/* * Copyright 2016 Google Inc. * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ #include "Test.h" #if SK_SUPPORT_GPU #include "GrCaps.h" #include "GrClip.h" #include "GrContext.h" #include "GrRenderTargetContext.h" #include "GrResourceProvider.h" #include "SkCanvas.h" #include "SkSurface.h" #include "gl/GrGLGpu.h" // using anonymous namespace because these functions are used as template params. namespace { /** convert 0..1 srgb value to 0..1 linear */ float srgb_to_linear(float srgb) { if (srgb <= 0.04045f) { return srgb / 12.92f; } else { return powf((srgb + 0.055f) / 1.055f, 2.4f); } } /** convert 0..1 linear value to 0..1 srgb */ float linear_to_srgb(float linear) { if (linear <= 0.0031308) { return linear * 12.92f; } else { return 1.055f * powf(linear, 1.f / 2.4f) - 0.055f; } } } static bool check_value(U8CPU value, U8CPU expected, U8CPU error) { if (value >= expected) { return (value - expected) <= error; } else { return (expected - value) <= error; } } void read_and_check_pixels(skiatest::Reporter* reporter, GrTexture* texture, U8CPU expected, U8CPU error, const char* subtestName) { int w = texture->width(); int h = texture->height(); SkAutoTMalloc readData(w * h); memset(readData.get(), 0, sizeof(uint32_t) * w * h); if (!texture->readPixels(0, 0, w, h, texture->config(), readData.get())) { ERRORF(reporter, "Could not read pixels for %s.", subtestName); return; } for (int j = 0; j < h; ++j) { for (int i = 0; i < w; ++i) { uint32_t read = readData[j * w + i]; bool success = check_value(read & 0xff, expected, error) && check_value((read >> 8) & 0xff, expected, error) && check_value((read >> 16) & 0xff, expected, error); if (!success) { ERRORF(reporter, "Expected 0xff%02x%02x%02x, read back as 0x%08x in %s at %d, %d.", expected, expected, expected, read, subtestName, i, j); return; } } } } DEF_GPUTEST_FOR_GL_RENDERING_CONTEXTS(SRGBMipMaps, reporter, ctxInfo) { GrContext* context = ctxInfo.grContext(); if (!context->caps()->srgbSupport()) { return; } const int rtS = 16; const int texS = rtS * 2; // Fill texture with a dither of black and 60% sRGB (~ 32.5% linear) gray. Although there is // only one likely failure mode (doing a direct downsample of the sRGB values), this pattern // maximizes the minimum error across all three conceivable failure modes: // 1) Likely incorrect: // (A + B) / 2 // 2) No input decode, decode output: // linear_to_srgb((A + B) / 2) // 3) Decode input, no output encode: // (srgb_to_linear(A) + srgb_to_linear(B)) / 2 const U8CPU srgb60 = sk_float_round2int(0.6f * 255.0f); static const SkPMColor colors[2] = { SkPackARGB32(0xFF, srgb60, srgb60, srgb60), SkPackARGB32(0xFF, 0x00, 0x00, 0x00) }; uint32_t texData[texS * texS]; for (int y = 0; y < texS; ++y) { for (int x = 0; x < texS; ++x) { texData[y * texS + x] = colors[(x + y) % 2]; } } // We can be pretty generous with the error detection, thanks to the choice of input. // The closest likely failure mode is off by > 0.1, so anything that encodes within // 10/255 of optimal is more than good enough for this test. const U8CPU expectedSRGB = sk_float_round2int( linear_to_srgb(srgb_to_linear(srgb60 / 255.0f) / 2.0f) * 255.0f); const U8CPU expectedLinear = srgb60 / 2; const U8CPU error = 10; // Create our test texture GrSurfaceDesc desc; desc.fFlags = kNone_GrSurfaceFlags; desc.fConfig = kSRGBA_8888_GrPixelConfig; desc.fWidth = texS; desc.fHeight = texS; GrResourceProvider* resourceProvider = context->resourceProvider(); sk_sp proxy = GrSurfaceProxy::MakeDeferred(*context->caps(), resourceProvider, desc, SkBudgeted::kNo, texData, 0); // Create two render target contexts (L32 and S32) sk_sp srgbColorSpace = SkColorSpace::MakeSRGB(); sk_sp l32RenderTargetContext = context->makeRenderTargetContext( SkBackingFit::kExact, rtS, rtS, kRGBA_8888_GrPixelConfig, nullptr); sk_sp s32RenderTargetContext = context->makeRenderTargetContext( SkBackingFit::kExact, rtS, rtS, kSRGBA_8888_GrPixelConfig, std::move(srgbColorSpace)); SkRect rect = SkRect::MakeWH(SkIntToScalar(rtS), SkIntToScalar(rtS)); GrNoClip noClip; GrPaint paint; paint.setPorterDuffXPFactory(SkBlendMode::kSrc); GrSamplerParams mipMapParams(SkShader::kRepeat_TileMode, GrSamplerParams::kMipMap_FilterMode); paint.addColorTextureProcessor(context, std::move(proxy), nullptr, SkMatrix::MakeScale(rtS), mipMapParams); // 1) Draw texture to S32 surface (should generate/use sRGB mips) paint.setGammaCorrect(true); s32RenderTargetContext->drawRect(noClip, GrPaint(paint), GrAA::kNo, SkMatrix::I(), rect); read_and_check_pixels(reporter, s32RenderTargetContext->asTexture().get(), expectedSRGB, error, "first render of sRGB"); // 2) Draw texture to L32 surface (should generate/use linear mips) paint.setGammaCorrect(false); l32RenderTargetContext->drawRect(noClip, GrPaint(paint), GrAA::kNo, SkMatrix::I(), rect); // Right now, this test only runs on GL (because Vulkan doesn't support legacy mip-mapping // skbug.com/5048). On GL, we may not have sRGB decode support. In that case, rendering sRGB // textures to a legacy surface produces nonsense, so this part of the test is meaningless. // // We also skip this part of the test on command buffer (via srgbDecodeDisableAffectsMipmaps), // because that implementation of the extension doesn't ensure that mips respect the setting. // // TODO: Once Vulkan supports legacy mip-mapping, we can promote this to GrCaps. Right now, // Vulkan has most of the functionality, but not the mip-mapping part that's being tested here. GrGLGpu* glGpu = static_cast(context->getGpu()); if (glGpu->glCaps().srgbDecodeDisableSupport() && glGpu->glCaps().srgbDecodeDisableAffectsMipmaps()) { read_and_check_pixels(reporter, l32RenderTargetContext->asTexture().get(), expectedLinear, error, "re-render as linear"); } // 3) Go back to sRGB paint.setGammaCorrect(true); s32RenderTargetContext->drawRect(noClip, std::move(paint), GrAA::kNo, SkMatrix::I(), rect); read_and_check_pixels(reporter, s32RenderTargetContext->asTexture().get(), expectedSRGB, error, "re-render as sRGB"); } #endif