+        break;
+      case PROP_HSCROLL_POLICY:
+        gtk_image_view_set_hscroll_policy (self, g_value_get_enum (value));
+        break;
+      case PROP_VSCROLL_POLICY:
+        gtk_image_view_set_vscroll_policy (self, g_value_get_enum (value));
+        break;
+      default:
+        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+gtk_image_view_get_property (GObject    *object,
+                             guint       prop_id,
+                             GValue     *value,
+                             GParamSpec *pspec)
+{
+  GtkImageView *self  = (GtkImageView *)object;
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  switch (prop_id)
+    {
+      case PROP_SCALE:
+        g_value_set_double (value, priv->scale);
+        break;
+      case PROP_SCALE_SET:
+        g_value_set_boolean (value, priv->scale_set);
+        break;
+      case PROP_ANGLE:
+        g_value_set_double (value, priv->angle);
+        break;
+      case PROP_SNAP_ANGLE:
+        g_value_set_boolean (value, priv->snap_angle);
+        break;
+      case PROP_FIT_ALLOCATION:
+        g_value_set_boolean (value, priv->fit_allocation);
+        break;
+      case PROP_ROTATABLE:
+        g_value_set_boolean (value, priv->rotatable);
+        break;
+      case PROP_ZOOMABLE:
+        g_value_set_boolean (value, priv->zoomable);
+        break;
+      case PROP_TRANSITIONS_ENABLED:
+        g_value_set_boolean (value, priv->transitions_enabled);
+        break;
+      case PROP_HADJUSTMENT:
+        g_value_set_object (value, priv->hadjustment);
+        break;
+      case PROP_VADJUSTMENT:
+        g_value_set_object (value, priv->vadjustment);
+        break;
+      case PROP_HSCROLL_POLICY:
+        g_value_set_enum (value, priv->hscroll_policy);
+        break;
+      case PROP_VSCROLL_POLICY:
+        g_value_set_enum (value, priv->vscroll_policy);
+        break;
+      default:
+        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+gtk_image_view_finalize (GObject *object)
+{
+  GtkImageView *self  = (GtkImageView *)object;
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  g_clear_object (&priv->hadjustment);
+  g_clear_object (&priv->vadjustment);
+
+  if (priv->paintable)
+    {
+      g_signal_handlers_disconnect_by_func (priv->paintable,
+                                            G_CALLBACK (paintable_contents_changed_cb), self);
+      g_clear_object (&priv->paintable);
+    }
+
+  G_OBJECT_CLASS (gtk_image_view_parent_class)->finalize (object);
+}
+
+static void
+gtk_image_view_class_init (GtkImageViewClass *view_class)
+{
+  GObjectClass   *object_class = G_OBJECT_CLASS (view_class);
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (view_class);
+
+  object_class->set_property = gtk_image_view_set_property;
+  object_class->get_property = gtk_image_view_get_property;
+  object_class->finalize     = gtk_image_view_finalize;
+
+  widget_class->measure       = gtk_image_view_measure;
+  widget_class->size_allocate = gtk_image_view_size_allocate;
+  widget_class->snapshot      = gtk_image_view_snapshot;
+
+  /**
+   * GtkImageView:scale:
+   * The scale the internal surface gets drawn with.
+   */
+  widget_props[PROP_SCALE] = g_param_spec_double ("scale",
+                                                  P_("Scale"),
+                                                  P_("The scale the internal surface gets drawn with"),
+                                                  0.0,
+                                                  G_MAXDOUBLE,
+                                                  1.0,
+                                                  GTK_PARAM_READWRITE|G_PARAM_EXPLICIT_NOTIFY);
+  /**
+   * GtkImageView:scale-set:
+   * Whether or not the current value of the scale property was set by the user.
+   * This is to distringuish between scale values set by the #GtkImageView itself,
+   * e.g. when #GtkImageView:fit-allocation is true, which will change the scale
+   * depending on the widget allocation.
+   */
+  widget_props[PROP_SCALE_SET] = g_param_spec_boolean ("scale-set",
+                                                       P_("Scale Set"),
+                                                       P_("Wheter the scale property has been set by the 
user or by GtkImageView itself"),
+                                                       FALSE,
+                                                       GTK_PARAM_READABLE|G_PARAM_EXPLICIT_NOTIFY);
+  /**
+   * GtkImageView:angle:
+   * The angle the surface gets rotated about.
