SkiaColorFilter.cpp revision 6ed9e43879039ce0cbead08d304edbce79a88ced 
1/*
2 * Copyright (C) 2010 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
17#include "SkiaColorFilter.h"
18
19namespace android {
20namespace uirenderer {
21
22///////////////////////////////////////////////////////////////////////////////
23// Base color filter
24///////////////////////////////////////////////////////////////////////////////
25
26SkiaColorFilter::SkiaColorFilter(SkColorFilter *skFilter, Type type, bool blend):
27        mType(type), mBlend(blend), mSkFilter(skFilter) {
28}
29
30SkiaColorFilter::~SkiaColorFilter() {
31}
32
33///////////////////////////////////////////////////////////////////////////////
34// Color matrix filter
35///////////////////////////////////////////////////////////////////////////////
36
37SkiaColorMatrixFilter::SkiaColorMatrixFilter(SkColorFilter* skFilter, float* matrix, float* vector):
38        SkiaColorFilter(skFilter, kColorMatrix, true), mMatrix(matrix), mVector(vector) {
39    // Skia uses the range [0..255] for the addition vector, but we need
40    // the [0..1] range to apply the vector in GLSL
41    for (int i = 0; i < 4; i++) {
42        mVector[i] /= 255.0f;
43    }
44
45    // TODO: We should be smarter about this
46    mBlend = true;
47}
48
49SkiaColorMatrixFilter::~SkiaColorMatrixFilter() {
50    delete[] mMatrix;
51    delete[] mVector;
52}
53
54void SkiaColorMatrixFilter::describe(ProgramDescription& description,
55        const Extensions& extensions) {
56    description.colorOp = ProgramDescription::kColorMatrix;
57}
58
59void SkiaColorMatrixFilter::setupProgram(Program* program) {
60    glUniformMatrix4fv(program->getUniform("colorMatrix"), 1, GL_FALSE, &mMatrix[0]);
61    glUniform4fv(program->getUniform("colorMatrixVector"), 1, mVector);
62}
63
64///////////////////////////////////////////////////////////////////////////////
65// Lighting color filter
66///////////////////////////////////////////////////////////////////////////////
67
68SkiaLightingFilter::SkiaLightingFilter(SkColorFilter* skFilter, int multiply, int add):
69        SkiaColorFilter(skFilter, kLighting, true) {
70    mMulR = ((multiply >> 16) & 0xFF) / 255.0f;
71    mMulG = ((multiply >>  8) & 0xFF) / 255.0f;
72    mMulB = ((multiply      ) & 0xFF) / 255.0f;
73
74    mAddR = ((add >> 16) & 0xFF) / 255.0f;
75    mAddG = ((add >>  8) & 0xFF) / 255.0f;
76    mAddB = ((add      ) & 0xFF) / 255.0f;
77
78    // A lighting filter always ignores alpha
79    mBlend = false;
80}
81
82void SkiaLightingFilter::describe(ProgramDescription& description, const Extensions& extensions) {
83    description.colorOp = ProgramDescription::kColorLighting;
84}
85
86void SkiaLightingFilter::setupProgram(Program* program) {
87    glUniform4f(program->getUniform("lightingMul"), mMulR, mMulG, mMulB, 1.0f);
88    glUniform4f(program->getUniform("lightingAdd"), mAddR, mAddG, mAddB, 0.0f);
89}
90
91///////////////////////////////////////////////////////////////////////////////
92// Blend color filter
93///////////////////////////////////////////////////////////////////////////////
94
95SkiaBlendFilter::SkiaBlendFilter(SkColorFilter* skFilter, int color, SkXfermode::Mode mode):
96        SkiaColorFilter(skFilter, kBlend, true), mMode(mode) {
97    const int alpha = (color >> 24) & 0xFF;
98    mA = alpha / 255.0f;
99    mR = mA * ((color >> 16) & 0xFF) / 255.0f;
100    mG = mA * ((color >>  8) & 0xFF) / 255.0f;
101    mB = mA * ((color      ) & 0xFF) / 255.0f;
102
103    // TODO: We should do something smarter here
104    mBlend = true;
105}
106
107void SkiaBlendFilter::describe(ProgramDescription& description, const Extensions& extensions) {
108    description.colorOp = ProgramDescription::kColorBlend;
109    description.colorMode = mMode;
110}
111
112void SkiaBlendFilter::setupProgram(Program* program) {
113    glUniform4f(program->getUniform("colorBlend"), mR, mG, mB, mA);
114}
115
116}; // namespace uirenderer
117}; // namespace android
118