[gtk: 19/23] color chooser: Port checkered pattern drawing from cairo

[Timm Bäder <baedert src gnome org>]

commit 6f1cade817337004c458c8b12a7b50f1e73c4147
Author: Timm Bäder <mail baedert org>
Date:   Sun Aug 11 08:34:43 2019 +0200

    color chooser: Port checkered pattern drawing from cairo

 gtk/gtkcolorchooser.c        | 33 +++++++++++++++------------------
 gtk/gtkcolorchooserprivate.h |  5 ++++-
 gtk/gtkcolorscale.c          | 23 ++---------------------
 gtk/gtkcolorswatch.c         | 35 +++++------------------------------
 4 files changed, 26 insertions(+), 70 deletions(-)
---
diff --git a/gtk/gtkcolorchooser.c b/gtk/gtkcolorchooser.c
index eb63aac76c..f5389fa806 100644
--- a/gtk/gtkcolorchooser.c
+++ b/gtk/gtkcolorchooser.c
@@ -23,6 +23,8 @@
 #include "gtkintl.h"
 #include "gtktypebuiltins.h"
 #include "gtkprivate.h"
+#include "gtksnapshot.h"
+#include "gdk/gdkrgbaprivate.h"
 
 /**
  * SECTION:gtkcolorchooser
@@ -222,23 +224,18 @@ gtk_color_chooser_add_palette (GtkColorChooser *chooser,
     GTK_COLOR_CHOOSER_GET_IFACE (chooser)->add_palette (chooser, orientation, colors_per_line, n_colors, 
colors);
 }
 
-cairo_pattern_t *
-_gtk_color_chooser_get_checkered_pattern (void)
+void
+_gtk_color_chooser_snapshot_checkered_pattern (GtkSnapshot *snapshot,
+                                               int          width,
+                                               int          height)
 {
-  /* need to respect pixman's stride being a multiple of 4 */
-  static unsigned char data[8] = { 0xFF, 0x00, 0x00, 0x00,
-                                   0x00, 0xFF, 0x00, 0x00 };
-  static cairo_surface_t *checkered = NULL;
-  cairo_pattern_t *pattern;
-
-  if (checkered == NULL)
-    checkered = cairo_image_surface_create_for_data (data,
-                                                     CAIRO_FORMAT_A8,
-                                                     2, 2, 4);
-
-  pattern = cairo_pattern_create_for_surface (checkered);
-  cairo_pattern_set_extend (pattern, CAIRO_EXTEND_REPEAT);
-  cairo_pattern_set_filter (pattern, CAIRO_FILTER_NEAREST);
-
-  return pattern;
+  const GdkRGBA color1 = GDK_RGBA("A8A8A8");
+  const GdkRGBA color2 = GDK_RGBA("545445");
+
+  gtk_snapshot_push_repeat (snapshot, &GRAPHENE_RECT_INIT (0, 0, width, height), NULL);
+  gtk_snapshot_append_color (snapshot, &color1, &GRAPHENE_RECT_INIT (0,  0,  10, 10));
+  gtk_snapshot_append_color (snapshot, &color2, &GRAPHENE_RECT_INIT (10, 0,  10, 10));
+  gtk_snapshot_append_color (snapshot, &color2, &GRAPHENE_RECT_INIT (0,  10, 10, 10));
+  gtk_snapshot_append_color (snapshot, &color1, &GRAPHENE_RECT_INIT (10, 10, 10, 10));
+  gtk_snapshot_pop (snapshot);
 }
diff --git a/gtk/gtkcolorchooserprivate.h b/gtk/gtkcolorchooserprivate.h
index 1a5c34d271..c4c1c935f9 100644
--- a/gtk/gtkcolorchooserprivate.h
+++ b/gtk/gtkcolorchooserprivate.h
@@ -25,7 +25,10 @@ G_BEGIN_DECLS
 void _gtk_color_chooser_color_activated (GtkColorChooser *chooser,
                                          const GdkRGBA   *color);
 
-cairo_pattern_t * _gtk_color_chooser_get_checkered_pattern (void);
+void _gtk_color_chooser_snapshot_checkered_pattern (GtkSnapshot *snapshot,
+                                                    int          width,
+                                                    int          height);
+
 
