[retro-gtk/c-port: 21/42] Port CairoDisplay to C

[Adrien Plazas <aplazas src gnome org>]

commit 67e99599e31c52c8144945d5209007cb784c1175
Author: Adrien Plazas <kekun plazas laposte net>
Date:   Wed Sep 6 14:21:14 2017 +0200

    Port CairoDisplay to C

 retro-gtk/Makefile.am              |    3 +-
 retro-gtk/retro-cairo-display.c    |  403 ++++++++++++++++++++++++++++++++++++
 retro-gtk/retro-cairo-display.h    |   41 ++++
 retro-gtk/retro-core-view.c        |    1 +
 retro-gtk/video/cairo-display.vala |  143 -------------
 5 files changed, 447 insertions(+), 144 deletions(-)
---
diff --git a/retro-gtk/Makefile.am b/retro-gtk/Makefile.am
index 0a3ce17..8183b1f 100644
--- a/retro-gtk/Makefile.am
+++ b/retro-gtk/Makefile.am
@@ -32,6 +32,7 @@ BUILT_SOURCES = retro-gtk-internal.h
 retro_gtk_public_h_sources = \
        retro-analog-id.h \
        retro-analog-index.h \
+       retro-cairo-display.h \
        retro-core-view.h \
        retro-device-type.h \
        retro-gtk.h \
@@ -75,6 +76,7 @@ libretro_gtk_la_SOURCES = \
        core-error.vala \
        memory.vala \
        retro.vala \
+       retro-cairo-display.c \
        retro-core-descriptor.vala \
        retro-core-descriptor-error.vala \
        retro-core-view.c \
@@ -95,7 +97,6 @@ libretro_gtk_la_SOURCES = \
        retro-environment.c \
        libretro-environment.h \
        \
-       video/cairo-display.vala \
        video/retro-video-converter.c \
        $(NULL)
 
diff --git a/retro-gtk/retro-cairo-display.c b/retro-gtk/retro-cairo-display.c
new file mode 100644
index 0000000..fe14269
--- /dev/null
+++ b/retro-gtk/retro-cairo-display.c
@@ -0,0 +1,403 @@
+// This file is part of retro-gtk. License: GPL-3.0+.
+
+#include "retro-cairo-display.h"
+
+#include "retro-pixel-format.h"
+
+// FIXME Remove as soon as possible.
+GdkPixbuf *
+gdk_pixbuf_new_from_video (gconstpointer src,
+                           guint         width,
+                           guint         height,
+                           gsize         pitch,
+                           gint          pixel_format);
+
+/*
+ * Because gdk-pixbuf saves dpi as integer we have to multiply it by big enough
+ * number to represent aspect ratio precisely.
+ */
+#define RETRO_CAIRO_DISPLAY_Y_DPI (1000000.0f)
+
+struct _RetroCairoDisplay
+{
+  GtkDrawingArea parent_instance;
+  RetroCore *core;
+  GdkPixbuf *pixbuf;
+  RetroVideoFilter filter;
+  gfloat aspect_ratio;
+  gboolean show_surface;
+  gulong on_video_output_id;
+};
+
+G_DEFINE_TYPE (RetroCairoDisplay, retro_cairo_display, GTK_TYPE_DRAWING_AREA)
+
+enum {
+  PROP_PIXBUF = 1,
+  N_PROPS,
+};
+
+static GParamSpec *properties [N_PROPS];
+
+/* Private */
+
+static void
+retro_cairo_display_get_video_box (RetroCairoDisplay *self,
+                                   gdouble           *width,
+                                   gdouble           *height,
+                                   gdouble           *x,
+                                   gdouble           *y)
+{
+  gdouble w;
+  gdouble h;
+  gdouble display_ratio;
+  gdouble allocated_ratio;
+
+  g_return_if_fail (self != NULL);
+  g_return_if_fail (width != NULL);
+  g_return_if_fail (height != NULL);
+  g_return_if_fail (x != NULL);
+  g_return_if_fail (y != NULL);
+
+  w = (gdouble) gtk_widget_get_allocated_width (GTK_WIDGET (self));
+  h = (gdouble) gtk_widget_get_allocated_height (GTK_WIDGET (self));
+
+  // Set the size of the display.
+  display_ratio = (gdouble) self->aspect_ratio;
+  allocated_ratio = w / h;
+
+  // If the screen is wider than the video…
+  if (allocated_ratio > display_ratio) {
+    *height = h;
+    *width = (gdouble) (h * display_ratio);
+  }
+  else {
+    *width = w;
+    *height = (gdouble) (w / display_ratio);
+  }
+
+  // Set the position of the display.