+   * This is in degrees and we rotate clock-wise.
+   */
+  widget_props[PROP_ANGLE] = g_param_spec_double ("angle",
+                                                  P_("Angle"),
+                                                  P_("The angle the internal surface gets rotated about"),
+                                                  0.0,
+                                                  360.0,
+                                                  0.0,
+                                                  GTK_PARAM_READWRITE|G_PARAM_EXPLICIT_NOTIFY);
+  /**
+   * GtkImageView:rotatable:
+   * Whether or not the image can be rotated using a two-finger rotate gesture.
+   */
+  widget_props[PROP_ROTATABLE] = g_param_spec_boolean ("rotatable",
+                                                       P_("Rotatable"),
+                                                       P_("Controls user-rotatability"),
+                                                       TRUE,
+                                                       GTK_PARAM_READWRITE|G_PARAM_EXPLICIT_NOTIFY);
+/**
+   * GtkImageView:zoomable:
+   * Whether or not the image can be scaled using a two-finger zoom gesture, as well as
+   * scrolling on the #GtkImageView.
+   */
+  widget_props[PROP_ZOOMABLE] = g_param_spec_boolean ("zoomable",
+                                                      P_("Zoomable"),
+                                                      P_("Controls user-zoomability"),
+                                                      TRUE,
+                                                      GTK_PARAM_READWRITE|G_PARAM_EXPLICIT_NOTIFY);
+/**
+   * GtkImageView:snap-angle:
+   * Whether or not the angle property snaps to 90° steps. If this is enabled
+   * and the angle property gets set to a non-90° step, the new value will be
+   * set to the closest 90° step. If #GtkImageView:transitions-enabled is %TRUE,
+   * the angle change from the current angle to the new angle will be interpolated.
+   */
+  widget_props[PROP_SNAP_ANGLE] = g_param_spec_boolean ("snap-angle",
+                                                        P_("Snap Angle"),
+                                                        P_("Snap angle to 90° steps"),
+                                                        FALSE,
+                                                        GTK_PARAM_READWRITE|G_PARAM_EXPLICIT_NOTIFY);
+
+  /**
+   * GtkImageView:fit-allocation:
+   * If this is %TRUE, the scale the image will be drawn in will depend on the current
+   * widget allocation. The image will be scaled down to fit into the widget allocation,
+   * but never scaled up. The aspect ratio of the image will be kept at all times.
+   */
+  widget_props[PROP_FIT_ALLOCATION] = g_param_spec_boolean ("fit-allocation",
+                                                            P_("Fit Allocation"),
+                                                            P_("Scale the image down to fit into the widget 
allocation"),
+                                                            FALSE,
+                                                            GTK_PARAM_READWRITE|G_PARAM_EXPLICIT_NOTIFY);
+
+  /**
+   *  GtkImageView:transitions-enabled
+   *
+   *  Whether or not certain property changes will be interpolated. This affects a variety
+   *  of function calls on a #GtkImageView instance, e.g. setting the angle property, the
+   *  scale property, but also the angle snapping in case #GtkImageView:snap-angle is set.
+   *
+   *  Note that the transitions in #GtkImageView never apply to the actual property values
+   *  set and instead interpolate between the visual angle/scale, so you cannot depend on
+   *  getting 60 notify signal emissions per second.
+   */
+  widget_props[PROP_TRANSITIONS_ENABLED] = g_param_spec_boolean ("transitions-enabled",
+                                                                 P_("Transitions Enabled"),
+                                                                 P_("Whether scale and angle changes get 
interpolated"),
+                                                                 TRUE,
+                                                                 
GTK_PARAM_READWRITE|G_PARAM_EXPLICIT_NOTIFY);
+
+  g_object_class_install_properties (object_class, LAST_WIDGET_PROPERTY, widget_props);
+
+  g_object_class_override_property (object_class, PROP_HADJUSTMENT,    "hadjustment");
+  g_object_class_override_property (object_class, PROP_VADJUSTMENT,    "vadjustment");
+  g_object_class_override_property (object_class, PROP_HSCROLL_POLICY, "hscroll-policy");
+  g_object_class_override_property (object_class, PROP_VSCROLL_POLICY, "vscroll-policy");
+
+  gtk_widget_class_set_css_name (widget_class, "imageview");
+}
+
+/**
+ * gtk_image_view_new:
+ *
+ * Returns: A newly created #GtkImageView instance.
