diff options
author | mtklein <mtklein@chromium.org> | 2015-07-13 12:06:33 -0700 |
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committer | Commit bot <commit-bot@chromium.org> | 2015-07-13 12:06:33 -0700 |
commit | e20633ed26d211e8d2b4b407c7e968944c7e60bb (patch) | |
tree | 130677b72aa8f0cb13afc7f258e159cf69d1f9fb /gm | |
parent | cd8c499f2e5126a8b5edee09d0debd8d298210fd (diff) |
Add a GM that reproduces layout test failures with my new xfermode code.
Inspired by https://storage.googleapis.com/chromium-layout-test-archives/linux_blink_rel/69169/layout-test-results/results.html
I think the root cause is overflow.
Also, adds tests for Sk16b::operator<(). It wasn't wrong, but it was suspect
(used in all three of these xfermode implementations) and so it's best to have
tests.
BUG=skia:
Review URL: https://codereview.chromium.org/1228393006
Diffstat (limited to 'gm')
-rw-r--r-- | gm/buggy_blend_modes.cpp | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/gm/buggy_blend_modes.cpp b/gm/buggy_blend_modes.cpp new file mode 100644 index 0000000000..21a6798fe0 --- /dev/null +++ b/gm/buggy_blend_modes.cpp @@ -0,0 +1,52 @@ +/* + * Copyright 2015 Google Inc. + * + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +#include "SkCanvas.h" +#include "SkGradientShader.h" +#include "gm.h" + +// This GM reproduces what I think are overflow bugs in the CPU implementations of a +// couple xfermodes. I've marked non-obvious keys to reproducing the bug // Essential! +DEF_SIMPLE_GM(buggy_blend_modes, canvas, 800, 200) { + const auto tiling = SkShader::kClamp_TileMode; + const auto flags = SkGradientShader::kInterpolateColorsInPremul_Flag; // Essential! + + SkAutoTUnref<SkShader> cyanH, magentaV; + { + SkPoint pts[] = { {0,0}, {200, 0} }; + SkColor colors[] = { 0x00000000, 0xFF00FFFF }; + cyanH.reset( + SkGradientShader::CreateLinear(pts, colors, nullptr, 2, tiling, flags, nullptr)); + } + { + SkPoint pts[] = { {0,0}, {0, 200} }; + SkColor colors[] = { 0x00000000, 0xFFFF00FF }; + magentaV.reset( + SkGradientShader::CreateLinear(pts, colors, nullptr, 2, tiling, flags, nullptr)); + } + + SkXfermode::Mode modes[] = { + SkXfermode::kDarken_Mode, // Looks ok? + SkXfermode::kHardLight_Mode, // Definitely wrong. + SkXfermode::kLighten_Mode, // Definitely wrong. + SkXfermode::kOverlay_Mode, // Same code as kHardLight_Mode. + }; + + canvas->clear(SK_ColorWHITE); + for (auto mode : modes) { + canvas->saveLayer(nullptr, nullptr); // Essential! + SkPaint h, v; + h.setShader(cyanH); + v.setShader(magentaV); + v.setXfermodeMode(mode); + canvas->drawRect(SkRect::MakeWH(200,200), h); + canvas->drawRect(SkRect::MakeWH(200,200), v); + canvas->restore(); + + canvas->translate(200, 0); + } +} |