EomScrollView: Switch to GdkRGBA for background and transparent colors

This allows passing the colors more or less directly to cairo
without having to convert it from and to the GdkColor format.

taken from:
https://git.gnome.org/browse/eog/commit/?id=823a4cd

2 files changed, 65 insertions, 79 deletions

diff --git a/src/eom-scroll-view.c b/src/eom-scroll-view.c
index 4ab1a11..0a321d0 100644
--- a/src/eom-scroll-view.c
+++ b/src/eom-scroll-view.c
@@ -31,11 +31,11 @@
 #define MIN_ZOOM_FACTOR 0.02
 
 #define CHECK_MEDIUM 8
-#define CHECK_BLACK 0x00000000
-#define CHECK_DARK 0x00555555
-#define CHECK_GRAY 0x00808080
-#define CHECK_LIGHT 0x00cccccc
-#define CHECK_WHITE 0x00ffffff
+#define CHECK_BLACK "#000000"
+#define CHECK_DARK "#555555"
+#define CHECK_GRAY "#808080"
+#define CHECK_LIGHT "#cccccc"
+#define CHECK_WHITE "#ffffff"
 
 /* Default increment for zooming.  The current zoom factor is multiplied or
  * divided by this amount on every zooming step.  For consistency, you should
@@ -134,14 +134,14 @@ struct _EomScrollViewPrivate {
 
 	/* how to indicate transparency in images */
 	EomTransparencyStyle transp_style;
-	guint32 transp_color;
+	GdkRGBA transp_color;
 
 	/* the type of the cursor we are currently showing */
 	EomScrollViewCursor cursor;
 
 	gboolean  use_bg_color;
-	GdkColor *background_color;
-	GdkColor *override_bg_color;
+	GdkRGBA *background_color;
+	GdkRGBA *override_bg_color;
 
 	cairo_surface_t *background_surface;
 };
@@ -160,6 +160,8 @@ static void view_on_drag_data_get_cb (GtkWidget *widget,
 #define EOM_SCROLL_VIEW_GET_PRIVATE(object) \
 	(G_TYPE_INSTANCE_GET_PRIVATE ((object), EOM_TYPE_SCROLL_VIEW, EomScrollViewPrivate))
 
+static gboolean _eom_gdk_rgba_equal0 (const GdkRGBA *a, const GdkRGBA *b);
+
 G_DEFINE_TYPE (EomScrollView, eom_scroll_view, GTK_TYPE_GRID)
 
 /*===================================
@@ -494,7 +496,7 @@ is_image_movable (EomScrollView *view)
   ---------------------------------*/
 
 static void
-get_transparency_params (EomScrollView *view, int *size, guint32 *color1, guint32 *color2)
+get_transparency_params (EomScrollView *view, int *size, GdkRGBA *color1, GdkRGBA *color2)
 {
 	EomScrollViewPrivate *priv;
 
@@ -503,16 +505,15 @@ get_transparency_params (EomScrollView *view, int *size, guint32 *color1, guint3
 	/* Compute transparency parameters */
 	switch (priv->transp_style) {
 	case EOM_TRANSP_BACKGROUND: {
-		GdkColor color = gtk_widget_get_style (GTK_WIDGET (priv->display))->bg[GTK_STATE_NORMAL];
-
-		*color1 = *color2 = (((color.red & 0xff00) << 8)
-				       | (color.green & 0xff00)
-				       | ((color.blue & 0xff00) >> 8));
-		break; }
+		/* Simply return fully transparent color */
+		color1->red = color1->green = color1->blue = color1->alpha = 0.0;
+		color2->red = color2->green = color2->blue = color2->alpha = 0.0;
+		break;
+	}
 
 	case EOM_TRANSP_CHECKED:
-		*color1 = CHECK_GRAY;
-		*color2 = CHECK_LIGHT;
+		g_warn_if_fail (gdk_rgba_parse (color1, CHECK_GRAY));
+		g_warn_if_fail (gdk_rgba_parse (color2, CHECK_LIGHT));
 		break;
 
 	case EOM_TRANSP_COLOR:
@@ -530,29 +531,25 @@ static cairo_surface_t *
 create_background_surface (EomScrollView *view)
 {
 	int check_size;
-	guint32 check_1 = 0;
-	guint32 check_2 = 0;
+	GdkRGBA check_1;
+	GdkRGBA check_2;
 	cairo_surface_t *surface;
 