+ */
+GtkWidget *
+gtk_image_view_new (void)
+{
+  return g_object_new (GTK_TYPE_IMAGE_VIEW, NULL);
+}
+
+static void
+gtk_image_view_replace_paintable (GtkImageView *self,
+                                  GdkPaintable *paintable)
+{
+  GtkImageViewPrivate *priv = gtk_image_view_get_instance_private (self);
+
+  if (priv->paintable)
+    {
+      g_signal_handlers_disconnect_by_func (priv->paintable, G_CALLBACK (paintable_contents_changed_cb), 
self);
+      g_object_unref (priv->paintable);
+    }
+
+  priv->paintable = paintable;
+
+  if (priv->paintable)
+    {
+      g_object_ref (priv->paintable);
+      g_signal_connect (priv->paintable, "invalidate-contents",
+                        G_CALLBACK (paintable_contents_changed_cb), self);
+    }
+
+  gtk_image_view_update_adjustments (self);
+
+  gtk_image_view_invalidate (self);
+}
+
+static GdkPaintable *
+gtk_image_view_load_image_from_stream (GtkImageView *self,
+                                       GInputStream *input_stream,
+                                       GCancellable *cancellable,
+                                       GError       *error)
+{
+  GdkPixbufAnimation *result;
+  GdkPaintable *paintable = NULL;
+
+  g_assert (error == NULL);
+  result = gdk_pixbuf_animation_new_from_stream (input_stream,
+                                                 cancellable,
+                                                 &error);
+
+  if (!error)
+    {
+      GdkPixbuf *frame = gdk_pixbuf_animation_get_static_image (result);
+
+      paintable = GDK_PAINTABLE (gdk_texture_new_for_pixbuf (frame));
+      g_object_unref (result);
+    }
+
+  g_input_stream_close (input_stream, NULL, NULL);
+  g_object_unref (input_stream);
+
+  return paintable;
+}
+
+/* CALLED FROM ANOTHER THREAD */
+static void
+gtk_image_view_load_image_contents (GTask        *task,
+                                    gpointer      source_object,
+                                    gpointer      task_data,
+                                    GCancellable *cancellable)
+{
+  GtkImageView *self = source_object;
+  GFile *file = G_FILE (task_data);
+  GFileInputStream *in_stream;
+  GdkPaintable *paintable;
+  GError *error = NULL;
+
+  in_stream = g_file_read (file, cancellable, &error);
+
+  if (error)
+    {
+      /* in_stream is NULL */
+      g_task_return_error (task, error);
+      return;
+    }
+
+  /* Closes and unrefs the input stream */
+  paintable = gtk_image_view_load_image_from_stream (self,
+                                                     G_INPUT_STREAM (in_stream),
+                                                     cancellable,
+                                                     error);
+
+  if (error)
+    g_task_return_error (task, error);
+  else
+    g_task_return_pointer (task, paintable, NULL);
+}
+
+/* CALLED FROM ANOTHER THREAD */
+static void
+gtk_image_view_load_from_input_stream (GTask        *task,
+                                       gpointer      source_object,
+                                       gpointer      task_data,
+                                       GCancellable *cancellable)
+{
+  GtkImageView *self = source_object;
+  GInputStream *in_stream = task_data;
+  GdkPaintable *paintable;
+  GError *error = NULL;
+
+  /* Closes and unrefs the input stream */
+  paintable = gtk_image_view_load_image_from_stream (self,
+                                                     in_stream,
+                                                     cancellable,
+                                                     error);
+
+  if (error)
+    g_task_return_error (task, error);
+  else
+    g_task_return_pointer (task, paintable, NULL);
+}
+
+/**
+ * gtk_image_view_load_from_file_async:
+ * @self: A #GtkImageView instance
+ * @file: (transfer full): The file to read from
+ * @cancellable: (nullable): A #GCancellable that can be used to
+ *   cancel the loading operation
+ * @callback: (scope async): Callback to call once the operation finished
+ * @user_data: (closure): Data to pass to @callback
+ *
+ * Asynchronously loads an image from the given file.
