| /* |
| * 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 "include/core/SkCanvas.h" |
| #include "include/core/SkSurface.h" |
| #include "include/gpu/GrContext.h" |
| #include "src/gpu/GrCaps.h" |
| #include "src/gpu/GrContextPriv.h" |
| #include "src/gpu/GrImageInfo.h" |
| #include "src/gpu/GrRenderTargetContext.h" |
| #include "src/gpu/GrSurfaceContext.h" |
| #include "src/gpu/SkGr.h" |
| #include "tests/Test.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; |
| } |
| } |
| } |
| |
| /** tests a conversion with an error tolerance */ |
| template <float (*CONVERT)(float)> static bool check_conversion(uint32_t input, uint32_t output, |
| float error) { |
| // alpha should always be exactly preserved. |
| if ((input & 0xff000000) != (output & 0xff000000)) { |
| return false; |
| } |
| |
| for (int c = 0; c < 3; ++c) { |
| uint8_t inputComponent = (uint8_t) ((input & (0xff << (c*8))) >> (c*8)); |
| float lower = SkTMax(0.f, (float) inputComponent - error); |
| float upper = SkTMin(255.f, (float) inputComponent + error); |
| lower = CONVERT(lower / 255.f); |
| upper = CONVERT(upper / 255.f); |
| SkASSERT(lower >= 0.f && lower <= 255.f); |
| SkASSERT(upper >= 0.f && upper <= 255.f); |
| uint8_t outputComponent = (output & (0xff << (c*8))) >> (c*8); |
| if (outputComponent < SkScalarFloorToInt(lower * 255.f) || |
| outputComponent > SkScalarCeilToInt(upper * 255.f)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** tests a forward and backward conversion with an error tolerance */ |
| template <float (*FORWARD)(float), float (*BACKWARD)(float)> |
| static bool check_double_conversion(uint32_t input, uint32_t output, float error) { |
| // alpha should always be exactly preserved. |
| if ((input & 0xff000000) != (output & 0xff000000)) { |
| return false; |
| } |
| |
| for (int c = 0; c < 3; ++c) { |
| uint8_t inputComponent = (uint8_t) ((input & (0xff << (c*8))) >> (c*8)); |
| float lower = SkTMax(0.f, (float) inputComponent - error); |
| float upper = SkTMin(255.f, (float) inputComponent + error); |
| lower = FORWARD(lower / 255.f); |
| upper = FORWARD(upper / 255.f); |
| SkASSERT(lower >= 0.f && lower <= 255.f); |
| SkASSERT(upper >= 0.f && upper <= 255.f); |
| uint8_t upperComponent = SkScalarCeilToInt(upper * 255.f); |
| uint8_t lowerComponent = SkScalarFloorToInt(lower * 255.f); |
| lower = SkTMax(0.f, (float) lowerComponent - error); |
| upper = SkTMin(255.f, (float) upperComponent + error); |
| lower = BACKWARD(lowerComponent / 255.f); |
| upper = BACKWARD(upperComponent / 255.f); |
| SkASSERT(lower >= 0.f && lower <= 255.f); |
| SkASSERT(upper >= 0.f && upper <= 255.f); |
| upperComponent = SkScalarCeilToInt(upper * 255.f); |
| lowerComponent = SkScalarFloorToInt(lower * 255.f); |
| |
| uint8_t outputComponent = (output & (0xff << (c*8))) >> (c*8); |
| if (outputComponent < lowerComponent || outputComponent > upperComponent) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| static bool check_srgb_to_linear_conversion(uint32_t srgb, uint32_t linear, float error) { |
| return check_conversion<srgb_to_linear>(srgb, linear, error); |
| } |
| |
| static bool check_linear_to_srgb_conversion(uint32_t linear, uint32_t srgb, float error) { |
| return check_conversion<linear_to_srgb>(linear, srgb, error); |
| } |
| |
| static bool check_linear_to_srgb_to_linear_conversion(uint32_t input, uint32_t output, float error) { |
| return check_double_conversion<linear_to_srgb, srgb_to_linear>(input, output, error); |
| } |
| |
| static bool check_srgb_to_linear_to_srgb_conversion(uint32_t input, uint32_t output, float error) { |
| return check_double_conversion<srgb_to_linear, linear_to_srgb>(input, output, error); |
| } |
| |
| static bool check_no_conversion(uint32_t input, uint32_t output, float error) { |
| // This is a bit of a hack to check identity transformations that may lose precision. |
| return check_srgb_to_linear_to_srgb_conversion(input, output, error); |
| } |
| |
| typedef bool (*CheckFn) (uint32_t orig, uint32_t actual, float error); |
| |
| void read_and_check_pixels(skiatest::Reporter* reporter, GrSurfaceContext* context, |
| uint32_t* origData, |
