test dont-clip-layer

gm/aaclip.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 "gm.h"
 #include "SkCanvas.h"
 #include "SkPath.h"
 
+static void do_draw(SkCanvas* canvas, const SkRect& r) {
+    SkPaint paint;
+    paint.setXfermodeMode(SkXfermode::kSrc_Mode);
+    paint.setColor(0x800000FF);
+    canvas->drawRect(r, paint);
+}
+
+DEF_SIMPLE_GM(dont_clip_to_layer, canvas, 350, 120) {

[mtklein, 2016/09/06 14:05:19]

were there going to be 2 more horizontally?

[reed1, 2016/09/06 14:36:32]

The scrolling code in android sometimes does that: it creates two layers with a
"hole" in the middle. However that was harder to diagnose than this simpler
example, which exercises all of the needed code paths (and showed the bug on GPU
before the fix).

[mtklein, 2016/09/06 14:51:21]

Sorry, was just wondering about why this was so wide.  It can probably be
120x120 right?

[reed1, 2016/09/06 15:06:29]

Ah, gotcha. Will fix.

+    SkRect r { 10, 10, 110, 110 };
+    SkRect r0 = SkRect::MakeXYWH(r.left(), r.top(), r.width(), r.height()/2);
+
+    SkCanvas::SaveLayerRec rec;
+    rec.fPaint = nullptr;
+    rec.fBounds = &r0;
+    rec.fBackdrop = nullptr;
+    rec.fSaveLayerFlags = 1 << 31;//SkCanvas::kDontClipToLayer_Legacy_SaveLayerFlag;
+    canvas->saveLayer(rec);

[mtklein, 2016/09/06 14:05:19]

Can you add a comment about the effect that we're testing here?  (I think if you
put it above the DEF_SIMPLE_GM, Joe's comments harvester will pick it up.)  I
don't understand why the two halves of the square end up with the colors they
do.

[reed1, 2016/09/06 14:36:32]

Done.

+    do_draw(canvas, r);
+    canvas->restore();
+}
+
 /** Draw a 2px border around the target, then red behind the target;
     set the clip to match the target, then draw >> the target in blue.
 */
 
 static void draw(SkCanvas* canvas, SkRect& target, int x, int y) {
     SkPaint borderPaint;
     borderPaint.setColor(SkColorSetRGB(0x0, 0xDD, 0x0));
     borderPaint.setAntiAlias(true);
     SkPaint backgroundPaint;
     backgroundPaint.setColor(SkColorSetRGB(0xDD, 0x0, 0x0));
@@ skipping 232 matching lines @@
         canvas->translate(80, 10);
         this->drawAndClip(canvas, fVPath, 200, 0);
         canvas->translate(0, 200);
         this->drawAndClip(canvas, fHPath, 200, 0);
     }
 
 private:
     typedef skiagm::GM INHERITED;
 };
 DEF_GM(return new ClipCubicGM;)