[gtk/wip/baedert/transforms6: 153/155] Add shrinking test case

[Timm Bäder <baedert src gnome org>]

commit 6f5c5cacfe90542f311f3e1ff5f51558e07ef3d7
Author: Timm Bäder <mail baedert org>
Date:   Mon Dec 31 13:16:40 2018 +0100

    Add shrinking test case

 tests/meson.build     |   1 +
 tests/testshrinking.c | 184 ++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 185 insertions(+)
---
diff --git a/tests/meson.build b/tests/meson.build
index c6b6d2e559..888a2457ba 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -133,6 +133,7 @@ gtk_tests = [
   ['testoutsetshadowdrawing'],
   ['testblur'],
   ['testtexture'],
+  ['testshrinking'],
 ]
 
 if os_unix
diff --git a/tests/testshrinking.c b/tests/testshrinking.c
new file mode 100644
index 0000000000..bec91fdea5
--- /dev/null
+++ b/tests/testshrinking.c
@@ -0,0 +1,184 @@
+
+#include<gtk/gtk.h>
+
+typedef struct _GtkShrink      GtkShrink;
+typedef struct _GtkShrinkClass GtkShrinkClass;
+
+#define GTK_TYPE_SHRINK           (gtk_shrink_get_type ())
+#define GTK_SHRINK(obj)           (G_TYPE_CHECK_INSTANCE_CAST(obj, GTK_TYPE_SHRINK, GtkShrink))
+#define GTK_SHRINK_CLASS(cls)     (G_TYPE_CHECK_CLASS_CAST(cls, GTK_TYPE_SHRINK, GtkShrinkClass))
+struct _GtkShrink
+{
+  GtkWidget parent_instance;
+
+  GtkWidget *child;
+};
+
+struct _GtkShrinkClass
+{
+  GtkWidgetClass parent_class;
+};
+
+GType gtk_shrink_get_type (void) G_GNUC_CONST;
+
+G_DEFINE_TYPE(GtkShrink, gtk_shrink, GTK_TYPE_WIDGET);
+
+
+static void
+gtk_shrink_measure (GtkWidget      *widget,
+                    GtkOrientation  orientation,
+                    int             for_size,
+                    int            *minimum,
+                    int            *natural,
+                    int            *minimum_baseline,
+                    int            *natural_baseline)
+{
+  GtkShrink *self = (GtkShrink *)widget;
+
+  *minimum = 0;
+
+  gtk_widget_measure (self->child, orientation, for_size, NULL, natural, NULL, NULL);
+}
+
+static void
+gtk_shrink_size_allocate (GtkWidget *widget,
+                          int        width,
+                          int        height,
+                          int        baseline)
+{
+  GtkShrink *self = (GtkShrink *)widget;
+  int child_width;
+  int child_height;
+  float scale_x;
+  float scale_y;
+  graphene_matrix_t transform;
+
+  gtk_widget_measure (self->child, GTK_ORIENTATION_HORIZONTAL, -1, &child_width, NULL, NULL, NULL);
+  gtk_widget_measure (self->child, GTK_ORIENTATION_VERTICAL, -1, &child_height, NULL, NULL, NULL);
+
+  if (width < child_width)
+    scale_x = (float)width / (float)child_width;
+  else
+    scale_x = 1.0f;
+
+  if (height < child_height)
+    scale_y = (float)height / (float)child_height;
+  else
+    scale_y = 1.0f;
+
+  graphene_matrix_init_scale (&transform, scale_x, scale_y, 1.0f);
+
+  gtk_widget_size_allocate_transformed (self->child,
+                                        MAX (width, child_width),
+                                        MAX (height, child_height),
+                                        -1, &transform);
+}
+
+static void
+gtk_shrink_finalize (GObject *object)
+{
+  GtkShrink *self = (GtkShrink *)object;
+
+  gtk_widget_unparent (self->child);
+
+  G_OBJECT_CLASS (gtk_shrink_parent_class)->finalize (object);
+}
+
+static void
+gtk_shrink_init (GtkShrink *self)
+{
+  gtk_widget_set_has_surface (GTK_WIDGET (self), FALSE);
+}
+
+static void
+gtk_shrink_class_init (GtkShrinkClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
+
+  object_class->finalize = gtk_shrink_finalize;
+
+  widget_class->measure = gtk_shrink_measure;
+  widget_class->size_allocate = gtk_shrink_size_allocate;
+}
+
+static GtkWidget *
+gtk_shrink_new (GtkWidget *child)
+{
+  GtkShrink *s = GTK_SHRINK (g_object_new (GTK_TYPE_SHRINK, NULL));
+
+  s->child = child;
+  gtk_widget_set_parent (child, GTK_WIDGET (s));
+
+  return GTK_WIDGET (s);
+}
+
+
+
+/* Stub definition of MyTextView which is used in the
+ * widget-factory.ui file. We just need this so the
+ * test keeps working
+ */
+typedef struct
+{
+  GtkTextView tv;
+} MyTextView;
+
+typedef GtkTextViewClass MyTextViewClass;
+
+G_DEFINE_TYPE (MyTextView, my_text_view, GTK_TYPE_TEXT_VIEW)
+
+static void
+my_text_view_init (MyTextView *tv) {}
+
+static void
+my_text_view_class_init (MyTextViewClass *tv_class) {}
+
+/* Copied from tests/scrolling-performance.c */
+GtkWidget *
+create_widget_factory_content (void)
+{
+  GError *error = NULL;
+  GtkBuilder *builder;
+  GtkWidget *result;
+
+  g_type_ensure (my_text_view_get_type ());
+  builder = gtk_builder_new ();
+  gtk_builder_add_from_file (builder,
+                             "../demos/widget-factory/widget-factory.ui",
+                             &error);
+  if (error != NULL)
+    g_error ("Failed to create widgets: %s", error->message);
+
+  result = GTK_WIDGET (gtk_builder_get_object (builder, "box1"));
+  g_object_ref (result);
+  gtk_container_remove (GTK_CONTAINER (gtk_widget_get_parent (result)),
+                        result);
+  g_object_unref (builder);
+
+  return result;
+}
+
+
+
+int
+main (int argc, char **argv)
+{
+  GtkWidget *window;
+  GtkWidget *shrink;
+  GtkWidget *to_shrink;
+
+  gtk_init ();
+
+  window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
+  to_shrink = create_widget_factory_content ();
+  g_object_set (G_OBJECT (to_shrink), "margin", 0, NULL);
+  shrink = gtk_shrink_new (to_shrink);
+
+  gtk_container_add (GTK_CONTAINER (window), shrink);
+
+  gtk_widget_show (window);
+  gtk_main ();
+
+  return 0;
+}