1 /* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 #ifndef PAINT_UTILS_H 17 #define PAINT_UTILS_H 18 19 #include <utils/Blur.h> 20 21 #include <SkColorFilter.h> 22 #include <SkDrawLooper.h> 23 #include <SkShader.h> 24 25 namespace android { 26 namespace uirenderer { 27 28 /** 29 * Utility methods for accessing data within SkPaint, and providing defaults 30 * with optional SkPaint pointers. 31 */ 32 class PaintUtils { 33 public: 34 getFilter(const SkPaint * paint)35 static inline GLenum getFilter(const SkPaint* paint) { 36 if (!paint || paint->getFilterQuality() != kNone_SkFilterQuality) { 37 return GL_LINEAR; 38 } 39 return GL_NEAREST; 40 } 41 isOpaquePaint(const SkPaint * paint)42 static bool isOpaquePaint(const SkPaint* paint) { 43 if (!paint) return true; // default (paintless) behavior is SrcOver, black 44 45 if (paint->getAlpha() != 0xFF 46 || PaintUtils::isBlendedShader(paint->getShader()) 47 || PaintUtils::isBlendedColorFilter(paint->getColorFilter())) { 48 return false; 49 } 50 51 // Only let simple srcOver / src blending modes declare opaque, since behavior is clear. 52 SkBlendMode mode = paint->getBlendMode(); 53 return mode == SkBlendMode::kSrcOver 54 || mode == SkBlendMode::kSrc; 55 } 56 isBlendedShader(const SkShader * shader)57 static bool isBlendedShader(const SkShader* shader) { 58 if (shader == nullptr) { 59 return false; 60 } 61 return !shader->isOpaque(); 62 } 63 isBlendedColorFilter(const SkColorFilter * filter)64 static bool isBlendedColorFilter(const SkColorFilter* filter) { 65 if (filter == nullptr) { 66 return false; 67 } 68 return (filter->getFlags() & SkColorFilter::kAlphaUnchanged_Flag) == 0; 69 } 70 71 struct TextShadow { 72 SkScalar radius; 73 float dx; 74 float dy; 75 SkColor color; 76 }; 77 getTextShadow(const SkPaint * paint,TextShadow * textShadow)78 static inline bool getTextShadow(const SkPaint* paint, TextShadow* textShadow) { 79 SkDrawLooper::BlurShadowRec blur; 80 if (paint && paint->getLooper() && paint->getLooper()->asABlurShadow(&blur)) { 81 if (textShadow) { 82 textShadow->radius = Blur::convertSigmaToRadius(blur.fSigma); 83 textShadow->dx = blur.fOffset.fX; 84 textShadow->dy = blur.fOffset.fY; 85 textShadow->color = blur.fColor; 86 } 87 return true; 88 } 89 return false; 90 } 91 hasTextShadow(const SkPaint * paint)92 static inline bool hasTextShadow(const SkPaint* paint) { 93 return getTextShadow(paint, nullptr); 94 } 95 getBlendModeDirect(const SkPaint * paint)96 static inline SkBlendMode getBlendModeDirect(const SkPaint* paint) { 97 return paint ? paint->getBlendMode() : SkBlendMode::kSrcOver; 98 } 99 getAlphaDirect(const SkPaint * paint)100 static inline int getAlphaDirect(const SkPaint* paint) { 101 return paint ? paint->getAlpha() : 255; 102 } 103 104 }; // class PaintUtils 105 106 } /* namespace uirenderer */ 107 } /* namespace android */ 108 109 #endif /* PAINT_UTILS_H */ 110