Fix DDL blur image filter

This fixes on of the DDL render problems in the imageblurclampmode GM.

Bug: skia:7765
Change-Id: I2d6779183cd47b63b47f9f071c2266643d222feb
Reviewed-on: https://skia-review.googlesource.com/125000
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

1 files changed, 14 insertions, 7 deletions

diff --git a/src/gpu/effects/GrGaussianConvolutionFragmentProcessor.cpp b/src/gpu/effects/GrGaussianConvolutionFragmentProcessor.cpp
index fdd4990328..c546f8c9c8 100644
--- a/src/gpu/effects/GrGaussianConvolutionFragmentProcessor.cpp
+++ b/src/gpu/effects/GrGaussianConvolutionFragmentProcessor.cpp
@@ -147,15 +147,22 @@ void GrGLConvolutionEffect::onSetData(const GrGLSLProgramDataManager& pdman,
         }
         if (Direction::kX == conv.direction()) {
             SkScalar inv = SkScalarInvert(SkIntToScalar(texture.width()));
-            pdman.set2f(fBoundsUni, inv * bounds[0], inv * bounds[1]);
+            bounds[0] *= inv;
+            bounds[1] *= inv;
         } else {
             SkScalar inv = SkScalarInvert(SkIntToScalar(texture.height()));
             if (proxy->origin() != kTopLeft_GrSurfaceOrigin) {
-                pdman.set2f(fBoundsUni, 1.0f - (inv * bounds[1]), 1.0f - (inv * bounds[0]));
+                float tmp = bounds[0];
+                bounds[0] = 1.0f - (inv * bounds[1]);
+                bounds[1] = 1.0f - (inv * tmp);
             } else {
-                pdman.set2f(fBoundsUni, inv * bounds[1], inv * bounds[0]);
+                bounds[0] *= inv;
+                bounds[1] *= inv;
             }
         }
+
+        SkASSERT(bounds[0] <= bounds[1]);
+        pdman.set2f(fBoundsUni, bounds[0], bounds[1]);
     }
     int width = conv.width();
 
@@ -274,12 +281,12 @@ std::unique_ptr<GrFragmentProcessor> GrGaussianConvolutionFragmentProcessor::Tes
     Direction dir;
     if (d->fRandom->nextBool()) {
         dir = Direction::kX;
-        bounds[0] = d->fRandom->nextRangeU(0, proxy->width()-1);
-        bounds[1] = d->fRandom->nextRangeU(bounds[0], proxy->width()-1);
+        bounds[0] = d->fRandom->nextRangeU(0, proxy->width()-2);
+        bounds[1] = d->fRandom->nextRangeU(bounds[0]+1, proxy->width()-1);
     } else {
         dir = Direction::kY;
-        bounds[0] = d->fRandom->nextRangeU(0, proxy->height()-1);
-        bounds[1] = d->fRandom->nextRangeU(bounds[0], proxy->height()-1);
+        bounds[0] = d->fRandom->nextRangeU(0, proxy->height()-2);
+        bounds[1] = d->fRandom->nextRangeU(bounds[0]+1, proxy->height()-1);
     }
 
     int radius = d->fRandom->nextRangeU(1, kMaxKernelRadius);