1 /* 2 * Copyright 2010 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #include "SkImageInfo.h" 9 #include "SkReadBuffer.h" 10 #include "SkWriteBuffer.h" 11 12 static bool alpha_type_is_valid(SkAlphaType alphaType) { 13 return (alphaType >= 0) && (alphaType <= kLastEnum_SkAlphaType); 14 } 15 16 static bool color_type_is_valid(SkColorType colorType) { 17 return (colorType >= 0) && (colorType <= kLastEnum_SkColorType); 18 } 19 20 void SkImageInfo::unflatten(SkReadBuffer& buffer) { 21 fWidth = buffer.read32(); 22 fHeight = buffer.read32(); 23 24 uint32_t packed = buffer.read32(); 25 SkASSERT(0 == (packed >> 16)); 26 fAlphaType = (SkAlphaType)((packed >> 8) & 0xFF); 27 fColorType = (SkColorType)((packed >> 0) & 0xFF); 28 buffer.validate(alpha_type_is_valid(fAlphaType) && 29 color_type_is_valid(fColorType)); 30 } 31 32 void SkImageInfo::flatten(SkWriteBuffer& buffer) const { 33 buffer.write32(fWidth); 34 buffer.write32(fHeight); 35 36 SkASSERT(0 == (fAlphaType & ~0xFF)); 37 SkASSERT(0 == (fColorType & ~0xFF)); 38 uint32_t packed = (fAlphaType << 8) | fColorType; 39 buffer.write32(packed); 40 } 41 42 bool SkColorTypeValidateAlphaType(SkColorType colorType, SkAlphaType alphaType, 43 SkAlphaType* canonical) { 44 switch (colorType) { 45 case kUnknown_SkColorType: 46 alphaType = kIgnore_SkAlphaType; 47 break; 48 case kAlpha_8_SkColorType: 49 if (kUnpremul_SkAlphaType == alphaType) { 50 alphaType = kPremul_SkAlphaType; 51 } 52 // fall-through 53 case kIndex_8_SkColorType: 54 case kARGB_4444_SkColorType: 55 case kRGBA_8888_SkColorType: 56 case kBGRA_8888_SkColorType: 57 if (kIgnore_SkAlphaType == alphaType) { 58 return false; 59 } 60 break; 61 case kRGB_565_SkColorType: 62 alphaType = kOpaque_SkAlphaType; 63 break; 64 default: 65 return false; 66 } 67 if (canonical) { 68 *canonical = alphaType; 69 } 70 return true; 71 } 72
