SkiaShader.h revision 922d3a7f6f8c1c05a996ee3e91e8cbadfff560c9 
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#ifndef ANDROID_HWUI_SKIA_SHADER_H
18#define ANDROID_HWUI_SKIA_SHADER_H
19
20#include "FloatColor.h"
21#include "Matrix.h"
22
23#include <GLES2/gl2.h>
24#include <SkShader.h>
25#include <SkXfermode.h>
26#include <cutils/compiler.h>
27
28namespace android {
29namespace uirenderer {
30
31class Caches;
32class Extensions;
33class Layer;
34class Texture;
35struct ProgramDescription;
36
37/**
38 * Type of Skia shader in use.
39 *
40 * Note that kBitmap | kGradient = kCompose, since Compose implies
41 * both its component types are in use simultaneously. No other
42 * composition of multiple types is supported.
43 */
44enum SkiaShaderType {
45    kNone_SkiaShaderType = 0,
46    kBitmap_SkiaShaderType = 1,
47    kGradient_SkiaShaderType = 2,
48    kCompose_SkiaShaderType = kBitmap_SkiaShaderType | kGradient_SkiaShaderType,
49    kLayer_SkiaShaderType = 4,
50};
51
52struct SkiaShaderData {
53    SkiaShaderType skiaShaderType;
54    struct BitmapShaderData {
55        Texture* bitmapTexture;
56        GLuint bitmapSampler;
57        GLenum wrapS;
58        GLenum wrapT;
59
60        Matrix4 textureTransform;
61        float textureDimension[2];
62    } bitmapData;
63    struct GradientShaderData {
64        Matrix4 screenSpace;
65        GLuint ditherSampler;
66
67        // simple gradient
68        FloatColor startColor;
69        FloatColor endColor;
70
71        // complex gradient
72        Texture* gradientTexture;
73        GLuint gradientSampler;
74        GLenum wrapST;
75
76    } gradientData;
77    struct LayerShaderData {
78        Layer* layer;
79        GLuint bitmapSampler;
80        GLenum wrapS;
81        GLenum wrapT;
82
83        Matrix4 textureTransform;
84        float textureDimension[2];
85    } layerData;
86};
87
88class SkiaShader {
89public:
90    static SkiaShaderType getType(const SkShader& shader);
91    static void describe(Caches* caches, ProgramDescription& description,
92            const Extensions& extensions, const SkShader& shader);
93    static void setupProgram(Caches* caches, const mat4& modelViewMatrix,
94            GLuint* textureUnit, const Extensions& extensions, const SkShader& shader);
95
96    // new SkiaShader interaction model - store into ShaderData, and apply to Caches/Program/GL
97    static void store(Caches& caches, const SkShader* shader, const Matrix4& modelViewMatrix,
98            GLuint* textureUnit, ProgramDescription* description,
99            SkiaShaderData* outData);
100    static void apply(Caches& caches, const SkiaShaderData& data);
101};
102
103class InvalidSkiaShader {
104public:
105    static void describe(Caches* caches, ProgramDescription& description,
106            const Extensions& extensions, const SkShader& shader) {
107        // This shader is unsupported. Skip it.
108    }
109    static void setupProgram(Caches* caches, const mat4& modelViewMatrix,
110            GLuint* textureUnit, const Extensions& extensions, const SkShader& shader) {
111        // This shader is unsupported. Skip it.
112    }
113
114};
115/**
116 * A shader that draws a layer.
117 */
118class SkiaLayerShader {
119public:
120    static void describe(Caches* caches, ProgramDescription& description,
121            const Extensions& extensions, const SkShader& shader);
122    static void setupProgram(Caches* caches, const mat4& modelViewMatrix,
123            GLuint* textureUnit, const Extensions& extensions, const SkShader& shader);
124}; // class SkiaLayerShader
125
126/**
127 * A shader that draws a bitmap.
128 */
129class SkiaBitmapShader {
130public:
131    static void describe(Caches* caches, ProgramDescription& description,
132            const Extensions& extensions, const SkShader& shader);
133    static void setupProgram(Caches* caches, const mat4& modelViewMatrix,
134            GLuint* textureUnit, const Extensions& extensions, const SkShader& shader);
135
136
137}; // class SkiaBitmapShader
138
139/**
140 * A shader that draws one of three types of gradient, depending on shader param.
141 */
142class SkiaGradientShader {
143public:
144    static void describe(Caches* caches, ProgramDescription& description,
145            const Extensions& extensions, const SkShader& shader);
146    static void setupProgram(Caches* caches, const mat4& modelViewMatrix,
147            GLuint* textureUnit, const Extensions& extensions, const SkShader& shader);
148};
149
150/**
151 * A shader that draws two shaders, composited with an xfermode.
152 */
153class SkiaComposeShader {
154public:
155    static void describe(Caches* caches, ProgramDescription& description,
156            const Extensions& extensions, const SkShader& shader);
157    static void setupProgram(Caches* caches, const mat4& modelViewMatrix,
158            GLuint* textureUnit, const Extensions& extensions, const SkShader& shader);
159}; // class SkiaComposeShader
160
161}; // namespace uirenderer
162}; // namespace android
163
164#endif // ANDROID_HWUI_SKIA_SHADER_H
165