1 /* 2 * Copyright 2006 The Android Open Source Project 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 SkGradientShader_DEFINED 9 #define SkGradientShader_DEFINED 10 11 #include "SkShader.h" 12 13 /** \class SkGradientShader 14 15 SkGradientShader hosts factories for creating subclasses of SkShader that 16 render linear and radial gradients. 17 */ 18 class SK_API SkGradientShader { 19 public: 20 enum Flags { 21 /** By default gradients will interpolate their colors in unpremul space 22 * and then premultiply each of the results. By setting this flag, the 23 * gradients will premultiply their colors first, and then interpolate 24 * between them. 25 */ 26 kInterpolateColorsInPremul_Flag = 1 << 0, 27 }; 28 29 /** Returns a shader that generates a linear gradient between the two specified points. 30 <p /> 31 @param pts The start and end points for the gradient. 32 @param colors The array[count] of colors, to be distributed between the two points 33 @param pos May be NULL. array[count] of SkScalars, or NULL, of the relative position of 34 each corresponding color in the colors array. If this is NULL, 35 the the colors are distributed evenly between the start and end point. 36 If this is not null, the values must begin with 0, end with 1.0, and 37 intermediate values must be strictly increasing. 38 @param count Must be >=2. The number of colors (and pos if not NULL) entries. 39 @param mode The tiling mode 40 */ 41 static sk_sp<SkShader> MakeLinear(const SkPoint pts[2], 42 const SkColor colors[], const SkScalar pos[], int count, 43 SkShader::TileMode mode, 44 uint32_t flags, const SkMatrix* localMatrix); 45 static sk_sp<SkShader> MakeLinear(const SkPoint pts[2], 46 const SkColor colors[], const SkScalar pos[], int count, 47 SkShader::TileMode mode) { 48 return MakeLinear(pts, colors, pos, count, mode, 0, NULL); 49 } 50 51 /** Returns a shader that generates a linear gradient between the two specified points. 52 <p /> 53 @param pts The start and end points for the gradient. 54 @param colors The array[count] of colors, to be distributed between the two points 55 @param pos May be NULL. array[count] of SkScalars, or NULL, of the relative position of 56 each corresponding color in the colors array. If this is NULL, 57 the the colors are distributed evenly between the start and end point. 58 If this is not null, the values must begin with 0, end with 1.0, and 59 intermediate values must be strictly increasing. 60 @param count Must be >=2. The number of colors (and pos if not NULL) entries. 61 @param mode The tiling mode 62 */ 63 static sk_sp<SkShader> MakeLinear(const SkPoint pts[2], 64 const SkColor4f colors[], sk_sp<SkColorSpace> colorSpace, 65 const SkScalar pos[], int count, SkShader::TileMode mode, 66 uint32_t flags, const SkMatrix* localMatrix); 67 static sk_sp<SkShader> MakeLinear(const SkPoint pts[2], 68 const SkColor4f colors[], sk_sp<SkColorSpace> colorSpace, 69 const SkScalar pos[], int count, SkShader::TileMode mode) { 70 return MakeLinear(pts, colors, std::move(colorSpace), pos, count, mode, 0, NULL); 71 } 72 73 /** Returns a shader that generates a radial gradient given the center and radius. 74 <p /> 75 @param center The center of the circle for this gradient 76 @param radius Must be positive. The radius of the circle for this gradient 77 @param colors The array[count] of colors, to be distributed between the center and edge of the circle 78 @param pos May be NULL. The array[count] of SkScalars, or NULL, of the relative position of 79 each corresponding color in the colors array. If this is NULL, 80 the the colors are distributed evenly between the center and edge of the circle. 81 If this is not null, the values must begin with 0, end with 1.0, and 82 intermediate values must be strictly increasing. 83 @param count Must be >= 2. The number of colors (and pos if not NULL) entries 84 @param mode The tiling mode 85 */ 86 static sk_sp<SkShader> MakeRadial(const SkPoint& center, SkScalar radius, 87 const SkColor colors[], const SkScalar pos[], int count, 88 SkShader::TileMode mode, 89 uint32_t flags, const SkMatrix* localMatrix); 90 static sk_sp<SkShader> MakeRadial(const SkPoint& center, SkScalar radius, 91 const SkColor colors[], const SkScalar pos[], int count, 92 SkShader::TileMode mode) { 93 return MakeRadial(center, radius, colors, pos, count, mode, 0, NULL); 94 } 95 96 /** Returns a shader that generates a radial gradient given the center and radius. 97 <p /> 98 @param center The center of the circle for this gradient 99 @param radius Must be positive. The radius of the circle for this gradient 100 @param colors The array[count] of colors, to be distributed between the center and edge of the circle 101 @param pos May be NULL. The array[count] of SkScalars, or NULL, of the relative position of 102 each corresponding color in the colors array. If this is NULL, 103 the the colors are distributed evenly between the center and edge of the circle. 104 If this is not null, the values must begin with 0, end with 1.0, and 105 intermediate values must be strictly increasing. 