+ */
+void
+gtk_image_view_load_from_file_async (GtkImageView        *self,
+                                     GFile               *file,
+                                     GCancellable        *cancellable,
+                                     GAsyncReadyCallback  callback,
+                                     gpointer             user_data)
+{
+  GTask *task;
+
+  g_return_if_fail (GTK_IS_IMAGE_VIEW (self));
+  g_return_if_fail (G_IS_FILE (file));
+
+  task = g_task_new (self, cancellable, callback, user_data);
+  g_task_set_task_data (task, g_object_ref (file), g_object_unref);
+  g_task_run_in_thread (task, gtk_image_view_load_image_contents);
+
+  g_object_unref (task);
+}
+
+/**
+ * gtk_image_view_load_from_file_finish:
+ * @self: A #GtkImageView instance
+ * @result: A #GAsyncResult
+ * @error: (nullable): Location to store error information in case the operation fails
+ *
+ * Finished an asynchronous operation started with gtk_image_view_load_from_file_async().
+ *
+ * Returns: %TRUE if the operation succeeded, %FALSE otherwise,
+ * in which case @error will be set.
+ */
+gboolean
+gtk_image_view_load_from_file_finish (GtkImageView  *self,
+                                      GAsyncResult  *result,
+                                      GError       **error)
+{
+  GdkPaintable *paintable;
+  g_return_val_if_fail (g_task_is_valid (result, self), FALSE);
+
+  paintable = g_task_propagate_pointer (G_TASK (result), error);
+  gtk_image_view_set_paintable (self, paintable);
+
+  return paintable != NULL;
+}
+
+/**
+ * gtk_image_view_load_from_stream_async:
+ * @self: A #GtkImageView instance
+ * @input_stream: (transfer full): Input stream to read from
+ * @cancellable: (nullable): The #GCancellable used to cancel the operation
+ * @callback: (scope async): A #GAsyncReadyCallback invoked when the operation finishes
+ * @user_data: (closure): The data to pass to @callback
+ *
+ * Asynchronously loads an image from the given input stream.
+ */
+void
+gtk_image_view_load_from_stream_async (GtkImageView        *self,
+                                       GInputStream        *input_stream,
+                                       GCancellable        *cancellable,
+                                       GAsyncReadyCallback  callback,
+                                       gpointer             user_data)
+{
+  GTask *task;
+
+  g_return_if_fail (GTK_IS_IMAGE_VIEW (self));
+  g_return_if_fail (G_IS_INPUT_STREAM (input_stream));
+
+  task = g_task_new (self, cancellable, callback, user_data);
+  g_task_set_task_data (task, g_object_ref (input_stream), g_object_unref);
+  g_task_run_in_thread (task, gtk_image_view_load_from_input_stream);
+
+  g_object_unref (task);
+}
+
+/**
+ * gtk_image_view_load_from_stream_finish:
+ * @self: A #GtkImageView instance
+ * @result: A #GAsyncResult
+ * @error: (nullable): Location to store error information on failure
+ *
+ * Finishes an asynchronous operation started by gtk_image_view_load_from_stream_async().
+ *
+ * Returns: %TRUE if the operation finished successfully, %FALSE otherwise.
