Stop ping ponging AA in SkGpuDevice

src/gpu/SkGpuDevice.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkGpuDevice.h"
 
 #include "GrBlurUtils.h"
@@ skipping 1014 matching lines @@
         srcRect.fRight >= width && srcRect.fBottom >= height) {
         constraint = SkCanvas::kFast_SrcRectConstraint;
     }
 
     // If the render target is not msaa and draw is antialiased, we call
     // drawRect instead of drawing on the render target directly.
     // FIXME: the tiled bitmap code path doesn't currently support
     // anti-aliased edges, we work around that for now by drawing directly
     // if the image size exceeds maximum texture size.
     int maxTextureSize = fContext->caps()->maxTextureSize();
-    bool directDraw = fRenderTarget->isUnifiedMultisampled() ||
-                      !paint.isAntiAlias() ||
-                      bitmap.width() > maxTextureSize ||
-                      bitmap.height() > maxTextureSize;
+    bool drawAA = !fRenderTarget->isUnifiedMultisampled() &&
+                  paint.isAntiAlias() &&
+                  bitmap.width() <= maxTextureSize &&
+                  bitmap.height() <= maxTextureSize;
 
-    // we check whether dst rect are pixel aligned
-    if (!directDraw) {
-        bool staysRect = draw.fMatrix->rectStaysRect();
-
-        if (staysRect) {
-            SkRect rect;
-            SkRect dstRect = SkRect::MakeXYWH(0, 0, dstSize.fWidth, dstSize.fHeight);
-            draw.fMatrix->mapRect(&rect, dstRect);
-            const SkScalar *scalars = rect.asScalars();
-            bool isDstPixelAligned = true;
-            for (int i = 0; i < 4; i++) {
-                if (!SkScalarIsInt(scalars[i])) {
-                    isDstPixelAligned = false;
-                    break;
-                }
-            }
-
-            if (isDstPixelAligned)
-                directDraw = true;
-        }
-    }
-
-    if (paint.getMaskFilter() || !directDraw) {
+    if (paint.getMaskFilter() || drawAA) {
         // Convert the bitmap to a shader so that the rect can be drawn
         // through drawRect, which supports mask filters.
         SkBitmap        tmp;    // subset of bitmap, if necessary
         const SkBitmap* bitmapPtr = &bitmap;
         SkMatrix srcRectToDstRect;
         if (srcRectPtr) {
             srcRectToDstRect.setTranslate(-srcRectPtr->fLeft, -srcRectPtr->fTop);
             srcRectToDstRect.postScale(dstSize.fWidth / srcRectPtr->width(),
                                        dstSize.fHeight / srcRectPtr->height());
             // In bleed mode we position and trim the bitmap based on the src rect which is
@@ skipping 849 matching lines @@
 #endif
 }
 
 SkImageFilter::Cache* SkGpuDevice::getImageFilterCache() {
     // We always return a transient cache, so it is freed after each
     // filter traversal.
     return SkImageFilter::Cache::Create(kDefaultImageFilterCacheSize);
 }
 
 #endif