tunnel down texture-size-constraint to imagefilters

src/effects/SkMorphologyImageFilter.cpp

Index: src/effects/SkMorphologyImageFilter.cpp
diff --git a/src/effects/SkMorphologyImageFilter.cpp b/src/effects/SkMorphologyImageFilter.cpp
index 4e08d9dd733148b369105604461332dd09ce534e..546e6f5d93141cecf220cdd7748a78a685a8e8f2 100644
--- a/src/effects/SkMorphologyImageFilter.cpp
+++ b/src/effects/SkMorphologyImageFilter.cpp
@@ -547,7 +547,8 @@ bool apply_morphology(const SkBitmap& input,
                       const SkIRect& rect,
                       GrMorphologyEffect::MorphologyType morphType,
                       SkISize radius,
-                      SkBitmap* dst) {
+                      SkBitmap* dst,
+                      GrTextureProvider::SizeConstraint constraint) {
     SkAutoTUnref<GrTexture> srcTexture(SkRef(input.getTexture()));
     SkASSERT(srcTexture);
     GrContext* context = srcTexture->getContext();
@@ -565,7 +566,14 @@ bool apply_morphology(const SkBitmap& input,
     SkIRect srcRect = rect;
 
     if (radius.fWidth > 0) {
-        GrTexture* scratch = context->textureProvider()->createApproxTexture(desc);
+        GrTextureProvider::SizeConstraint horiConstraint = constraint;
+        if (radius.fHeight > 0) {
+            // Optimization: we will fall through and allocate the "real" texture after this one

[Stephen White, 2015/10/22 19:53:14]

For bonus points in a followup patch, do a similar optimization in the blur
image filter (for the easy and fairly common case where we have to do a bilinear
upres after blurring: scaleFactorX > 1 || scaleFactorY > 1).

[reed1, 2015/10/22 20:08:25]

Indeed. I looked at the blur code, but couldn't see a clear (finite) way to
preflight the predicate to know when which would be scratch. I agree that should
be done.

+            // so ours can be approximate (likely faster to allocate)
+            horiConstraint = GrTextureProvider::kApprox_SizeConstraint;
+        }
+
+        GrTexture* scratch = context->textureProvider()->createTexture(desc, horiConstraint);
         if (nullptr == scratch) {
             return false;
         }
@@ -589,7 +597,7 @@ bool apply_morphology(const SkBitmap& input,
         srcRect = dstRect;
     }
     if (radius.fHeight > 0) {
-        GrTexture* scratch = context->textureProvider()->createApproxTexture(desc);
+        GrTexture* scratch = context->textureProvider()->createTexture(desc, constraint);
         if (nullptr == scratch) {
             return false;
         }
@@ -647,7 +655,8 @@ bool SkMorphologyImageFilter::filterImageGPUGeneric(bool dilate,
 
     GrMorphologyEffect::MorphologyType type = dilate ? GrMorphologyEffect::kDilate_MorphologyType
                                                      : GrMorphologyEffect::kErode_MorphologyType;
-    if (!apply_morphology(input, srcBounds, type, SkISize::Make(width, height), result)) {
+    if (!apply_morphology(input, srcBounds, type, SkISize::Make(width, height), result,
+                          GrTextureProvider::FromImageFilter(ctx.sizeConstraint()))) {
         return false;
     }
     offset->fX = bounds.left();