+ */
+gboolean
+gtk_image_view_load_from_stream_finish (GtkImageView  *self,
+                                        GAsyncResult  *result,
+                                        GError       **error)
+{
+  GdkPaintable *paintable;
+
+  g_return_val_if_fail (g_task_is_valid (result, self), FALSE);
+
+  paintable = g_task_propagate_pointer (G_TASK (result), error);
+  gtk_image_view_set_paintable (self, paintable);
+
+  return paintable != NULL;
+}
+
+/**
+ * gtk_image_view_set_paintable:
+ * @self: A #GtkImageView instance
+ * @paintable: (nullable): The #GdkPaintable to set, or %NULL
+ *   to unset any currently set contents
+ *
+ * Replace the current contents of the image view with the given paintable
+ */
+void
+gtk_image_view_set_paintable (GtkImageView *self,
+                              GdkPaintable *paintable)
+{
+  g_return_if_fail (GTK_IS_IMAGE_VIEW (self));
+  g_return_if_fail (paintable == NULL || GDK_IS_PAINTABLE (paintable));
+
+  gtk_image_view_replace_paintable (self, paintable);
+}
diff --git a/gtk/gtkimageview.h b/gtk/gtkimageview.h
new file mode 100644
index 0000000000..433310df5c
--- /dev/null
+++ b/gtk/gtkimageview.h
@@ -0,0 +1,116 @@
+/*  Copyright 2018 Timm Bäder
+ *
+ * GTK+ is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * GLib is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with GTK+; see the file COPYING.  If not,
+ * see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GTK_IMAGE_VIEW_H__
+#define __GTK_IMAGE_VIEW_H__
+
+#if !defined (__GTK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gtk/gtk.h> can be included directly."
+#endif
+
+#include <gtk/gtkwidget.h>
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_IMAGE_VIEW            (gtk_image_view_get_type ())
+#define GTK_IMAGE_VIEW(obj)            (G_TYPE_CHECK_INSTANCE_CAST ((obj), GTK_TYPE_IMAGE_VIEW, 
GtkImageView))
+#define GTK_IMAGE_VIEW_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST ((klass), GTK_TYPE_IMAGE_VIEW, 
GtkImageViewClass))
+#define GTK_IS_IMAGE_VIEW(obj)         (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GTK_TYPE_IMAGE_VIEW))
+#define GTK_IS_IMAGE_VIEW_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GTK_TYPE_IMAGE_VIEW))
+#define GTK_IMAGE_VIEW_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS ((obj), GTK_TYPE_IMAGE_VIEW, 
GtkImageViewClass))
+
+typedef struct _GtkImageView         GtkImageView;
+typedef struct _GtkImageViewClass    GtkImageViewClass;
+
+struct _GtkImageView
+{
+  GtkWidget parent_instance;
+};
+
+struct _GtkImageViewClass
+{
+  GtkWidgetClass parent_class;
+};
+
+
+GDK_AVAILABLE_IN_ALL
+GType         gtk_image_view_get_type               (void) G_GNUC_CONST;
+GDK_AVAILABLE_IN_ALL
+GtkWidget *   gtk_image_view_new                    (void);
+GDK_AVAILABLE_IN_ALL
+void          gtk_image_view_load_from_file_async   (GtkImageView         *self,
+                                                     GFile                *file,
+                                                     GCancellable         *cancellable,
+                                                     GAsyncReadyCallback   callback,
+                                                     gpointer              user_data);
+GDK_AVAILABLE_IN_ALL
+gboolean     gtk_image_view_load_from_file_finish   (GtkImageView         *self,
+                                                     GAsyncResult         *result,
+                                                     GError              **error);
+GDK_AVAILABLE_IN_ALL
+void         gtk_image_view_load_from_stream_async  (GtkImageView         *self,
+                                                     GInputStream         *input_stream,
+                                                     GCancellable         *cancellable,
+                                                     GAsyncReadyCallback   callback,
+                                                     gpointer              user_data);
+GDK_AVAILABLE_IN_ALL
+gboolean     gtk_image_view_load_from_stream_finish (GtkImageView         *self,
+                                                     GAsyncResult         *result,
+                                                     GError              **error);
+GDK_AVAILABLE_IN_ALL
+void         gtk_image_view_set_scale               (GtkImageView         *self,
+                                                     double                scale);
+GDK_AVAILABLE_IN_ALL
+double       gtk_image_view_get_scale               (GtkImageView         *self);
+GDK_AVAILABLE_IN_ALL
+void         gtk_image_view_set_angle               (GtkImageView         *self,
+                                                     double                angle);