106 @param count Must be >= 2. The number of colors (and pos if not NULL) entries 107 @param mode The tiling mode 108 */ 109 static sk_sp<SkShader> MakeRadial(const SkPoint& center, SkScalar radius, 110 const SkColor4f colors[], sk_sp<SkColorSpace> colorSpace, 111 const SkScalar pos[], int count, SkShader::TileMode mode, 112 uint32_t flags, const SkMatrix* localMatrix); 113 static sk_sp<SkShader> MakeRadial(const SkPoint& center, SkScalar radius, 114 const SkColor4f colors[], sk_sp<SkColorSpace> colorSpace, 115 const SkScalar pos[], int count, SkShader::TileMode mode) { 116 return MakeRadial(center, radius, colors, std::move(colorSpace), pos, count, mode, 0, NULL); 117 } 118 119 /** 120 * Returns a shader that generates a conical gradient given two circles, or 121 * returns NULL if the inputs are invalid. The gradient interprets the 122 * two circles according to the following HTML spec. 123 * http://dev.w3.org/html5/2dcontext/#dom-context-2d-createradialgradient 124 */ 125 static sk_sp<SkShader> MakeTwoPointConical(const SkPoint& start, SkScalar startRadius, 126 const SkPoint& end, SkScalar endRadius, 127 const SkColor colors[], const SkScalar pos[], 128 int count, SkShader::TileMode mode, 129 uint32_t flags, const SkMatrix* localMatrix); 130 static sk_sp<SkShader> MakeTwoPointConical(const SkPoint& start, SkScalar startRadius, 131 const SkPoint& end, SkScalar endRadius, 132 const SkColor colors[], const SkScalar pos[], 133 int count, SkShader::TileMode mode) { 134 return MakeTwoPointConical(start, startRadius, end, endRadius, colors, pos, count, mode, 135 0, NULL); 136 } 137 138 /** 139 * Returns a shader that generates a conical gradient given two circles, or 140 * returns NULL if the inputs are invalid. The gradient interprets the 141 * two circles according to the following HTML spec. 142 * http://dev.w3.org/html5/2dcontext/#dom-context-2d-createradialgradient 143 */ 144 static sk_sp<SkShader> MakeTwoPointConical(const SkPoint& start, SkScalar startRadius, 145 const SkPoint& end, SkScalar endRadius, 146 const SkColor4f colors[], 147 sk_sp<SkColorSpace> colorSpace, const SkScalar pos[], 148 int count, SkShader::TileMode mode, 149 uint32_t flags, const SkMatrix* localMatrix); 150 static sk_sp<SkShader> MakeTwoPointConical(const SkPoint& start, SkScalar startRadius, 151 const SkPoint& end, SkScalar endRadius, 152 const SkColor4f colors[], 153 sk_sp<SkColorSpace> colorSpace, const SkScalar pos[], 154 int count, SkShader::TileMode mode) { 155 return MakeTwoPointConical(start, startRadius, end, endRadius, colors, 156 std::move(colorSpace), pos, count, mode, 0, NULL); 157 } 158 159 /** Returns a shader that generates a sweep gradient given a center. 160 <p /> 161 @param cx The X coordinate of the center of the sweep 162 @param cx The Y coordinate of the center of the sweep 163 @param colors The array[count] of colors, to be distributed around the center. 164 @param pos May be NULL. The array[count] of SkScalars, or NULL, of the relative position of 165 each corresponding color in the colors array. If this is NULL, 166 the the colors are distributed evenly between the center and edge of the circle. 167 If this is not null, the values must begin with 0, end with 1.0, and 168 intermediate values must be strictly increasing. 169 @param count Must be >= 2. The number of colors (and pos if not NULL) entries 170 */ 171 static sk_sp<SkShader> MakeSweep(SkScalar cx, SkScalar cy, 172 const SkColor colors[], const SkScalar pos[], int count, 173 uint32_t flags, const SkMatrix* localMatrix); 174 static sk_sp<SkShader> MakeSweep(SkScalar cx, SkScalar cy, 175 const SkColor colors[], const SkScalar pos[], int count) { 176 return MakeSweep(cx, cy, colors, pos, count, 0, NULL); 177 } 178 179 /** Returns a shader that generates a sweep gradient given a center. 180 <p /> 181 @param cx The X coordinate of the center of the sweep 182 @param cx The Y coordinate of the center of the sweep 183 @param colors The array[count] of colors, to be distributed around the center. 184 @param pos May be NULL. The array[count] of SkScalars, or NULL, of the relative position of 185 each corresponding color in the colors array. If this is NULL, 186 the the colors are distributed evenly between the center and edge of the circle. 187 If this is not null, the values must begin with 0, end with 1.0, and 188 intermediate values must be strictly increasing. 189 @param count Must be >= 2. The number of colors (and pos if not NULL) entries 190 */ 191 static sk_sp<SkShader> MakeSweep(SkScalar cx, SkScalar cy, 192 const SkColor4f colors[], sk_sp<SkColorSpace> colorSpace, 193 const SkScalar pos[], int count, 194 uint32_t flags, const SkMatrix* localMatrix); 195 static sk_sp<SkShader> MakeSweep(SkScalar cx, SkScalar cy, 196 const SkColor4f colors[], sk_sp<SkColorSpace> colorSpace, 197 const SkScalar pos[], int count) { 198 return MakeSweep(cx, cy, colors, std::move(colorSpace), pos, count, 0, NULL); 199 } 200 201 SK_DECLARE_FLATTENABLE_REGISTRAR_GROUP() 202 }; 203 204 #endif 205