+  *x = (w - *width) / 2;
+  *y = (h - *height) / 2;
+}
+
+static void
+retro_cairo_display_draw_background (RetroCairoDisplay *self,
+                                     cairo_t           *cr)
+{
+  g_return_if_fail (self != NULL);
+  g_return_if_fail (cr != NULL);
+
+  cairo_set_source_rgb (cr, (gdouble) 0, (gdouble) 0, (gdouble) 0);
+  cairo_paint (cr);
+}
+
+static gboolean
+retro_cairo_display_real_draw (GtkWidget *base,
+                               cairo_t   *cr)
+{
+  RetroCairoDisplay *self = RETRO_CAIRO_DISPLAY (base);
+  GdkPixbuf *to_draw;
+  gboolean has_alpha;
+  gint width;
+  gint height;
+
+  cairo_surface_t *surface;
+  gdouble w = 0.0;
+  gdouble h = 0.0;
+  gdouble x = 0.0;
+  gdouble y = 0.0;
+  gdouble xs;
+  gdouble ys;
+  cairo_pattern_t *source;
+
+  g_return_val_if_fail (self != NULL, FALSE);
+  g_return_val_if_fail (cr != NULL, FALSE);
+
+  retro_cairo_display_draw_background (self, cr);
+
+  if (!self->show_surface)
+    return FALSE;
+
+  if (self->pixbuf == NULL)
+    return FALSE;
+
+  if (gtk_widget_get_sensitive (GTK_WIDGET (self)))
+    to_draw = g_object_ref (self->pixbuf);
+  else {
+    has_alpha = gdk_pixbuf_get_has_alpha (self->pixbuf);
+    width = gdk_pixbuf_get_width (self->pixbuf);
+    height = gdk_pixbuf_get_height (self->pixbuf);
+    to_draw = gdk_pixbuf_new (GDK_COLORSPACE_RGB, has_alpha, 8, width, height);
+    gdk_pixbuf_saturate_and_pixelate (self->pixbuf, to_draw, 0.0f, FALSE);
+  }
+
+  surface = gdk_cairo_surface_create_from_pixbuf (to_draw, 1, NULL);
+  retro_cairo_display_get_video_box (self, &w, &h, &x, &y);
+  xs = w / gdk_pixbuf_get_width (to_draw);
+  ys = h / gdk_pixbuf_get_height (to_draw);
+
+  cairo_scale (cr, xs, ys);
+  cairo_set_source_surface (cr, surface, x / xs, y / ys);
+  source = cairo_get_source (cr);
+  switch (self->filter) {
+  case RETRO_VIDEO_FILTER_SHARP:
+    cairo_pattern_set_filter (source, CAIRO_FILTER_NEAREST);
+
+    break;
+  default:
+  case RETRO_VIDEO_FILTER_SMOOTH:
+    cairo_pattern_set_filter (source, CAIRO_FILTER_BILINEAR);
+
+    break;
+  }
+  cairo_paint (cr);
+
+  cairo_surface_destroy (surface);
+  g_object_unref (to_draw);
+
+  return TRUE;
+}
+static void
+retro_cairo_display_finalize (GObject *object)
+{
+  RetroCairoDisplay *self = (RetroCairoDisplay *) object;
+
+  if (self->core != NULL)
+    g_object_unref (self->core);
+  if (self->pixbuf != NULL)
+    g_object_unref (self->pixbuf);
+
+  G_OBJECT_CLASS (retro_cairo_display_parent_class)->finalize (object);
+}
+
+static void
+retro_cairo_display_get_property (GObject    *object,
+                                  guint       prop_id,
+                                  GValue     *value,
+                                  GParamSpec *pspec)
+{
+  RetroCairoDisplay *self = RETRO_CAIRO_DISPLAY (object);
+
+  switch (prop_id) {
+  case PROP_PIXBUF:
+    g_value_set_object (value, retro_cairo_display_get_pixbuf (self));
+
+    break;
+  default:
+    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+
+    break;
+  }
+}
+
+static void
+retro_cairo_display_set_property (GObject      *object,
+                                  guint         prop_id,
+                                  const GValue *value,
+                                  GParamSpec   *pspec)
+{
+  RetroCairoDisplay *self = RETRO_CAIRO_DISPLAY (object);
+
+  switch (prop_id) {
+  case PROP_PIXBUF:
+    retro_cairo_display_set_pixbuf (self, g_value_get_object (value));
+
+    break;
+  default:
+    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+
+    break;
+  }
+}
+
+static void
+retro_cairo_display_class_init (RetroCairoDisplayClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  ((GtkWidgetClass *) klass)->draw = (gboolean (*) (GtkWidget *, cairo_t *)) retro_cairo_display_real_draw;
+
+  object_class->finalize = retro_cairo_display_finalize;
+  object_class->get_property = retro_cairo_display_get_property;
+  object_class->set_property = retro_cairo_display_set_property;
+
+  properties[PROP_PIXBUF] =
+    g_param_spec_object ("pixbuf",
+                         "Pixbuf",
+                         "The displayed pixbuf",
+                         gdk_pixbuf_get_type (),
+                         G_PARAM_READWRITE |
+                         G_PARAM_STATIC_NAME |
+                         G_PARAM_STATIC_NICK |
+                         G_PARAM_STATIC_BLURB);
