Program.cpp revision 5b3b35296e8b2c8d3f07d32bb645d5414db41a1d 
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#define LOG_TAG "OpenGLRenderer"
18
19#include "Program.h"
20
21namespace android {
22namespace uirenderer {
23
24///////////////////////////////////////////////////////////////////////////////
25// Base program
26///////////////////////////////////////////////////////////////////////////////
27
28Program::Program(const char* vertex, const char* fragment) {
29    vertexShader = buildShader(vertex, GL_VERTEX_SHADER);
30    fragmentShader = buildShader(fragment, GL_FRAGMENT_SHADER);
31
32    id = glCreateProgram();
33    glAttachShader(id, vertexShader);
34    glAttachShader(id, fragmentShader);
35    glLinkProgram(id);
36
37    GLint status;
38    glGetProgramiv(id, GL_LINK_STATUS, &status);
39    if (status != GL_TRUE) {
40        GLint infoLen = 0;
41        glGetProgramiv(id, GL_INFO_LOG_LENGTH, &infoLen);
42        if (infoLen > 1) {
43            GLchar log[infoLen];
44            glGetProgramInfoLog(id, infoLen, 0, &log[0]);
45            LOGE("Error while linking shaders: %s", log);
46        }
47        glDeleteShader(vertexShader);
48        glDeleteShader(fragmentShader);
49        glDeleteProgram(id);
50    }
51
52    mUse = false;
53
54    position = addAttrib("position");
55    transform = addUniform("transform");
56}
57
58Program::~Program() {
59    glDeleteShader(vertexShader);
60    glDeleteShader(fragmentShader);
61    glDeleteProgram(id);
62}
63
64int Program::addAttrib(const char* name) {
65    int slot = glGetAttribLocation(id, name);
66    attributes.add(name, slot);
67    return slot;
68}
69
70int Program::getAttrib(const char* name) {
71    ssize_t index = attributes.indexOfKey(name);
72    if (index >= 0) {
73        return attributes.valueAt(index);
74    }
75    return addAttrib(name);
76}
77
78int Program::addUniform(const char* name) {
79    int slot = glGetUniformLocation(id, name);
80    uniforms.add(name, slot);
81    return slot;
82}
83
84int Program::getUniform(const char* name) {
85    ssize_t index = uniforms.indexOfKey(name);
86    if (index >= 0) {
87        return uniforms.valueAt(index);
88    }
89    return addUniform(name);
90}
91
92GLuint Program::buildShader(const char* source, GLenum type) {
93    GLuint shader = glCreateShader(type);
94    glShaderSource(shader, 1, &source, 0);
95    glCompileShader(shader);
96
97    GLint status;
98    glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
99    if (status != GL_TRUE) {
100        // Some drivers return wrong values for GL_INFO_LOG_LENGTH
101        // use a fixed size instead
102        GLchar log[512];
103        glGetShaderInfoLog(shader, sizeof(log), 0, &log[0]);
104        LOGE("Error while compiling shader: %s", log);
105        glDeleteShader(shader);
106    }
107
108    return shader;
109}
110
111void Program::set(const mat4& projectionMatrix, const mat4& modelViewMatrix,
112        const mat4& transformMatrix) {
113    mat4 t(projectionMatrix);
114    t.multiply(transformMatrix);
115    t.multiply(modelViewMatrix);
116
117    glUniformMatrix4fv(transform, 1, GL_FALSE, &t.data[0]);
118}
119
120void Program::setColor(const float r, const float g, const float b, const float a) {
121    glUniform4f(getUniform("color"), r, g, b, a);
122}
123
124void Program::use() {
125    glUseProgram(id);
126    mUse = true;
127
128    glEnableVertexAttribArray(position);
129}
130
131void Program::remove() {
132    mUse = false;
133
134    glDisableVertexAttribArray(position);
135}
136
137}; // namespace uirenderer
138}; // namespace android
139