Add a way to load recolored icons in CSS

This can come in handy to load images that are not in an icon theme,
but still benefit from symbolic recoloring.

https://bugzilla.gnome.org/show_bug.cgi?id=760536

1 files changed, 215 insertions, 0 deletions

diff --git a/gtk/gtkcssimagerecolor.c b/gtk/gtkcssimagerecolor.c
new file mode 100644
index 0000000000..0d6948a175
--- /dev/null
+++ b/gtk/gtkcssimagerecolor.c
@@ -0,0 +1,215 @@
+/*
+ * Copyright © 2016 Red Hat Inc.
+ *
+ * This library 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 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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 this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Matthias Clasen <mclasen@redhat.com>
+ */
+
+#include "config.h"
+
+#include "gtkcssimagerecolorprivate.h"
+#include "gtkcssimageurlprivate.h"
+#include "gtkcssimagesurfaceprivate.h"
+#include "gtkcsspalettevalueprivate.h"
+#include "gtkcssrgbavalueprivate.h"
+#include "gtkiconthemeprivate.h"
+
+#include "gtkstyleproviderprivate.h"
+
+G_DEFINE_TYPE (GtkCssImageRecolor, _gtk_css_image_recolor, GTK_TYPE_CSS_IMAGE_URL)
+
+static void
+gtk_css_image_recolor_print (GtkCssImage *image,
+                             GString     *string)
+{
+  GtkCssImageUrl *url = GTK_CSS_IMAGE_URL (image);
+  GtkCssImageRecolor *recolor = GTK_CSS_IMAGE_RECOLOR (image);
+  char *uri;
+
+  g_string_append (string, "-gtk-recolor(url(");
+  uri = g_file_get_uri (url->file);
+  g_string_append (string, uri);
+  g_free (uri);
+  g_string_append (string, ")");
+  if (recolor->palette)
+    {
+      g_string_append (string, ",");
+      _gtk_css_value_print (recolor->palette, string);
+    }
+  g_string_append (string, ")");
+}
+
+static void
+gtk_css_image_recolor_dispose (GObject *object)
+{
+  GtkCssImageRecolor *recolor = GTK_CSS_IMAGE_RECOLOR (object);
+
+  if (recolor->palette)
+    {
+      _gtk_css_value_unref (recolor->palette);
+      recolor->palette = NULL;
+    }
+
+  G_OBJECT_CLASS (_gtk_css_image_recolor_parent_class)->dispose (object);
+}
+
+static void
+lookup_symbolic_colors (GtkCssStyle *style,
+                        GtkCssValue *palette,
+                        GdkRGBA     *color_out,
+                        GdkRGBA     *success_out,
+                        GdkRGBA     *warning_out,
+                        GdkRGBA     *error_out)
+{
+  GtkCssValue *color;
+  const GdkRGBA *lookup;
+
+  color = gtk_css_style_get_value (style, GTK_CSS_PROPERTY_COLOR);
+  *color_out = *_gtk_css_rgba_value_get_rgba (color);
+
+  lookup = gtk_css_palette_value_get_color (palette, "success");
+  if (lookup)
+    *success_out = *lookup;
+  else
+    *success_out = *color_out;
+
+  lookup = gtk_css_palette_value_get_color (palette, "warning");
+  if (lookup)
+    *warning_out = *lookup;
+  else
+    *warning_out = *color_out;
+
+  lookup = gtk_css_palette_value_get_color (palette, "error");
+  if (lookup)
+    *error_out = *lookup;
+  else
+    *error_out = *color_out;
+}
+
+static GtkCssImage *
+gtk_css_image_recolor_load (GtkCssImageRecolor *recolor,
+                            GtkCssStyle        *style,
+                            GtkCssValue        *palette)
+{
+  GtkCssImageUrl *url = GTK_CSS_IMAGE_URL (recolor);
+  GtkIconInfo *info;
+  GdkRGBA fg, success, warning, error;
+  GdkPixbuf *pixbuf;
+  GtkCssImage *image;
+
+  lookup_symbolic_colors (style, palette, &fg, &success, &warning, &error);
+
+  info = gtk_icon_info_new_for_file (url->file, 0, 1);
+  pixbuf = gtk_icon_info_load_symbolic (info, &fg, &success, &warning, &error, NULL, NULL);
+  g_object_unref (info);
+
+  if (pixbuf == NULL)
+    {
+      g_warning ("Failed to load icon");
+      return NULL;
+    }
+
+  image = _gtk_css_image_surface_new_for_pixbuf (pixbuf);
+  g_object_unref (pixbuf);
+
+  return image;
+}
+
+static GtkCssImage *
+gtk_css_image_recolor_compute (GtkCssImage             *image,
+                               guint                    property_id,
+                               GtkStyleProviderPrivate *provider,
+                               GtkCssStyle             *style,
+                               GtkCssStyle             *parent_style)
+{
+  GtkCssImageRecolor *recolor = GTK_CSS_IMAGE_RECOLOR (image);
+  GtkCssValue *palette;
+  GtkCssImage *img;
+
+  if (recolor->palette)
+    palette = _gtk_css_value_compute (recolor->palette, property_id, provider, style, parent_style);
+  else
+    palette = gtk_css_style_get_value (style, GTK_CSS_PROPERTY_ICON_PALETTE);
+
+  img = gtk_css_image_recolor_load (recolor, style, palette);
+
+  _gtk_css_value_unref (palette);
+
+  return img;
+}
+
+static gboolean
+gtk_css_image_recolor_parse (GtkCssImage  *image,
+                             GtkCssParser *parser)
+{
+  GtkCssImageUrl *url = GTK_CSS_IMAGE_URL (image);
+  GtkCssImageRecolor *recolor = GTK_CSS_IMAGE_RECOLOR (image);
+
+  if (!_gtk_css_parser_try (parser, "-gtk-recolor", TRUE))
+    {
+      _gtk_css_parser_error (parser, "'-gtk-recolor'");
+      return FALSE;
+    }
+
+  if (!_gtk_css_parser_try (parser, "(", TRUE))
+    {
+      _gtk_css_parser_error (parser, "Expected '(' after '-gtk-recolor'");
+      return FALSE;
+    }
+
+  url->file = _gtk_css_parser_read_url (parser);
+  if (url->file == NULL)
+    {
+      _gtk_css_parser_error (parser, "Expected a url here");
+      return FALSE;
+    }
+
+  if ( _gtk_css_parser_try (parser, ",", TRUE))
+    {
+      recolor->palette = gtk_css_palette_value_parse (parser);
+      if (recolor->palette == NULL)
+        {
+          _gtk_css_parser_error (parser, "A palette is required here");
+          return FALSE;
+        }
+    }
+
+  if (!_gtk_css_parser_try (parser, ")", TRUE))
+    {
+      _gtk_css_parser_error (parser,
+                             "Expected ')' at end of '-gtk-recolor'");
+      return FALSE;
+    }
+
+  return TRUE;
+}
+
+static void
+_gtk_css_image_recolor_class_init (GtkCssImageRecolorClass *klass)
+{
+  GtkCssImageClass *image_class = GTK_CSS_IMAGE_CLASS (klass);
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  image_class->parse = gtk_css_image_recolor_parse;
+  image_class->compute = gtk_css_image_recolor_compute;
+  image_class->print = gtk_css_image_recolor_print;
+
+  object_class->dispose = gtk_css_image_recolor_dispose;
+}
+
+static void
+_gtk_css_image_recolor_init (GtkCssImageRecolor *image_recolor)
+{
+}