| /* |
| * Copyright 2017 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| /** |
| * Returns true if |info| contains a valid combination of width, height, colorType, alphaType, |
| * colorSpace. Returns false otherwise. |
| */ |
| static inline bool SkImageInfoIsValid(const SkImageInfo& info) { |
| if (info.width() <= 0 || info.height() <= 0) { |
| return false; |
| } |
| |
| if (kUnknown_SkColorType == info.colorType() || kUnknown_SkAlphaType == info.alphaType()) { |
| return false; |
| } |
| |
| if (kOpaque_SkAlphaType != info.alphaType() && |
| (kRGB_565_SkColorType == info.colorType() || kGray_8_SkColorType == info.colorType())) { |
| return false; |
| } |
| |
| if (kRGBA_F16_SkColorType == info.colorType() && |
| (!info.colorSpace() || !info.colorSpace()->gammaIsLinear())) { |
| return false; |
| } |
| |
| if (info.colorSpace() && |
| (!info.colorSpace()->gammaCloseToSRGB() && !info.colorSpace()->gammaIsLinear())) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| /** |
| * Returns true if Skia has defined a pixel conversion from the |src| to the |dst|. |
| * Returns false otherwise. Some discussion of false cases: |
| * We will not convert to kIndex8 unless |src| is kIndex8. This is possible only |
| * in some cases and likley inefficient. |
| * We do not convert to kGray8 when the |src| is not kGray8. We may add this |
| * feature - it just requires some work to convert to luminance while handling color |
| * spaces correctly. Currently no one is asking for this. |
| * We will not convert from kAlpha8 when the |dst| is not kAlpha8. This would require |
| * inventing color information. |
| * We will not convert to kOpaque when the |src| is not kOpaque. This could be |
| * implemented to set all the alpha values to 1, but there is still some ambiguity - |
| * should we use kPremul or kUnpremul color values with the opaque alphas? Or should |
| * we just use whatever the |src| alpha is? In the future, we could choose to clearly |
| * define this, but currently no one is asking for this feature. |
| */ |
| static inline bool SkImageInfoValidConversion(const SkImageInfo& dst, const SkImageInfo& src) { |
| if (!SkImageInfoIsValid(dst) || !SkImageInfoIsValid(src)) { |
| return false; |
| } |
| |
| if (kIndex_8_SkColorType == dst.colorType() && kIndex_8_SkColorType != src.colorType()) { |
| return false; |
| } |
| |
| if (kGray_8_SkColorType == dst.colorType() && kGray_8_SkColorType != src.colorType()) { |
| return false; |
| } |
| |
| if (kAlpha_8_SkColorType != dst.colorType() && kAlpha_8_SkColorType == src.colorType()) { |
| return false; |
| } |
| |
| if (kOpaque_SkAlphaType == dst.alphaType() && kOpaque_SkAlphaType != src.alphaType()) { |
| return false; |
| } |
| |
| return true; |
| } |