Avoid creating trivial shadow nodes

The Vulkan renderer creates a fallback surface for each shadow
node, even if we end up not rendering anything to it. Avoiding
this is a nice optimization.

1 files changed, 27 insertions, 0 deletions

diff --git a/gtk/gtkcssshadowsvalue.c b/gtk/gtkcssshadowsvalue.c
index bd687dc156..fcb6097cea 100644
--- a/gtk/gtkcssshadowsvalue.c
+++ b/gtk/gtkcssshadowsvalue.c
@@ -24,6 +24,7 @@
 #include <math.h>
 
 #include "gtkcssshadowvalueprivate.h"
+#include "gtksnapshot.h"
 
 #include <string.h>
 
@@ -393,3 +394,29 @@ _gtk_css_shadows_value_get_extents (const GtkCssValue *shadows,
 
   *border = b;
 }
+
+gboolean
+gtk_css_shadows_value_push_snapshot (const GtkCssValue *value,
+                                     GtkSnapshot       *snapshot)
+{
+  gboolean need_shadow = FALSE;
+  int i;
+
+  for (i = 0; i < value->len; i++)
+    {
+      if (!gtk_css_shadow_value_is_clear (value->values[i]))
+        {
+          need_shadow = TRUE;
+          break;
+        }
+    }
+
+  if (need_shadow)
+    {
+      GskShadow *shadows = g_newa (GskShadow, value->len);
+      gtk_css_shadows_value_get_shadows (value, shadows);
+      gtk_snapshot_push_shadow (snapshot, shadows, value->len, "Shadow<%u>", value->len);
+    }
+
+  return need_shadow;
+}