 	get_transparency_params (view, &check_size, &check_1, &check_2);
 	surface = gdk_window_create_similar_surface (gtk_widget_get_window (view->priv->display),
-						     CAIRO_CONTENT_COLOR,
+						     CAIRO_CONTENT_COLOR_ALPHA,
 						     check_size * 2, check_size * 2);
 	cairo_t* cr = cairo_create (surface);
-	cairo_set_source_rgba (cr,
-			       ((check_1 & 0xff0000) >> 16) / 255.,
-			       ((check_1 & 0x00ff00) >> 8)  / 255.,
-			       (check_1 & 0x0000ff)         / 255.,
-			       1.);
+
+	/* Use source operator to make fully transparent work */
+	cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
+
+	gdk_cairo_set_source_rgba(cr, &check_1);
 	cairo_rectangle (cr, 0, 0, check_size, check_size);
 	cairo_rectangle (cr, check_size, check_size, check_size, check_size);
 	cairo_fill (cr);
 
-	cairo_set_source_rgba (cr,
-			       ((check_2 & 0xff0000) >> 16) / 255.,
-			       ((check_2 & 0x00ff00) >> 8)  / 255.,
-			       (check_2 & 0x0000ff)         / 255.,
-			       1.);
+	gdk_cairo_set_source_rgba(cr, &check_2);
 	cairo_rectangle (cr, 0, check_size, check_size, check_size);
 	cairo_rectangle (cr, check_size, 0, check_size, check_size);
 	cairo_fill (cr);
@@ -1448,25 +1445,16 @@ _transp_background_changed (EomScrollView *view)
 }
 
 void
-eom_scroll_view_set_transparency_color (EomScrollView *view, GdkColor *color)
+eom_scroll_view_set_transparency_color (EomScrollView *view, GdkRGBA *color)
 {
-	guint32 col = 0;
-	guint32 red, green, blue;
 	EomScrollViewPrivate *priv;
 
 	g_return_if_fail (EOM_IS_SCROLL_VIEW (view));
 
 	priv = view->priv;
 
-	if (color != NULL) {
-		red = (color->red >> 8) << 16;
-		green = (color->green >> 8) << 8;
-		blue = (color->blue >> 8);
-		col = red + green + blue;
-	}
-
-	if (priv->transp_style != col) {
-		priv->transp_color = col;
+	if (!_eom_gdk_rgba_equal0 (&priv->transp_color, color)) {
+		priv->transp_color = *color;
 		if (priv->transp_style == EOM_TRANSP_COLOR)
 		    _transp_background_changed (view);
 
@@ -1689,15 +1677,15 @@ eom_scroll_view_scrollbars_visible (EomScrollView *view)
   ---------------------------------*/
 
 static gboolean
-sv_string_to_color_mapping (GValue   *value,
+sv_string_to_rgba_mapping (GValue   *value,
 			    GVariant *variant,
 			    gpointer  user_data)
 {
-	GdkColor color;
+	GdkRGBA color;
 
 	g_return_val_if_fail (g_variant_is_of_type (variant, G_VARIANT_TYPE_STRING), FALSE);
 
-	if (gdk_color_parse (g_variant_get_string (variant, NULL), &color)) {
+	if (gdk_rgba_parse (&color, g_variant_get_string (variant, NULL))) {
 		g_value_set_boxed (value, &color);
 		return TRUE;
 	}
@@ -1706,22 +1694,19 @@ sv_string_to_color_mapping (GValue   *value,
 }
 
 static GVariant*
-sv_color_to_string_mapping (const GValue       *value,
+sv_rgba_to_string_mapping (const GValue       *value,
 			    const GVariantType *expected_type,
 			    gpointer            user_data)
 {
 	GVariant *variant = NULL;
-	GdkColor *color;
+	GdkRGBA *color;
 	gchar *hex_val;
 
-	g_return_val_if_fail (G_VALUE_TYPE (value) == GDK_TYPE_COLOR, NULL);
+	g_return_val_if_fail (G_VALUE_TYPE (value) == GDK_TYPE_RGBA, NULL);
 	g_return_val_if_fail (g_variant_type_equal (expected_type, G_VARIANT_TYPE_STRING), NULL);
 
 	color = g_value_get_boxed (value);
-	hex_val = g_strdup_printf ("#%02X%02X%02X",
-				   color->red / 256,
-				   color->green / 256,
-				   color->blue / 256);
+	hex_val = gdk_rgba_to_string(color);
 	variant = g_variant_new_string (hex_val);
 	g_free (hex_val);
 
