diff options
author | Ethan Nicholas <ethannicholas@google.com> | 2018-07-19 20:10:37 +0000 |
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committer | Skia Commit-Bot <skia-commit-bot@chromium.org> | 2018-07-19 20:10:46 +0000 |
commit | 6c48e4d11ce80fa5cfef56e13b2d5847fe94a7cc (patch) | |
tree | 57e5d832d16aa9a0447e5102fe9811e39f8403d9 /src/gpu/effects/GrDitherEffect.fp | |
parent | 736db1081b378ac8c167dfbc0322470d28c1cb3e (diff) |
Reland "Revert "added GrSkSLFP and converted DitherEffect to use it""
This reverts commit 97ae0c89025dfd791047f5701e57d58da37c125c.
Reason for revert: Breaking ANGLE.
Original change's description:
> Revert "Revert "added GrSkSLFP and converted DitherEffect to use it""
>
> This reverts commit f2030783094e502fb74221077a5ee7cb41287fe4.
>
> Bug: skia:
> Change-Id: Icaaa8b3ea652a8f126bfbcc788a360493a7ebe3e
> Reviewed-on: https://skia-review.googlesource.com/137391
> Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
> Reviewed-by: Brian Salomon <bsalomon@google.com>
TBR=bsalomon@google.com,robertphillips@google.com,ethannicholas@google.com
Change-Id: I65d6d2707fceab0a99121c528d1b848d23e34bfa
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/142588
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Diffstat (limited to 'src/gpu/effects/GrDitherEffect.fp')
-rw-r--r-- | src/gpu/effects/GrDitherEffect.fp | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/src/gpu/effects/GrDitherEffect.fp b/src/gpu/effects/GrDitherEffect.fp new file mode 100644 index 0000000000..ed6c0e6b70 --- /dev/null +++ b/src/gpu/effects/GrDitherEffect.fp @@ -0,0 +1,85 @@ +/* + * Copyright 2018 Google Inc. + * + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +// This controls the range of values added to color channels +layout(key) in int rangeType; + +@make { + static std::unique_ptr<GrFragmentProcessor> Make(GrPixelConfig dstConfig) { + int rangeType; + switch (dstConfig) { + case kGray_8_GrPixelConfig: + case kGray_8_as_Lum_GrPixelConfig: + case kGray_8_as_Red_GrPixelConfig: + case kRGBA_8888_GrPixelConfig: + case kRGB_888_GrPixelConfig: + case kBGRA_8888_GrPixelConfig: + rangeType = 0; + break; + case kRGB_565_GrPixelConfig: + rangeType = 1; + break; + case kRGBA_4444_GrPixelConfig: + rangeType = 2; + break; + case kUnknown_GrPixelConfig: + case kSRGBA_8888_GrPixelConfig: + case kSBGRA_8888_GrPixelConfig: + case kRGBA_1010102_GrPixelConfig: + case kAlpha_half_GrPixelConfig: + case kAlpha_half_as_Red_GrPixelConfig: + case kRGBA_float_GrPixelConfig: + case kRG_float_GrPixelConfig: + case kRGBA_half_GrPixelConfig: + case kAlpha_8_GrPixelConfig: + case kAlpha_8_as_Alpha_GrPixelConfig: + case kAlpha_8_as_Red_GrPixelConfig: + return nullptr; + } + return std::unique_ptr<GrFragmentProcessor>(new GrDitherEffect(rangeType)); + } +} + +void main() { + half value; + half range; + @switch (rangeType) { + case 0: + range = 1.0 / 255.0; + break; + case 1: + range = 1.0 / 63.0; + break; + default: + // Experimentally this looks better than the expected value of 1/15. + range = 1.0 / 15.0; + break; + } + @if (sk_Caps.integerSupport) { + // This ordered-dither code is lifted from the cpu backend. + uint x = uint(sk_FragCoord.x); + uint y = uint(sk_FragCoord.y); + uint m = (y & 1) << 5 | (x & 1) << 4 | + (y & 2) << 2 | (x & 2) << 1 | + (y & 4) >> 1 | (x & 4) >> 2; + value = half(m) * 1.0 / 64.0 - 63.0 / 128.0; + } else { + // Simulate the integer effect used above using step/mod. For speed, simulates a 4x4 + // dither pattern rather than an 8x8 one. + half4 modValues = mod(sk_FragCoord.xyxy, half4(2.0, 2.0, 4.0, 4.0)); + half4 stepValues = step(modValues, half4(1.0, 1.0, 2.0, 2.0)); + value = dot(stepValues, half4(8.0 / 16.0, 4.0 / 16.0, 2.0 / 16.0, 1.0 / 16.0)) - 15.0 / 32.0; + } + // For each color channel, add the random offset to the channel value and then clamp + // between 0 and alpha to keep the color premultiplied. + sk_OutColor = half4(clamp(sk_InColor.rgb + value * range, 0, sk_InColor.a), sk_InColor.a); +} + +@test(testData) { + float range = testData->fRandom->nextRangeF(0.001f, 0.05f); + return std::unique_ptr<GrFragmentProcessor>(new GrDitherEffect(range)); +} |