+GDK_AVAILABLE_IN_ALL
+double       gtk_image_view_get_angle               (GtkImageView         *self);
+GDK_AVAILABLE_IN_ALL
+void         gtk_image_view_set_snap_angle          (GtkImageView         *self,
+                                                     gboolean              snap_angle);
+GDK_AVAILABLE_IN_ALL
+gboolean     gtk_image_view_get_snap_angle          (GtkImageView         *self);
+GDK_AVAILABLE_IN_ALL
+void         gtk_image_view_set_fit_allocation      (GtkImageView         *self,
+                                                     gboolean              fit_allocation);
+GDK_AVAILABLE_IN_ALL
+gboolean     gtk_image_view_get_fit_allocation      (GtkImageView         *self);
+GDK_AVAILABLE_IN_ALL
+void         gtk_image_view_set_rotatable           (GtkImageView         *self,
+                                                     gboolean              rotatable);
+GDK_AVAILABLE_IN_ALL
+gboolean     gtk_image_view_get_rotatable           (GtkImageView         *self);
+GDK_AVAILABLE_IN_ALL
+void         gtk_image_view_set_zoomable            (GtkImageView         *self,
+                                                     gboolean              zoomable);
+GDK_AVAILABLE_IN_ALL
+gboolean     gtk_image_view_get_zoomable            (GtkImageView         *self);
+GDK_AVAILABLE_IN_ALL
+gboolean     gtk_image_view_get_scale_set           (GtkImageView         *self);
+GDK_AVAILABLE_IN_ALL
+void         gtk_image_view_set_transitions_enabled (GtkImageView         *self,
+                                                     gboolean              transitions_enabled);
+GDK_AVAILABLE_IN_ALL
+gboolean     gtk_image_view_get_transitions_enabled (GtkImageView         *self);
+GDK_AVAILABLE_IN_ALL
+void         gtk_image_view_set_paintable           (GtkImageView         *self,
+                                                     GdkPaintable         *paintable);
+G_END_DECLS
+
+#endif
diff --git a/gtk/meson.build b/gtk/meson.build
index 3119e05934..966442b2d3 100644
--- a/gtk/meson.build
+++ b/gtk/meson.build
@@ -263,6 +263,7 @@ gtk_public_sources = files([
   'gtkiconview.c',
   'gtkimage.c',
   'gtkimagedefinition.c',
+  'gtkimageview.c',
   'gtkimcontext.c',
   'gtkimcontextsimple.c',
   'gtkimmodule.c',
@@ -527,6 +528,7 @@ gtk_public_headers = files([
   'gtkiconview.h',
   'gtkimage.h',
   'gtkimcontext.h',
+  'gtkimageview.h',
   'gtkimcontextsimple.h',
   'gtkimmodule.h',
   'gtkimmulticontext.h',
diff --git a/testsuite/gtk/imageview-size.c b/testsuite/gtk/imageview-size.c
new file mode 100644
index 0000000000..3ae81eec35
--- /dev/null
+++ b/testsuite/gtk/imageview-size.c
@@ -0,0 +1,178 @@
+#include <gtk/gtk.h>
+
+
+void
+empty ()
+{
+  int min, nat;
+  GtkWidget *iv = gtk_image_view_new ();
+  gtk_widget_show (iv);
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_HORIZONTAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, 0);
+  g_assert_cmpint (nat, ==, 0);
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_VERTICAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, 0);
+  g_assert_cmpint (nat, ==, 0);
+}
+
+void
+image_fit_allocation ()
+{
+  int min, nat;
+  GtkWidget *iv;
+  GdkPixbuf *pic;
+  GdkTexture *texture;
+
+  iv = gtk_image_view_new ();
+  pic = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, 100, 200);
+  texture = gdk_texture_new_for_pixbuf (pic);
+  gtk_image_view_set_paintable (GTK_IMAGE_VIEW (iv), GDK_PAINTABLE (texture));
+  gtk_image_view_set_fit_allocation (GTK_IMAGE_VIEW (iv), TRUE);
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_HORIZONTAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, 0);
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_width (pic));
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_VERTICAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, 0);
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_height (pic));
+}
+
+void
+image_no_fit_allocation ()
+{
+  int min, nat;
+  GtkWidget *iv;
+  GdkPixbuf *pic;
+  GdkTexture *texture;
+
+  iv = gtk_image_view_new ();
+  pic = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, 100, 200);
+  texture = gdk_texture_new_for_pixbuf (pic);
+  gtk_image_view_set_paintable (GTK_IMAGE_VIEW (iv), GDK_PAINTABLE (texture));
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_HORIZONTAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_width (pic));
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_width (pic));
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_VERTICAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_height (pic));
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_height (pic));
+}
+
+void
+image_scaled ()
+{
+  int min, nat;