@@ -1749,7 +1734,7 @@ eom_scroll_view_init (EomScrollView *view)
 	priv->pixbuf = NULL;
 	priv->surface = NULL;
 	priv->transp_style = EOM_TRANSP_BACKGROUND;
-	priv->transp_color = 0;
+	g_warn_if_fail (gdk_rgba_parse(&priv->transp_color, CHECK_BLACK));
 	priv->cursor = EOM_SCROLL_VIEW_CURSOR_NORMAL;
 	priv->menu = NULL;
 	priv->background_color = NULL;
@@ -1825,8 +1810,8 @@ eom_scroll_view_init (EomScrollView *view)
 	g_settings_bind_with_mapping (settings, EOM_CONF_VIEW_BACKGROUND_COLOR,
 				      view, "background-color",
 				      G_SETTINGS_BIND_DEFAULT,
-				      sv_string_to_color_mapping,
-				      sv_color_to_string_mapping, NULL, NULL);
+				      sv_string_to_rgba_mapping,
+				      sv_rgba_to_string_mapping, NULL, NULL);
 	g_settings_bind (settings, EOM_CONF_VIEW_EXTRAPOLATE, view,
 			 "antialiasing-in", G_SETTINGS_BIND_GET);
 	g_settings_bind (settings, EOM_CONF_VIEW_INTERPOLATE, view,
@@ -1834,8 +1819,8 @@ eom_scroll_view_init (EomScrollView *view)
 	g_settings_bind_with_mapping (settings, EOM_CONF_VIEW_TRANS_COLOR,
 				      view, "transparency-color",
 				      G_SETTINGS_BIND_GET,
-				      sv_string_to_color_mapping,
-				      sv_color_to_string_mapping, NULL, NULL);
+				      sv_string_to_rgba_mapping,
+				      sv_rgba_to_string_mapping, NULL, NULL);
 	g_settings_bind (settings, EOM_CONF_VIEW_TRANSPARENCY, view,
 			 "transparency-style", G_SETTINGS_BIND_GET);
 
@@ -1862,12 +1847,12 @@ eom_scroll_view_dispose (GObject *object)
 	}
 
 	if (priv->background_color != NULL) {
-		gdk_color_free (priv->background_color);
+		gdk_rgba_free (priv->background_color);
 		priv->background_color = NULL;
 	}
 
 	if (priv->override_bg_color != NULL) {
-		gdk_color_free (priv->override_bg_color);
+		gdk_rgba_free (priv->override_bg_color);
 		priv->override_bg_color = NULL;
 	}
 
@@ -1949,7 +1934,7 @@ eom_scroll_view_set_property (GObject *object, guint property_id,
 		break;
 	case PROP_BACKGROUND_COLOR:
 	{
-		const GdkColor *color = g_value_get_boxed (value);
+		const GdkRGBA *color = g_value_get_boxed (value);
 		eom_scroll_view_set_background_color (view, color);
 		break;
 	}
@@ -2004,7 +1989,7 @@ eom_scroll_view_class_init (EomScrollViewClass *klass)
 	g_object_class_install_property (
 		gobject_class, PROP_BACKGROUND_COLOR,
 		g_param_spec_boxed ("background-color", NULL, NULL,
-				    GDK_TYPE_COLOR,
+				    GDK_TYPE_RGBA,
 				    G_PARAM_READWRITE | G_PARAM_STATIC_NAME));
 
 	g_object_class_install_property (
@@ -2044,7 +2029,7 @@ eom_scroll_view_class_init (EomScrollViewClass *klass)
 	g_object_class_install_property (
 		gobject_class, PROP_TRANSP_COLOR,
 		g_param_spec_boxed ("transparency-color", NULL, NULL,
-				    GDK_TYPE_COLOR,
+				    GDK_TYPE_RGBA,
 				    G_PARAM_WRITABLE | G_PARAM_STATIC_NAME));
 
 	/**
@@ -2192,26 +2177,26 @@ eom_scroll_view_set_popup (EomScrollView *view,
 }
 
 static gboolean
-_eom_gdk_color_equal0 (const GdkColor *a, const GdkColor *b)
+_eom_gdk_rgba_equal0 (const GdkRGBA *a, const GdkRGBA *b)
 {
 	if (a == NULL || b == NULL)
 		return (a == b);
 
