1 2/* 3 * Copyright 2011 Google Inc. 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8#include "SkColorMatrix.h" 9 10#define kRScale 0 11#define kGScale 6 12#define kBScale 12 13#define kAScale 18 14 15void SkColorMatrix::setIdentity() { 16 memset(fMat, 0, sizeof(fMat)); 17 fMat[kRScale] = fMat[kGScale] = fMat[kBScale] = fMat[kAScale] = SK_Scalar1; 18} 19 20void SkColorMatrix::setScale(SkScalar rScale, SkScalar gScale, SkScalar bScale, 21 SkScalar aScale) { 22 memset(fMat, 0, sizeof(fMat)); 23 fMat[kRScale] = rScale; 24 fMat[kGScale] = gScale; 25 fMat[kBScale] = bScale; 26 fMat[kAScale] = aScale; 27} 28 29/////////////////////////////////////////////////////////////////////////////// 30 31void SkColorMatrix::setRotate(Axis axis, SkScalar degrees) { 32 SkScalar S, C; 33 34 S = SkScalarSinCos(SkDegreesToRadians(degrees), &C); 35 36 this->setSinCos(axis, S, C); 37} 38 39void SkColorMatrix::setSinCos(Axis axis, SkScalar sine, SkScalar cosine) { 40 SkASSERT((unsigned)axis < 3); 41 42 static const uint8_t gRotateIndex[] = { 43 6, 7, 11, 12, 44 0, 10, 2, 12, 45 0, 1, 5, 6, 46 }; 47 const uint8_t* index = gRotateIndex + axis * 4; 48 49 this->setIdentity(); 50 fMat[index[0]] = cosine; 51 fMat[index[1]] = sine; 52 fMat[index[2]] = -sine; 53 fMat[index[3]] = cosine; 54} 55 56void SkColorMatrix::preRotate(Axis axis, SkScalar degrees) { 57 SkColorMatrix tmp; 58 tmp.setRotate(axis, degrees); 59 this->preConcat(tmp); 60} 61 62void SkColorMatrix::postRotate(Axis axis, SkScalar degrees) { 63 SkColorMatrix tmp; 64 tmp.setRotate(axis, degrees); 65 this->postConcat(tmp); 66} 67 68/////////////////////////////////////////////////////////////////////////////// 69 70void SkColorMatrix::setConcat(const SkColorMatrix& matA, 71 const SkColorMatrix& matB) { 72 SkScalar tmp[20]; 73 SkScalar* result = fMat; 74 75 if (&matA == this || &matB == this) { 76 result = tmp; 77 } 78 79 const SkScalar* a = matA.fMat; 80 const SkScalar* b = matB.fMat; 81 82 int index = 0; 83 for (int j = 0; j < 20; j += 5) { 84 for (int i = 0; i < 4; i++) { 85 result[index++] = SkScalarMul(a[j + 0], b[i + 0]) + 86 SkScalarMul(a[j + 1], b[i + 5]) + 87 SkScalarMul(a[j + 2], b[i + 10]) + 88 SkScalarMul(a[j + 3], b[i + 15]); 89 } 90 result[index++] = SkScalarMul(a[j + 0], b[4]) + 91 SkScalarMul(a[j + 1], b[9]) + 92 SkScalarMul(a[j + 2], b[14]) + 93 SkScalarMul(a[j + 3], b[19]) + 94 a[j + 4]; 95 } 96 97 if (fMat != result) { 98 memcpy(fMat, result, sizeof(fMat)); 99 } 100} 101 102/////////////////////////////////////////////////////////////////////////////// 103 104static void setrow(SkScalar row[], SkScalar r, SkScalar g, SkScalar b) { 105 row[0] = r; 106 row[1] = g; 107 row[2] = b; 108} 109 110static const SkScalar kHueR = SkFloatToScalar(0.213f); 111static const SkScalar kHueG = SkFloatToScalar(0.715f); 112static const SkScalar kHueB = SkFloatToScalar(0.072f); 113 114void SkColorMatrix::setSaturation(SkScalar sat) { 115 memset(fMat, 0, sizeof(fMat)); 116 117 const SkScalar R = SkScalarMul(kHueR, SK_Scalar1 - sat); 118 const SkScalar G = SkScalarMul(kHueG, SK_Scalar1 - sat); 119 const SkScalar B = SkScalarMul(kHueB, SK_Scalar1 - sat); 120 121 setrow(fMat + 0, R + sat, G, B); 122 setrow(fMat + 5, R, G + sat, B); 123 setrow(fMat + 10, R, G, B + sat); 124 fMat[18] = SK_Scalar1; 125} 126 127static const SkScalar kR2Y = SkFloatToScalar(0.299f); 128static const SkScalar kG2Y = SkFloatToScalar(0.587f); 129static const SkScalar kB2Y = SkFloatToScalar(0.114f); 130 131static const SkScalar kR2U = SkFloatToScalar(-0.16874f); 132static const SkScalar kG2U = SkFloatToScalar(-0.33126f); 133static const SkScalar kB2U = SkFloatToScalar(0.5f); 134 135static const SkScalar kR2V = SkFloatToScalar(0.5f); 136static const SkScalar kG2V = SkFloatToScalar(-0.41869f); 137static const SkScalar kB2V = SkFloatToScalar(-0.08131f); 138 139void SkColorMatrix::setRGB2YUV() { 140 memset(fMat, 0, sizeof(fMat)); 141 142 setrow(fMat + 0, kR2Y, kG2Y, kB2Y); 143 setrow(fMat + 5, kR2U, kG2U, kB2U); 144 setrow(fMat + 10, kR2V, kG2V, kB2V); 145 fMat[18] = SK_Scalar1; 146} 147 148static const SkScalar kV2R = SkFloatToScalar(1.402f); 149static const SkScalar kU2G = SkFloatToScalar(-0.34414f); 150static const SkScalar kV2G = SkFloatToScalar(-0.71414f); 151static const SkScalar kU2B = SkFloatToScalar(1.772f); 152 153void SkColorMatrix::setYUV2RGB() { 154 memset(fMat, 0, sizeof(fMat)); 155 156 setrow(fMat + 0, SK_Scalar1, 0, kV2R); 157 setrow(fMat + 5, SK_Scalar1, kU2G, kV2G); 158 setrow(fMat + 10, SK_Scalar1, kU2B, 0); 159 fMat[18] = SK_Scalar1; 160} 161 162