[clutter/wip/pango-share-atlas: 12/13] cogl_pipeline_equal: Handle COGL_WRAP_MODE_AUTOMATIC better

[Neil Roberts <nroberts src gnome org>]

commit bdf76567b4ee91725f44f67eda5afeeb5fa68550
Author: Neil Roberts <neil linux intel com>
Date:   Wed Mar 30 16:33:04 2011 +0100

    cogl_pipeline_equal: Handle COGL_WRAP_MODE_AUTOMATIC better
    
    When comparing the wrap modes of two pipeline layers it now considers
    COGL_WRAP_MODE_AUTOMATIC to be equivalent to CLAMP_TO_EDGE. By the
    time the pipeline is in the journal, the upper primitive code is
    expected to have overridden this wrap mode with something else if it
    wants any other behaviour. This is important for getting text to batch
    together with textures because the text explicitly sets the wrap mode
    to CLAMP_TO_EDGE on its pipeline.

 clutter/cogl/cogl/cogl-pipeline.c |   29 ++++++++++++++++++++++++++---
 1 files changed, 26 insertions(+), 3 deletions(-)
---
diff --git a/clutter/cogl/cogl/cogl-pipeline.c b/clutter/cogl/cogl/cogl-pipeline.c
index 93c5234..56e9821 100644
--- a/clutter/cogl/cogl/cogl-pipeline.c
+++ b/clutter/cogl/cogl/cogl-pipeline.c
@@ -3193,12 +3193,30 @@ _cogl_pipeline_layer_filters_equal (CoglPipelineLayer *authority0,
 }
 
 static gboolean
+compare_wrap_mode_equal (CoglPipelineWrapMode wrap_mode0,
+                         CoglPipelineWrapMode wrap_mode1)
+{
+  /* We consider AUTOMATIC to be equivalent to CLAMP_TO_EDGE because
+     the primitives code is expected to override this to something
+     else if it wants it to be behave any other way */
+  if (wrap_mode0 == COGL_PIPELINE_WRAP_MODE_AUTOMATIC)
+    wrap_mode0 = COGL_PIPELINE_WRAP_MODE_CLAMP_TO_EDGE;
+  if (wrap_mode1 == COGL_PIPELINE_WRAP_MODE_AUTOMATIC)
+    wrap_mode1 = COGL_PIPELINE_WRAP_MODE_CLAMP_TO_EDGE;
+
+  return wrap_mode0 == wrap_mode1;
+}
+
+static gboolean
 _cogl_pipeline_layer_wrap_modes_equal (CoglPipelineLayer *authority0,
                                        CoglPipelineLayer *authority1)
 {
-  if (authority0->wrap_mode_s != authority1->wrap_mode_s ||
-      authority0->wrap_mode_t != authority1->wrap_mode_t ||
-      authority0->wrap_mode_p != authority1->wrap_mode_p)
+  if (!compare_wrap_mode_equal (authority0->wrap_mode_s,
+                                authority1->wrap_mode_s) ||
+      !compare_wrap_mode_equal (authority0->wrap_mode_t,
+                                authority1->wrap_mode_t) ||
+      !compare_wrap_mode_equal (authority0->wrap_mode_p,
+                                authority1->wrap_mode_p))
     return FALSE;
 
   return TRUE;
@@ -3681,6 +3699,11 @@ _cogl_pipeline_resolve_authorities (CoglPipeline *pipeline,
  * it means that _cogl_pipeline_equal doesn't strictly compare whether the
  * pipelines are the same. If we needed those semantics we could perhaps add
  * another function or some flags to control the behaviour.
+ *
+ * XXX: Similarly when comparing the wrap modes,
+ * COGL_PIPELINE_WRAP_MODE_AUTOMATIC is considered to be the same as
+ * COGL_PIPELINE_WRAP_MODE_CLAMP_TO_EDGE because once they get to the
+ * journal stage they act exactly the same.
  */
 gboolean
 _cogl_pipeline_equal (CoglPipeline *pipeline0,