1 /* 2 * Copyright 2012 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 #ifndef GrTextureAccess_DEFINED 9 #define GrTextureAccess_DEFINED 10 11 #include "GrGpuResourceRef.h" 12 #include "GrTexture.h" 13 #include "SkRefCnt.h" 14 #include "SkShader.h" 15 16 /** 17 * Represents the filtering and tile modes used to access a texture. It is mostly used with 18 * GrTextureAccess (defined below). Also, some of the texture cache methods require knowledge about 19 * filtering and tiling to perform a cache lookup. If it wasn't for this latter usage this would 20 * be folded into GrTextureAccess. The default is clamp tile modes and no filtering. 21 */ 22 class GrTextureParams { 23 public: 24 GrTextureParams() { 25 this->reset(); 26 } 27 28 enum FilterMode { 29 kNone_FilterMode, 30 kBilerp_FilterMode, 31 kMipMap_FilterMode 32 }; 33 34 GrTextureParams(SkShader::TileMode tileXAndY, FilterMode filterMode) { 35 this->reset(tileXAndY, filterMode); 36 } 37 38 GrTextureParams(const SkShader::TileMode tileModes[2], FilterMode filterMode) { 39 this->reset(tileModes, filterMode); 40 } 41 42 GrTextureParams(const GrTextureParams& params) { 43 *this = params; 44 } 45 46 GrTextureParams& operator= (const GrTextureParams& params) { 47 fTileModes[0] = params.fTileModes[0]; 48 fTileModes[1] = params.fTileModes[1]; 49 fFilterMode = params.fFilterMode; 50 return *this; 51 } 52 53 void reset() { 54 this->reset(SkShader::kClamp_TileMode, kNone_FilterMode); 55 } 56 57 void reset(SkShader::TileMode tileXAndY, FilterMode filterMode) { 58 fTileModes[0] = fTileModes[1] = tileXAndY; 59 fFilterMode = filterMode; 60 } 61 62 void reset(const SkShader::TileMode tileModes[2], FilterMode filterMode) { 63 fTileModes[0] = tileModes[0]; 64 fTileModes[1] = tileModes[1]; 65 fFilterMode = filterMode; 66 } 67 68 void setClampNoFilter() { 69 fTileModes[0] = fTileModes[1] = SkShader::kClamp_TileMode; 70 fFilterMode = kNone_FilterMode; 71 } 72 73 void setClamp() { 74 fTileModes[0] = fTileModes[1] = SkShader::kClamp_TileMode; 75 } 76 77 void setFilterMode(FilterMode filterMode) { fFilterMode = filterMode; } 78 79 void setTileModeX(const SkShader::TileMode tm) { fTileModes[0] = tm; } 80 void setTileModeY(const SkShader::TileMode tm) { fTileModes[1] = tm; } 81 void setTileModeXAndY(const SkShader::TileMode tm) { fTileModes[0] = fTileModes[1] = tm; } 82 83 SkShader::TileMode getTileModeX() const { return fTileModes[0]; } 84 85 SkShader::TileMode getTileModeY() const { return fTileModes[1]; } 86 87 bool isTiled() const { 88 return SkShader::kClamp_TileMode != fTileModes[0] || 89 SkShader::kClamp_TileMode != fTileModes[1]; 90 } 91 92 FilterMode filterMode() const { return fFilterMode; } 93 94 bool operator== (const GrTextureParams& other) const { 95 return fTileModes[0] == other.fTileModes[0] && 96 fTileModes[1] == other.fTileModes[1] && 97 fFilterMode == other.fFilterMode; 98 } 99 100 bool operator!= (const GrTextureParams& other) const { return !(*this == other); } 101 102 private: 103 104 SkShader::TileMode fTileModes[2]; 105 FilterMode fFilterMode; 106 }; 107 108 /** A class representing the swizzle access pattern for a texture. Note that if the texture is 109 * an alpha-only texture then the alpha channel is substituted for other components. Any mangling 110 * to handle the r,g,b->a conversions for alpha textures is automatically included in the stage 111 * key. However, if a GrProcessor uses different swizzles based on its input then it must 112 * consider that variation in its key-generation. 113 */ 114 class GrTextureAccess : public SkNoncopyable { 115 public: 116 SK_DECLARE_INST_COUNT(GrTextureAccess); 117 118 /** 119 * A default GrTextureAccess must have reset() called on it in a GrProcessor subclass's 120 * constructor if it will be accessible via GrProcessor::textureAccess(). 121 */ 122 GrTextureAccess(); 123 124 /** 125 * Uses the default swizzle, "rgba". 126 */ 127 GrTextureAccess(GrTexture*, const GrTextureParams&); 128 explicit GrTextureAccess(GrTexture*, 129 GrTextureParams::FilterMode = GrTextureParams::kNone_FilterMode, 130 SkShader::TileMode tileXAndY = SkShader::kClamp_TileMode); 131 132 /** 133 * swizzle must be a string between one and four (inclusive) characters containing only 'r', 134 * 'g', 'b', and/or 'a'. 135 */ 136 GrTextureAccess(GrTexture*, const char* swizzle, const GrTextureParams&); 137 GrTextureAccess(GrTexture*, 138 const char* swizzle, 139 GrTextureParams::FilterMode = GrTextureParams::kNone_FilterMode, 140 SkShader::TileMode tileXAndY = SkShader::kClamp_TileMode); 141 142 void reset(GrTexture*, const GrTextureParams&); 143 void reset(GrTexture*, 144 GrTextureParams::FilterMode = GrTextureParams::kNone_FilterMode, 145 SkShader::TileMode tileXAndY = SkShader::kClamp_TileMode); 146 void reset(GrTexture*, const char* swizzle, const GrTextureParams&); 147 void reset(GrTexture*, 148 const char* swizzle, 149 GrTextureParams::FilterMode = GrTextureParams::kNone_FilterMode, 150 SkShader::TileMode tileXAndY = SkShader::kClamp_TileMode); 151 152 bool operator== (const GrTextureAccess& other) const { 153 #ifdef SK_DEBUG 154 // below assumes all chars in fSwizzle are initialized even if string is < 4 chars long. 155 SkASSERT(memcmp(fSwizzle, other.fSwizzle, sizeof(fSwizzle)-1) == 156 strcmp(fSwizzle, other.fSwizzle)); 157 #endif 158 return fParams == other.fParams && 159 (this->getTexture() == other.getTexture()) && 160 (0 == memcmp(fSwizzle, other.fSwizzle, sizeof(fSwizzle)-1)); 161 } 162 163 bool operator!= (const GrTextureAccess& other) const { return !(*this == other); } 164 165 GrTexture* getTexture() const { return fTexture.get(); } 166 167 /** 168 * For internal use by GrProcessor. 169 */ 170 const GrGpuResourceRef* getProgramTexture() const { return &fTexture; } 171 172 /** 173 * Returns a string representing the swizzle. The string is is null-terminated. 174 */ 175 const char* getSwizzle() const { return fSwizzle; } 176 177 /** Returns a mask indicating which components are referenced in the swizzle. The return 178 is a bitfield of GrColorComponentFlags. */ 179 uint32_t swizzleMask() const { return fSwizzleMask; } 180 181 const GrTextureParams& getParams() const { return fParams; } 182 183 private: 184 void setSwizzle(const char*); 185 186 typedef GrTGpuResourceRef<GrTexture> ProgramTexture; 187 188 ProgramTexture fTexture; 189 GrTextureParams fParams; 190 uint32_t fSwizzleMask; 191 char fSwizzle[5]; 192 193 typedef SkNoncopyable INHERITED; 194 }; 195 196 #endif 197