+  GtkWidget *iv;
+  GdkPixbuf *pic;
+  GdkTexture *texture;
+
+  iv = gtk_image_view_new ();
+  pic = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, 100, 200);
+  texture = gdk_texture_new_for_pixbuf (pic);
+  gtk_image_view_set_paintable (GTK_IMAGE_VIEW (iv), GDK_PAINTABLE (texture));
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_HORIZONTAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_width (pic));
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_width (pic));
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_VERTICAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_height (pic));
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_height (pic));
+
+  gtk_image_view_set_scale (GTK_IMAGE_VIEW (iv), 2.0);
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_HORIZONTAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_width (pic) * 2.0);
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_width (pic) * 2.0);
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_VERTICAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_height (pic) * 2.0);
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_height (pic) * 2.0);
+
+
+  gtk_image_view_set_scale (GTK_IMAGE_VIEW (iv), 0.5);
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_HORIZONTAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_width (pic) * 0.5);
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_width (pic) * 0.5);
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_VERTICAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_height (pic) * 0.5);
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_height (pic) * 0.5);
+}
+
+void
+image_rotated ()
+{
+  int min, nat;
+  GtkWidget *iv;
+  GdkPixbuf *pic;
+  GdkTexture *texture;
+
+  iv = gtk_image_view_new ();
+  pic = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, 100, 200);
+  texture = gdk_texture_new_for_pixbuf (pic);
+  gtk_image_view_set_paintable (GTK_IMAGE_VIEW (iv), GDK_PAINTABLE (texture));
+  gtk_image_view_set_angle (GTK_IMAGE_VIEW (iv), 90.0);
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_HORIZONTAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_height (pic));
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_height (pic));
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_VERTICAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_width (pic));
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_width (pic));
+}
+
+void
+image_rotated_scaled ()
+{
+  int min, nat;
+  GtkWidget *iv;
+  GdkPixbuf *pic;
+  GdkTexture *texture;
+
+  iv = gtk_image_view_new ();
+  pic = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, 100, 200);
+  texture = gdk_texture_new_for_pixbuf (pic);
+  gtk_image_view_set_paintable (GTK_IMAGE_VIEW (iv), GDK_PAINTABLE (texture));
+  gtk_image_view_set_angle (GTK_IMAGE_VIEW (iv), 90.0);
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_HORIZONTAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_height (pic));
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_height (pic));
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_VERTICAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_width (pic));
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_width (pic));
+
+  gtk_image_view_set_scale (GTK_IMAGE_VIEW (iv), 0.5);
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_HORIZONTAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_height (pic) * 0.5);
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_height (pic) * 0.5);
+
+  gtk_widget_measure (iv, GTK_ORIENTATION_VERTICAL, -1, &min, &nat, NULL, NULL);
+  g_assert_cmpint (min, ==, gdk_pixbuf_get_width (pic) * 0.5);
+  g_assert_cmpint (nat, ==, gdk_pixbuf_get_width (pic) * 0.5);
+}
+
+int
+main (int argc, char **argv)
+{
+  gtk_init ();
+  g_test_init (&argc, &argv, NULL);
+
+  g_test_add_func ("/sizing/imageview/empty", empty);
+  g_test_add_func ("/sizing/imageview/image-fit-allocation", image_fit_allocation);
+  g_test_add_func ("/sizing/imageview/image-no-fit-allocation", image_no_fit_allocation);
+  g_test_add_func ("/sizing/imageview/image-scaled", image_scaled);
+  g_test_add_func ("/sizing/imageview/image-rotated", image_rotated);
+  g_test_add_func ("/sizing/imageview/image-rotated-scaled", image_rotated_scaled);
+
+  return g_test_run ();
+}
diff --git a/testsuite/gtk/meson.build b/testsuite/gtk/meson.build
index b02d3f51ce..470973f633 100644
--- a/testsuite/gtk/meson.build
+++ b/testsuite/gtk/meson.build
@@ -71,6 +71,7 @@ tests = [
   ['displayclose'],
   ['revealer-size'],
   ['widgetorder'],
+  ['imageview-size'],
 ]
 
 test_cargs = []


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