skia2/include/private/SkImageInfoPriv.h
Brian Osman 3ea317cb6f Remove checks that insist on kOpaque for some color types
For destinations, Premul vs. Unpremul is actually meaningful
for these color types - it determines whether or not we divide
through by alpha after blending. Opaqueness ought to just be
a performance hint, and only for sources.

Bug: skia:
Change-Id: I801a64316ec9c92642982cd2096f8bec9a7855f3
Reviewed-on: https://skia-review.googlesource.com/c/161423
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
2018-10-11 15:30:55 +00:00

120 lines
4.4 KiB
C

/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkImageInfoPriv_DEFINED
#define SkImageInfoPriv_DEFINED
#include "SkImageInfo.h"
enum SkColorTypeComponentFlag {
kRed_SkColorTypeComponentFlag = 0x1,
kGreen_SkColorTypeComponentFlag = 0x2,
kBlue_SkColorTypeComponentFlag = 0x4,
kAlpha_SkColorTypeComponentFlag = 0x8,
kGray_SkColorTypeComponentFlag = 0x10,
kRGB_SkColorTypeComponentFlags = kRed_SkColorTypeComponentFlag |
kGreen_SkColorTypeComponentFlag |
kBlue_SkColorTypeComponentFlag,
kRGBA_SkColorTypeComponentFlags = kRGB_SkColorTypeComponentFlags |
kAlpha_SkColorTypeComponentFlag,
};
static inline uint32_t SkColorTypeComponentFlags(SkColorType ct) {
switch (ct) {
case kUnknown_SkColorType: return 0;
case kAlpha_8_SkColorType: return kAlpha_SkColorTypeComponentFlag;
case kRGB_565_SkColorType: return kRGB_SkColorTypeComponentFlags;
case kARGB_4444_SkColorType: return kRGBA_SkColorTypeComponentFlags;
case kRGBA_8888_SkColorType: return kRGBA_SkColorTypeComponentFlags;
case kRGB_888x_SkColorType: return kRGB_SkColorTypeComponentFlags;
case kBGRA_8888_SkColorType: return kRGBA_SkColorTypeComponentFlags;
case kRGBA_1010102_SkColorType: return kRGBA_SkColorTypeComponentFlags;
case kRGB_101010x_SkColorType: return kRGB_SkColorTypeComponentFlags;
case kGray_8_SkColorType: return kGray_SkColorTypeComponentFlag;
case kRGBA_F16_SkColorType: return kRGBA_SkColorTypeComponentFlags;
case kRGBA_F32_SkColorType: return kRGBA_SkColorTypeComponentFlags;
}
return 0;
}
static inline bool SkColorTypeIsAlphaOnly(SkColorType ct) {
return kAlpha_SkColorTypeComponentFlag == SkColorTypeComponentFlags(ct);
}
static inline bool SkAlphaTypeIsValid(unsigned value) {
return value <= kLastEnum_SkAlphaType;
}
static inline bool SkColorTypeIsGray(SkColorType ct) {
auto flags = SkColorTypeComponentFlags(ct);
// Currently assuming that a color type has only gray or does not have gray.
SkASSERT(!(kGray_SkColorTypeComponentFlag & flags) || kGray_SkColorTypeComponentFlag == flags);
return kGray_SkColorTypeComponentFlag == flags;
}
static int SkColorTypeShiftPerPixel(SkColorType ct) {
switch (ct) {
case kUnknown_SkColorType: return 0;
case kAlpha_8_SkColorType: return 0;
case kRGB_565_SkColorType: return 1;
case kARGB_4444_SkColorType: return 1;
case kRGBA_8888_SkColorType: return 2;
case kRGB_888x_SkColorType: return 2;
case kBGRA_8888_SkColorType: return 2;
case kRGBA_1010102_SkColorType: return 2;
case kRGB_101010x_SkColorType: return 2;
case kGray_8_SkColorType: return 0;
case kRGBA_F16_SkColorType: return 3;
case kRGBA_F32_SkColorType: return 4;
}
return 0;
}
static inline size_t SkColorTypeMinRowBytes(SkColorType ct, int width) {
return width * SkColorTypeBytesPerPixel(ct);
}
static inline bool SkColorTypeIsValid(unsigned value) {
return value <= kLastEnum_SkColorType;
}
static inline size_t SkColorTypeComputeOffset(SkColorType ct, int x, int y, size_t rowBytes) {
if (kUnknown_SkColorType == ct) {
return 0;
}
return y * rowBytes + (x << SkColorTypeShiftPerPixel(ct));
}
/**
* Returns true if |info| contains a valid combination of width, height, colorType, and alphaType.
*/
static inline bool SkImageInfoIsValid(const SkImageInfo& info) {
if (info.width() <= 0 || info.height() <= 0) {
return false;
}
const int kMaxDimension = SK_MaxS32 >> 2;
if (info.width() > kMaxDimension || info.height() > kMaxDimension) {
return false;
}
if (kUnknown_SkColorType == info.colorType() || kUnknown_SkAlphaType == info.alphaType()) {
return false;
}
return true;
}
/**
* Returns true if Skia has defined a pixel conversion from the |src| to the |dst|.
* Returns false otherwise.
*/
static inline bool SkImageInfoValidConversion(const SkImageInfo& dst, const SkImageInfo& src) {
return SkImageInfoIsValid(dst) && SkImageInfoIsValid(src);
}
#endif // SkImageInfoPriv_DEFINED