-	return gdk_color_equal (a, b);
+	return gdk_rgba_equal (a, b);
 }
 
 static gboolean
-_eom_replace_gdk_color (GdkColor **dest, const GdkColor *new)
+_eom_replace_gdk_rgba (GdkRGBA **dest, const GdkRGBA *src)
 {
-	GdkColor *old = *dest;
+	GdkRGBA *old = *dest;
 
-	if (_eom_gdk_color_equal0 (old, new))
+	if (_eom_gdk_rgba_equal0 (old, src))
 		return FALSE;
 
 	if (old != NULL)
-		gdk_color_free (old);
+		gdk_rgba_free (old);
 
-	*dest = (new) ? gdk_color_copy (new) : NULL;
+	*dest = (src) ? gdk_rgba_copy (src) : NULL;
 
 	return TRUE;
 }
@@ -2219,7 +2204,7 @@ _eom_replace_gdk_color (GdkColor **dest, const GdkColor *new)
 static void
 _eom_scroll_view_update_bg_color (EomScrollView *view)
 {
-	const GdkColor *selected;
+	const GdkRGBA *selected;
 	EomScrollViewPrivate *priv = view->priv;
 
 	if (!priv->use_bg_color)
@@ -2237,28 +2222,29 @@ _eom_scroll_view_update_bg_color (EomScrollView *view)
 		priv->background_surface = NULL;
 	}
 
-	gtk_widget_modify_bg (GTK_WIDGET (priv->display),
+	/*gtk_widget_modify_bg (GTK_WIDGET (priv->display),
 			      GTK_STATE_NORMAL,
-			      selected);
+			      selected);*/
+	gtk_widget_override_background_color(GTK_WIDGET (priv->display), GTK_STATE_FLAG_NORMAL, selected);
 }
 
 void
 eom_scroll_view_set_background_color (EomScrollView *view,
-				      const GdkColor *color)
+				      const GdkRGBA *color)
 {
 	g_return_if_fail (EOM_IS_SCROLL_VIEW (view));
 
-	if (_eom_replace_gdk_color (&view->priv->background_color, color))
+	if (_eom_replace_gdk_rgba (&view->priv->background_color, color))
 		_eom_scroll_view_update_bg_color (view);
 }
 
 void
 eom_scroll_view_override_bg_color (EomScrollView *view,
-				   const GdkColor *color)
+				   const GdkRGBA *color)
 {
 	g_return_if_fail (EOM_IS_SCROLL_VIEW (view));
 
-	if (_eom_replace_gdk_color (&view->priv->override_bg_color, color))
+	if (_eom_replace_gdk_rgba (&view->priv->override_bg_color, color))
 		_eom_scroll_view_update_bg_color (view);
 }
 
diff --git a/src/eom-scroll-view.h b/src/eom-scroll-view.h
index d618fff..69a57a4 100644
--- a/src/eom-scroll-view.h
+++ b/src/eom-scroll-view.h
@@ -47,14 +47,14 @@ void     eom_scroll_view_set_zoom_upscale (EomScrollView *view, gboolean upscale
 void     eom_scroll_view_set_zoom_multiplier (EomScrollView *view, gdouble multiplier);
 void     eom_scroll_view_set_antialiasing_in (EomScrollView *view, gboolean state);
 void     eom_scroll_view_set_antialiasing_out (EomScrollView *view, gboolean state);
-void     eom_scroll_view_set_transparency_color (EomScrollView *view, GdkColor *color);
+void     eom_scroll_view_set_transparency_color (EomScrollView *view, GdkRGBA *color);
 void     eom_scroll_view_set_transparency (EomScrollView *view, EomTransparencyStyle style);
 gboolean eom_scroll_view_scrollbars_visible (EomScrollView *view);
 void	 eom_scroll_view_set_popup (EomScrollView *view, GtkMenu *menu);
 void	 eom_scroll_view_set_background_color (EomScrollView *view,
-					       const GdkColor *color);
+					       const GdkRGBA *color);
 void	 eom_scroll_view_override_bg_color (EomScrollView *view,
-					    const GdkColor *color);
+					    const GdkRGBA *color);
 void     eom_scroll_view_set_use_bg_color (EomScrollView *view, gboolean use);
 /* zoom api */
 void     eom_scroll_view_zoom_in          (EomScrollView *view, gboolean smooth);