[gtk+/wip/matthiasc/fancy-overlay] overlay: Change the effect to a blur

[Matthias Clasen <matthiasc src gnome org>]

commit 5c88157a0679fd196d49db9c4dab6982773a4c9a
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Sep 2 23:53:34 2017 -0400

    overlay: Change the effect to a blur
    
    And rename the child property blur, and make it a double,
    so we can specify the blur radius.

 gtk/gtkoverlay.c    |   53 +++++++++++++++++---------------------------------
 tests/testoverlay.c |    2 +-
 2 files changed, 19 insertions(+), 36 deletions(-)
---
diff --git a/gtk/gtkoverlay.c b/gtk/gtkoverlay.c
index e7ed1a1..b96e5f2 100644
--- a/gtk/gtkoverlay.c
+++ b/gtk/gtkoverlay.c
@@ -66,7 +66,7 @@ struct _GtkOverlayChild
 {
   GtkWidget *widget;
   gboolean pass_through;
-  gboolean effect;
+  double blur;
 };
 
 enum {
@@ -78,7 +78,7 @@ enum
 {
   CHILD_PROP_0,
   CHILD_PROP_PASS_THROUGH,
-  CHILD_PROP_EFFECT,
+  CHILD_PROP_BLUR,
   CHILD_PROP_INDEX
 };
 
@@ -542,13 +542,13 @@ gtk_overlay_set_child_property (GtkContainer *container,
            }
        }
       break;
-    case CHILD_PROP_EFFECT:
+    case CHILD_PROP_BLUR:
       if (child_info)
        {
-         if (g_value_get_boolean (value) != child_info->effect)
+         if (g_value_get_double (value) != child_info->blur)
            {
-             child_info->effect = g_value_get_boolean (value);
-             gtk_container_child_notify (container, child, "effect");
+             child_info->blur = g_value_get_double (value);
+             gtk_container_child_notify (container, child, "blur");
               gtk_widget_queue_draw (GTK_WIDGET (overlay));
            }
        }
@@ -599,11 +599,11 @@ gtk_overlay_get_child_property (GtkContainer *container,
       else
        g_value_set_boolean (value, FALSE);
       break;
-    case CHILD_PROP_EFFECT:
+    case CHILD_PROP_BLUR:
       if (child_info)
-       g_value_set_boolean (value, child_info->effect);
+       g_value_set_double (value, child_info->blur);
       else
-       g_value_set_boolean (value, FALSE);
+       g_value_set_double (value, 0);
       break;
     case CHILD_PROP_INDEX:
       g_value_set_int (value, g_slist_index (priv->children, child_info));
@@ -621,10 +621,7 @@ gtk_overlay_snapshot (GtkWidget   *widget,
   GtkWidget *main_widget;
   GtkWidget *child;
   graphene_rect_t bounds;
-  gboolean effect;
-  double value;
-  graphene_matrix_t matrix;
-  graphene_vec4_t offset;
+  double blur = 0;
   GtkAllocation alloc;
   GtkAllocation effect_alloc;
   cairo_region_t *clip;
@@ -634,15 +631,15 @@ gtk_overlay_snapshot (GtkWidget   *widget,
        child != NULL;
        child = _gtk_widget_get_next_sibling (child))
     {
-      gtk_container_child_get (GTK_CONTAINER (widget), child, "effect", &effect, NULL);
-      if (effect)
+      gtk_container_child_get (GTK_CONTAINER (widget), child, "blur", &blur, NULL);
+      if (blur > 0)
         {
           gtk_widget_get_allocation (child, &effect_alloc);
           break;
         }
     }
 
-  if (!effect)
+  if (blur == 0)
     {
       GTK_WIDGET_CLASS (gtk_overlay_parent_class)->snapshot (widget, snapshot);
       return;
@@ -650,24 +647,10 @@ gtk_overlay_snapshot (GtkWidget   *widget,
 
   main_widget = gtk_bin_get_child (GTK_BIN (widget));
 
-  /* hardcode grayscale for now */
-#define R 0.2126
-#define G 0.7152
-#define B 0.0722
-
-  value = 1.0;
-  graphene_matrix_init_from_float (&matrix, (float[16]) {
-                                           1.0 - (1.0 - R) * value, R * value, R * value, 0.0,
-                                           G * value, 1.0 - (1.0 - G) * value, G * value, 0.0,
-                                           B * value, B * value, 1.0 - (1.0 - B) * value, 0.0,
-                                           0.0, 0.0, 0.0, 1.0
-                                       });
-  graphene_vec4_init (&offset, 0.0, 0.0, 0.0, 0.0);
-
   gtk_widget_get_allocation (widget, &alloc);
   graphene_rect_init (&bounds, effect_alloc.x, effect_alloc.y, effect_alloc.width, effect_alloc.height);
   gtk_snapshot_push_clip (snapshot, &bounds, "Overlay Effect Clip");
-  gtk_snapshot_push_color_matrix (snapshot, &matrix, &offset, "Overlay Effect");
+  gtk_snapshot_push_blur (snapshot, blur, "Overlay Effect");
 
   gtk_widget_snapshot_child (widget, main_widget, snapshot);
 
@@ -730,10 +713,10 @@ gtk_overlay_class_init (GtkOverlayClass *klass)
                             FALSE,
                             GTK_PARAM_READWRITE));
 
-  gtk_container_class_install_child_property (container_class, CHILD_PROP_EFFECT,
-      g_param_spec_boolean ("effect", NULL, NULL,
-                            FALSE,
-                            GTK_PARAM_READWRITE));
+  gtk_container_class_install_child_property (container_class, CHILD_PROP_BLUR,
+      g_param_spec_double ("blur", NULL, NULL,
+                           0, 100, 0,
+                           GTK_PARAM_READWRITE));
   /**
    * GtkOverlay:index:
    *
diff --git a/tests/testoverlay.c b/tests/testoverlay.c
index 7b0ae47..041c22e 100644
--- a/tests/testoverlay.c
+++ b/tests/testoverlay.c
@@ -561,7 +561,7 @@ test_effect (void)
   gtk_widget_set_valign (button, GTK_ALIGN_START);
 
   gtk_overlay_add_overlay (GTK_OVERLAY (overlay), button);
-  gtk_container_child_set (GTK_CONTAINER (overlay), button, "effect", TRUE, NULL);
+  gtk_container_child_set (GTK_CONTAINER (overlay), button, "blur", 5.0, NULL);
 
   sw = gtk_scrolled_window_new (NULL, NULL);
   gtk_container_add (GTK_CONTAINER (overlay), sw);