+  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_PIXBUF, properties[PROP_PIXBUF]);
+}
+
+static void
+queue_draw (GObject    *sender,
+            GParamSpec *pspec,
+            gpointer    self)
+{
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+static void
+retro_cairo_display_init (RetroCairoDisplay *self)
+{
+  self->filter = RETRO_VIDEO_FILTER_SMOOTH;
+  self->show_surface = TRUE;
+  g_signal_connect_object (G_OBJECT (self),
+                           "notify::sensitive",
+                           (GCallback) queue_draw,
+                           GTK_WIDGET (self),
+                           0);
+  g_signal_connect_object (G_OBJECT (self),
+                           "notify::pixbuf",
+                           (GCallback) queue_draw,
+                           GTK_WIDGET (self),
+                           0);
+}
+
+GdkPixbuf *
+retro_cairo_display_get_pixbuf (RetroCairoDisplay *self)
+{
+  g_return_val_if_fail (self != NULL, NULL);
+
+  return self->pixbuf;
+}
+
+void
+retro_cairo_display_set_pixbuf (RetroCairoDisplay *self,
+                                GdkPixbuf         *pixbuf)
+{
+  g_return_if_fail (self != NULL);
+
+  if (self->pixbuf == pixbuf)
+    return;
+
+  g_clear_object (&self->pixbuf);
+
+  if (pixbuf != NULL)
+    self->pixbuf = g_object_ref (pixbuf);
+
+  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_PIXBUF]);
+}
+
+static void
+retro_cairo_display_on_video_output (RetroCore        *sender,
+                                     guint8           *data,
+                                     int               data_length1,
+                                     guint             width,
+                                     guint             height,
+                                     gsize             pitch,
+                                     RetroPixelFormat  pixel_format,
+                                     gfloat            aspect_ratio,
+                                     gpointer          user_data)
+{
+  RetroCairoDisplay *self = RETRO_CAIRO_DISPLAY (user_data);
+
+  GdkPixbuf *pixbuf;
+  gfloat x_dpi;
+  gchar *x_dpi_string;
+  gchar *y_dpi_string;
+
+  g_return_if_fail (self != NULL);
+
+  self->aspect_ratio = aspect_ratio;
+  pixbuf = gdk_pixbuf_new_from_video (data, width, height, pitch, pixel_format);
+  retro_cairo_display_set_pixbuf (self, pixbuf);
+
+  if (pixbuf != NULL)
+    g_object_unref (pixbuf);
+
+  if (self->pixbuf == NULL)
+    return;
+
+  x_dpi = aspect_ratio * RETRO_CAIRO_DISPLAY_Y_DPI;
+  x_dpi_string = g_strdup_printf ("%g", x_dpi);
+  y_dpi_string = g_strdup_printf ("%g", RETRO_CAIRO_DISPLAY_Y_DPI);
+  gdk_pixbuf_set_option (self->pixbuf, "x-dpi", x_dpi_string);
+  gdk_pixbuf_set_option (self->pixbuf, "y-dpi", y_dpi_string);
+  g_free (y_dpi_string);
+  g_free (x_dpi_string);
+}
+
+void
+retro_cairo_display_set_core (RetroCairoDisplay *self,
+                              RetroCore         *core)
+{
+  g_return_if_fail (self != NULL);
+
+  if (self->core == core)
+    return;
+
+  if (self->core != NULL) {
+    g_signal_handler_disconnect (G_OBJECT (self->core), self->on_video_output_id);
+    g_clear_object (&self->core);
+  }
+
+  if (core != NULL) {
+    self->core = g_object_ref (core);
+    self->on_video_output_id = g_signal_connect_object (core, "video-output", (GCallback) 
retro_cairo_display_on_video_output, self, 0);
+  }
+}
+
+void
+retro_cairo_display_set_filter (RetroCairoDisplay *self,
+                                RetroVideoFilter   filter)
+{
+  g_return_if_fail (self != NULL);
+
+  self->filter = filter;
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+gboolean
+retro_cairo_display_get_coordinates_on_display (RetroCairoDisplay *self,
+                                                gdouble            widget_x,
+                                                gdouble            widget_y,
+                                                gdouble           *display_x,
+                                                gdouble           *display_y)
+{
+  gdouble w = 0.0;
+  gdouble h = 0.0;
+  gdouble x = 0.0;
+  gdouble y = 0.0;
+
+  g_return_val_if_fail (self != NULL, FALSE);
+  g_return_val_if_fail (display_x != NULL, FALSE);
+  g_return_val_if_fail (display_y != NULL, FALSE);
+
+  retro_cairo_display_get_video_box (self, &w, &h, &x, &y);
+
+  // Return coordinates as a [-1.0, 1.0] scale, (0.0, 0.0) is the center.
