Fix SkTileImageFilter when srcRect is a superset of bitmap bounds.

src/effects/SkTileImageFilter.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkTileImageFilter.h"
 #include "SkBitmap.h"
 #include "SkCanvas.h"
@@ skipping 36 matching lines @@
     if (!fSrcRect.width() || !fSrcRect.height() || !w || !h) {
         return false;
     }
 
     SkRect srcRect;
     ctx.ctm().mapRect(&srcRect, fSrcRect);
     SkIRect srcIRect;
     srcRect.roundOut(&srcIRect);
     srcIRect.offset(-srcOffset);
     SkBitmap subset;
-    SkIRect bounds;
-    source.getBounds(&bounds);
+    SkIRect srcBounds;
+    source.getBounds(&srcBounds);
 
-    if (!srcIRect.intersect(bounds)) {
+    if (!SkIRect::Intersects(srcIRect, srcBounds)) {
         offset->fX = offset->fY = 0;
         return true;
-    } else if (!source.extractSubset(&subset, srcIRect)) {
-        return false;
     }
+    if (srcBounds.contains(srcIRect)) {
+        if (!source.extractSubset(&subset, srcIRect)) {
+            return false;
+        }
+    } else {

[robertphillips, 2016/01/11 13:31:54]

\n somewhere ?
Maybe "static bool kWillTiledResult = true;" ?

[Stephen White, 2016/01/11 16:20:30]

Done.

+        SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(srcIRect.width(), srcIRect.height(), true));
+        if (!device) {
+            return false;
+        }
+        SkCanvas canvas(device);
+        canvas.clear(0x0);

[reed1, 2016/01/10 02:25:02]

is the clear needed? I thought our devices were already cleared (but not sure)

[Stephen White, 2016/01/11 16:20:30]

I wasn't sure either. Removed and the tests seem ok.

+        canvas.drawBitmap(src, SkIntToScalar(srcOffset.x()),
+                               SkIntToScalar(srcOffset.y()));
+        subset = device->accessBitmap(false);
+    }
+    SkASSERT(subset.width() == srcIRect.width());
+    SkASSERT(subset.height() == srcIRect.height());
 
     SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(w, h));
     if (nullptr == device.get()) {
         return false;
     }
     SkCanvas canvas(device);
     SkPaint paint;
     paint.setXfermodeMode(SkXfermode::kSrc_Mode);
 
-    SkMatrix shaderMatrix;
-    shaderMatrix.setTranslate(SkIntToScalar(srcOffset.fX),
-                              SkIntToScalar(srcOffset.fY));
     SkAutoTUnref<SkShader> shader(SkShader::CreateBitmapShader(subset,
-                                  SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode,
-                                  &shaderMatrix));
+                                  SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode));
     paint.setShader(shader);
     canvas.translate(-dstRect.fLeft, -dstRect.fTop);
     canvas.drawRect(dstRect, paint);
     *dst = device->accessBitmap(false);
     offset->fX = dstIRect.fLeft;
     offset->fY = dstIRect.fTop;
     return true;
 }
 
 void SkTileImageFilter::onFilterNodeBounds(const SkIRect& src, const SkMatrix& ctm,
@@ skipping 44 matching lines @@
     str->appendf(" dst: %.2f %.2f %.2f %.2f",
                  fDstRect.fLeft, fDstRect.fTop, fDstRect.fRight, fDstRect.fBottom);
     if (this->getInput(0)) {
         str->appendf("input: (");
         this->getInput(0)->toString(str);
         str->appendf(")");
     }
     str->append(")");
 }
 #endif