skia2/gm/crbug_892988.cpp
Brian Salomon 09181ef042 Fix dst copy bounds for aa draw contained within clip.
Bug: chromium:892988

Change-Id: I615b60facec5724fb3a7c22a2eb59f72790156a3
Reviewed-on: https://skia-review.googlesource.com/c/171001
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
2018-11-16 19:24:04 +00:00

32 lines
1.2 KiB
C++

/*
* Copyright 2018 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 "SkPaint.h"
// The root cause of this bug was that when dual source blending was not supported and we made a
// copy of the destination to perform blending we would clip the copy bounds to the current clip.
// However, it is possible for anti-aliased that are fully contained by the clip in a geometric
// sense to actually draw outside the clip in pixel space because we don't consider aa bloat when
// determining if the draw is contained by the clip.
DEF_SIMPLE_GM(crbug_892988, canvas, 256, 256) {
SkPaint paint1;
paint1.setStyle(SkPaint::kStroke_Style);
paint1.setStrokeWidth(1.f);
paint1.setAntiAlias(true);
canvas->drawRect(SkRect::MakeLTRB(11.5, 0.5, 245.5, 245.5), paint1);
canvas->clipRect(SkRect::MakeLTRB(12, 1, 244, 244), true);
SkPaint paint2;
// Use src mode with a non-opaque color to produce a blend that can't be handled with
// simple blend coefficients.
paint2.setColor(0xF0FFFFFF);
paint2.setBlendMode(SkBlendMode::kSrc);
paint2.setAntiAlias(true);
canvas->drawRect(SkRect::MakeLTRB(12, 1, 244, 244), paint2);
}