 G_END_DECLS
 
diff --git a/gtk/gtkcolorscale.c b/gtk/gtkcolorscale.c
index c5b7d3046a..0ee32118db 100644
--- a/gtk/gtkcolorscale.c
+++ b/gtk/gtkcolorscale.c
@@ -120,17 +120,12 @@ gtk_color_scale_snapshot_trough (GtkColorScale  *scale,
     }
   else if (priv->type == GTK_COLOR_SCALE_ALPHA)
     {
-      cairo_t *cr;
       graphene_point_t start, end;
-
-      cr = gtk_snapshot_append_cairo (snapshot,
-                                      &GRAPHENE_RECT_INIT(0, 0, width, height));
+      const GdkRGBA *color;
 
       if (gtk_orientable_get_orientation (GTK_ORIENTABLE (widget)) == GTK_ORIENTATION_HORIZONTAL &&
           gtk_widget_get_direction (widget) == GTK_TEXT_DIR_RTL)
         {
-          cairo_translate (cr, width, 0);
-          cairo_scale (cr, -1, 1);
           graphene_point_init (&start, width, 0);
           graphene_point_init (&end, 0, 0);
         }
@@ -140,21 +135,7 @@ gtk_color_scale_snapshot_trough (GtkColorScale  *scale,
           graphene_point_init (&end, width, 0);
         }
 
-      cairo_pattern_t *pattern;
-      cairo_matrix_t matrix;
-      GdkRGBA *color;
-
-      cairo_set_source_rgb (cr, 0.33, 0.33, 0.33);
-      cairo_paint (cr);
-      cairo_set_source_rgb (cr, 0.66, 0.66, 0.66);
-
-      pattern = _gtk_color_chooser_get_checkered_pattern ();
-      cairo_matrix_init_scale (&matrix, 0.125, 0.125);
-      cairo_pattern_set_matrix (pattern, &matrix);
-      cairo_mask (cr, pattern);
-      cairo_pattern_destroy (pattern);
-
-      cairo_destroy (cr);
+      _gtk_color_chooser_snapshot_checkered_pattern (snapshot, width, height);
 
       color = &priv->color;
 
diff --git a/gtk/gtkcolorswatch.c b/gtk/gtkcolorswatch.c
index d17093fe9a..b44487774a 100644
--- a/gtk/gtkcolorswatch.c
+++ b/gtk/gtkcolorswatch.c
@@ -85,40 +85,18 @@ swatch_snapshot (GtkWidget   *widget,
 {
   GtkColorSwatch *swatch = GTK_COLOR_SWATCH (widget);
   GtkColorSwatchPrivate *priv = gtk_color_swatch_get_instance_private (swatch);
+  const int width = gtk_widget_get_width (widget);
+  const int height = gtk_widget_get_height (widget);
 
   if (priv->has_color)
     {
-      cairo_pattern_t *pattern;
-      cairo_matrix_t matrix;
-
       if (priv->use_alpha && !gdk_rgba_is_opaque (&priv->color))
         {
-          cairo_t *cr;
-
-          cr = gtk_snapshot_append_cairo (snapshot,
-                                          &GRAPHENE_RECT_INIT (
-                                              0, 0,
-                                              gtk_widget_get_width (widget),
-                                              gtk_widget_get_height (widget)));
-          cairo_set_source_rgb (cr, 0.33, 0.33, 0.33);
-          cairo_paint (cr);
-
-          pattern = _gtk_color_chooser_get_checkered_pattern ();
-          cairo_matrix_init_scale (&matrix, 0.125, 0.125);
-          cairo_pattern_set_matrix (pattern, &matrix);
-
-          cairo_set_source_rgb (cr, 0.66, 0.66, 0.66);
-          cairo_mask (cr, pattern);
-          cairo_pattern_destroy (pattern);
-
-          cairo_destroy (cr);
+          _gtk_color_chooser_snapshot_checkered_pattern (snapshot, width, height);
 
           gtk_snapshot_append_color (snapshot,
                                      &priv->color,
-                                     &GRAPHENE_RECT_INIT (
-                                         0, 0,
-                                         gtk_widget_get_width (widget),
-                                         gtk_widget_get_height (widget)));
+                                     &GRAPHENE_RECT_INIT (0, 0, width, height));
         }
       else
         {
@@ -128,10 +106,7 @@ swatch_snapshot (GtkWidget   *widget,
 
           gtk_snapshot_append_color (snapshot,
                                      &color,
-                                     &GRAPHENE_RECT_INIT (
-                                         0, 0,
-                                         gtk_widget_get_width (widget),
-                                         gtk_widget_get_height (widget)));
+                                     &GRAPHENE_RECT_INIT (0, 0, width, height));
         }
     }