+  *display_x = ((widget_x - x) * 2.0 - w) / w;
+  *display_y = ((widget_y - y) * 2.0 - h) / h;
+
+  return (-1.0 <= *display_x) && (*display_x <= 1.0) &&
+         (-1.0 <= *display_y) && (*display_y <= 1.0);
+}
+
+void
+retro_cairo_display_show_video (RetroCairoDisplay *self)
+{
+  g_return_if_fail (self != NULL);
+
+  self->show_surface = TRUE;
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+void
+retro_cairo_display_hide_video (RetroCairoDisplay *self)
+{
+  g_return_if_fail (self != NULL);
+
+  self->show_surface = FALSE;
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+RetroCairoDisplay *
+retro_cairo_display_new (void)
+{
+  return g_object_new (RETRO_TYPE_CAIRO_DISPLAY, NULL);
+}
diff --git a/retro-gtk/retro-cairo-display.h b/retro-gtk/retro-cairo-display.h
new file mode 100644
index 0000000..1a54c28
--- /dev/null
+++ b/retro-gtk/retro-cairo-display.h
@@ -0,0 +1,41 @@
+// This file is part of retro-gtk. License: GPL-3.0+.
+
+#ifndef RETRO_CAIRO_DISPLAY_H
+#define RETRO_CAIRO_DISPLAY_H
+
+#if !defined(__RETRO_GTK_INSIDE__) && !defined(RETRO_GTK_COMPILATION)
+# error "Only <retro-gtk.h> can be included directly."
+#endif
+
+#include <gtk/gtk.h>
+#include "retro-video-filter.h"
+
+G_BEGIN_DECLS
+
+// FIXME Remove as soon as possible.
+typedef struct _RetroCore RetroCore;
+
+#define RETRO_TYPE_CAIRO_DISPLAY (retro_cairo_display_get_type())
+
+G_DECLARE_FINAL_TYPE (RetroCairoDisplay, retro_cairo_display, RETRO, CAIRO_DISPLAY, GtkDrawingArea)
+
+RetroCairoDisplay *retro_cairo_display_new (void);
+GdkPixbuf *retro_cairo_display_get_pixbuf (RetroCairoDisplay *self);
+void retro_cairo_display_set_pixbuf (RetroCairoDisplay *self,
+                                     GdkPixbuf         *pixbuf);
+void retro_cairo_display_set_core (RetroCairoDisplay *self,
+                                   RetroCore         *core);
+void retro_cairo_display_set_filter (RetroCairoDisplay *self,
+                                     RetroVideoFilter   filter);
+gboolean retro_cairo_display_get_coordinates_on_display (RetroCairoDisplay *self,
+                                                         gdouble            widget_x,
+                                                         gdouble            widget_y,
+                                                         gdouble           *display_x,
+                                                         gdouble           *display_y);
+void retro_cairo_display_show_video (RetroCairoDisplay *self);
+void retro_cairo_display_hide_video (RetroCairoDisplay *self);
+
+G_END_DECLS
+
+#endif /* RETRO_CAIRO_DISPLAY_H */
+
diff --git a/retro-gtk/retro-core-view.c b/retro-gtk/retro-core-view.c
index a8dc0f4..7256de4 100644
--- a/retro-gtk/retro-core-view.c
+++ b/retro-gtk/retro-core-view.c
@@ -2,6 +2,7 @@
 
 #include <linux/input-event-codes.h>
 #include "retro-gtk-internal.h"
+#include "retro-cairo-display.h"
 #include "retro-core-view.h"
 #include "retro-core-view-input-device.h"
 #include "retro-joypad-id.h"