| const SkImageInfo& dstInfo, CheckFn checker, float error, |
| const char* subtestName) { |
| int w = dstInfo.width(); |
| int h = dstInfo.height(); |
| SkAutoTMalloc<uint32_t> readData(w * h); |
| memset(readData.get(), 0, sizeof(uint32_t) * w * h); |
| |
| if (!context->readPixels(dstInfo, readData.get(), 0, {0, 0})) { |
| 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 orig = origData[j * w + i]; |
| uint32_t read = readData[j * w + i]; |
| |
| if (!checker(orig, read, error)) { |
| ERRORF(reporter, "Original 0x%08x, read back as 0x%08x in %s at %d, %d).", orig, |
| read, subtestName, i, j); |
| return; |
| } |
| } |
| } |
| } |
| |
| namespace { |
| enum class Encoding { |
| kUntagged, |
| kLinear, |
| kSRGB, |
| }; |
| } |
| |
| static sk_sp<SkColorSpace> encoding_as_color_space(Encoding encoding) { |
| switch (encoding) { |
| case Encoding::kUntagged: return nullptr; |
| case Encoding::kLinear: return SkColorSpace::MakeSRGBLinear(); |
| case Encoding::kSRGB: return SkColorSpace::MakeSRGB(); |
| } |
| return nullptr; |
| } |
| |
| static const char* encoding_as_str(Encoding encoding) { |
| switch (encoding) { |
| case Encoding::kUntagged: return "untagged"; |
| case Encoding::kLinear: return "linear"; |
| case Encoding::kSRGB: return "sRGB"; |
| } |
| return nullptr; |
| } |
| |
| static constexpr int kW = 255; |
| static constexpr int kH = 255; |
| |
| static std::unique_ptr<uint32_t[]> make_data() { |
| std::unique_ptr<uint32_t[]> data(new uint32_t[kW * kH]); |
| for (int j = 0; j < kH; ++j) { |
| for (int i = 0; i < kW; ++i) { |
| data[j * kW + i] = (0xFF << 24) | (i << 16) | (i << 8) | i; |
| } |
| } |
| return data; |
| } |
| |
| static std::unique_ptr<GrSurfaceContext> make_surface_context(Encoding contextEncoding, |
| GrContext* context, |
| skiatest::Reporter* reporter) { |
| auto surfaceContext = GrRenderTargetContext::Make( |
| context, GrColorType::kRGBA_8888, encoding_as_color_space(contextEncoding), |
| SkBackingFit::kExact, {kW, kH}, 1, GrMipMapped::kNo, GrProtected::kNo, |
| kBottomLeft_GrSurfaceOrigin, SkBudgeted::kNo); |
| if (!surfaceContext) { |
| ERRORF(reporter, "Could not create %s surface context.", encoding_as_str(contextEncoding)); |
| } |
| return surfaceContext; |
| } |
| |
| static void test_write_read(Encoding contextEncoding, Encoding writeEncoding, Encoding readEncoding, |
| float error, CheckFn check, GrContext* context, |
| skiatest::Reporter* reporter) { |
| auto surfaceContext = make_surface_context(contextEncoding, context, reporter); |
| if (!surfaceContext) { |
| return; |
| } |
| auto writeII = SkImageInfo::Make(kW, kH, kRGBA_8888_SkColorType, kPremul_SkAlphaType, |
| encoding_as_color_space(writeEncoding)); |
| auto data = make_data(); |
| if (!surfaceContext->writePixels(writeII, data.get(), 0, {0, 0})) { |
| ERRORF(reporter, "Could not write %s to %s surface context.", |
| encoding_as_str(writeEncoding), encoding_as_str(contextEncoding)); |
| return; |
| } |
| |
| auto readII = SkImageInfo::Make(kW, kH, kRGBA_8888_SkColorType, kPremul_SkAlphaType, |
| encoding_as_color_space(readEncoding)); |
| SkString testName; |
| testName.printf("write %s data to a %s context and read as %s.", encoding_as_str(writeEncoding), |
| encoding_as_str(contextEncoding), encoding_as_str(readEncoding)); |
| read_and_check_pixels(reporter, surfaceContext.get(), data.get(), readII, check, error, |
| testName.c_str()); |
| } |
| |
| // Test all combinations of writePixels/readPixels where the surface context/write source/read dst |
| // are sRGB, linear, or untagged RGBA_8888. |
| DEF_GPUTEST_FOR_RENDERING_CONTEXTS(SRGBReadWritePixels, reporter, ctxInfo) { |
| GrContext* context = ctxInfo.grContext(); |
| if (!context->priv().caps()->getDefaultBackendFormat(GrColorType::kRGBA_8888_SRGB, |
| GrRenderable::kNo).isValid()) { |
| return; |
| } |
| // We allow more error on GPUs with lower precision shader variables. |
| float error = context->priv().caps()->shaderCaps()->halfIs32Bits() ? 0.5f : 1.2f; |
| // For the all-sRGB case, we allow a small error only for devices that have |
| // precision variation because the sRGB data gets converted to linear and back in |
| // the shader. |
