Add repro GM for GPU clipped-AA vs. non-AA drawRect discrepancy
In the clip stack we were manually rounding out non-AA clip rects but leaving the hardening of non-AA drawRects up to the GPU. In some border cases the GPU can truncate rather than round out resulting in visual discrepancies.
BUG=423834
Committed: https://skia.googlesource.com/skia/+/933a03fecb65c83f81cf65d5cf9870c69aa379ff
Review URL: https://codereview.chromium.org/839883003
diff --git a/gm/clipdrawdraw.cpp b/gm/clipdrawdraw.cpp
new file mode 100644
index 0000000..0e471dd
--- /dev/null
+++ b/gm/clipdrawdraw.cpp
@@ -0,0 +1,92 @@
+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "gm.h"
+
+namespace skiagm {
+
+// This GM exercises the use case found in crbug.com/423834.
+// The following pattern:
+// clipRect(r);
+// drawRect(r, withAA);
+// drawRect(r, noAA);
+// can leave 1 pixel wide remnants of the first rect.
+class ClipDrawDrawGM : public GM {
+public:
+ ClipDrawDrawGM() {
+ this->setBGColor(0xFFCCCCCC);
+ }
+
+protected:
+ SkString onShortName() SK_OVERRIDE {
+ return SkString("clipdrawdraw");
+ }
+
+ SkISize onISize() SK_OVERRIDE {
+ return SkISize::Make(512, 512);
+ }
+
+ // Vertical remnant
+ static void draw1(SkCanvas* canvas) {
+ SkPaint p;
+ p.setAntiAlias(true);
+
+ const SkRect rect = SkRect::MakeXYWH(8, 9, 404, 313);
+
+ canvas->save();
+
+ canvas->scale(0.5f, 0.5f);
+ canvas->translate(265, 265);
+
+ canvas->save();
+ canvas->clipRect(rect);
+ canvas->drawRect(rect, p);
+ canvas->restore();
+
+ p.setColor(SK_ColorWHITE);
+ p.setAntiAlias(false);
+ canvas->drawRect(rect, p);
+ canvas->restore();
+ }
+
+ // Horizontal remnant
+ static void draw2(SkCanvas* canvas) {
+ SkPaint p;
+ p.setAntiAlias(true);
+
+ const SkRect rect = SkRect::MakeXYWH(8, 9, 404, 313);
+
+ canvas->save();
+
+ canvas->translate(200.800003f, 172.299988f);
+ canvas->scale(0.8f, 0.8f);
+
+ canvas->save();
+ canvas->clipRect(rect);
+ canvas->drawRect(rect, p);
+ canvas->restore();
+
+ p.setColor(SK_ColorWHITE);
+ p.setAntiAlias(false);
+ canvas->drawRect(rect, p);
+ canvas->restore();
+ }
+
+ void onDraw(SkCanvas* canvas) SK_OVERRIDE {
+ draw1(canvas);
+ draw2(canvas);
+ }
+
+private:
+ typedef GM INHERITED;
+};
+
+//////////////////////////////////////////////////////////////////////////////
+
+DEF_GM(return SkNEW(ClipDrawDrawGM);)
+
+}
diff --git a/gyp/gmslides.gypi b/gyp/gmslides.gypi
index 80d7a24..6ee6bd7 100644
--- a/gyp/gmslides.gypi
+++ b/gyp/gmslides.gypi
@@ -40,6 +40,7 @@
'../gm/blurroundrect.cpp',
'../gm/circles.cpp',
'../gm/circularclips.cpp',
+ '../gm/clipdrawdraw.cpp',
'../gm/clip_strokerect.cpp',
'../gm/clippedbitmapshaders.cpp',
'../gm/cgms.cpp',