| float smallError = context->priv().caps()->shaderCaps()->halfIs32Bits() ? 0.0f : 1.f; |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////// |
| // Write sRGB data to a sRGB context - no conversion on the write. |
| |
| // back to sRGB - no conversion. |
| test_write_read(Encoding::kSRGB, Encoding::kSRGB, Encoding::kSRGB, smallError, |
| check_no_conversion, context, reporter); |
| // Reading back to untagged should be a pass through with no conversion. |
| test_write_read(Encoding::kSRGB, Encoding::kSRGB, Encoding::kUntagged, error, |
| check_no_conversion, context, reporter); |
| |
| // Converts back to linear |
| test_write_read(Encoding::kSRGB, Encoding::kSRGB, Encoding::kLinear, error, |
| check_srgb_to_linear_conversion, context, reporter); |
| |
| // Untagged source data should be interpreted as sRGB. |
| test_write_read(Encoding::kSRGB, Encoding::kUntagged, Encoding::kSRGB, smallError, |
| check_no_conversion, context, reporter); |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////// |
| // Write linear data to a sRGB context. It gets converted to sRGB on write. The reads |
| // are all the same as the above cases where the original data was untagged. |
| test_write_read(Encoding::kSRGB, Encoding::kLinear, Encoding::kSRGB, error, |
| check_linear_to_srgb_conversion, context, reporter); |
| // When the dst buffer is untagged there should be no conversion on the read. |
| test_write_read(Encoding::kSRGB, Encoding::kLinear, Encoding::kUntagged, error, |
| check_linear_to_srgb_conversion, context, reporter); |
| test_write_read(Encoding::kSRGB, Encoding::kLinear, Encoding::kLinear, error, |
| check_linear_to_srgb_to_linear_conversion, context, reporter); |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////// |
| // Write data to an untagged context. The write does no conversion no matter what encoding the |
| // src data has. |
| for (auto writeEncoding : {Encoding::kSRGB, Encoding::kUntagged, Encoding::kLinear}) { |
| // The read from untagged to sRGB also does no conversion. |
| test_write_read(Encoding::kUntagged, writeEncoding, Encoding::kSRGB, error, |
| check_no_conversion, context, reporter); |
| // Reading untagged back as untagged should do no conversion. |
| test_write_read(Encoding::kUntagged, writeEncoding, Encoding::kUntagged, error, |
| check_no_conversion, context, reporter); |
| // Reading untagged back as linear does convert (context is source, so treated as sRGB), |
| // dst is tagged. |
| test_write_read(Encoding::kUntagged, writeEncoding, Encoding::kLinear, error, |
| check_srgb_to_linear_conversion, context, reporter); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////// |
| // Write sRGB data to a linear context - converts to sRGB on the write. |
| |
| // converts back to sRGB on read. |
| test_write_read(Encoding::kLinear, Encoding::kSRGB, Encoding::kSRGB, error, |
| check_srgb_to_linear_to_srgb_conversion, context, reporter); |
| // Reading untagged data from linear currently does no conversion. |
| test_write_read(Encoding::kLinear, Encoding::kSRGB, Encoding::kUntagged, error, |
| check_srgb_to_linear_conversion, context, reporter); |
| // Stays linear when read. |
| test_write_read(Encoding::kLinear, Encoding::kSRGB, Encoding::kLinear, error, |
| check_srgb_to_linear_conversion, context, reporter); |
| |
| // Untagged source data should be interpreted as sRGB. |
| test_write_read(Encoding::kLinear, Encoding::kUntagged, Encoding::kSRGB, error, |
| check_srgb_to_linear_to_srgb_conversion, context, reporter); |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////// |
| // Write linear data to a linear context. Does no conversion. |
| |
| // Reading to sRGB does a conversion. |
| test_write_read(Encoding::kLinear, Encoding::kLinear, Encoding::kSRGB, error, |
| check_linear_to_srgb_conversion, context, reporter); |
| // Reading to untagged does no conversion. |
| test_write_read(Encoding::kLinear, Encoding::kLinear, Encoding::kUntagged, error, |
| check_no_conversion, context, reporter); |
| // Stays linear when read. |
| test_write_read(Encoding::kLinear, Encoding::kLinear, Encoding::kLinear, error, |
| check_no_conversion, context, reporter); |
| } |