Program.cpp revision 889f8d1403761d5668115ced6cbb3f767cfe966d 
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// Shaders
26///////////////////////////////////////////////////////////////////////////////
27
28#define SHADER_SOURCE(name, source) const char* name = #source
29
30///////////////////////////////////////////////////////////////////////////////
31// Base program
32///////////////////////////////////////////////////////////////////////////////
33
34Program::Program(const char* vertex, const char* fragment) {
35    vertexShader = buildShader(vertex, GL_VERTEX_SHADER);
36    fragmentShader = buildShader(fragment, GL_FRAGMENT_SHADER);
37
38    id = glCreateProgram();
39    glAttachShader(id, vertexShader);
40    glAttachShader(id, fragmentShader);
41    glLinkProgram(id);
42
43    GLint status;
44    glGetProgramiv(id, GL_LINK_STATUS, &status);
45    if (status != GL_TRUE) {
46        GLint infoLen = 0;
47        glGetProgramiv(id, GL_INFO_LOG_LENGTH, &infoLen);
48        if (infoLen > 1) {
49            char* log = (char*) malloc(sizeof(char) * infoLen);
50            glGetProgramInfoLog(id, infoLen, 0, log);
51            LOGE("Error while linking shaders: %s", log);
52            delete log;
53        }
54        glDeleteProgram(id);
55    }
56
57    mUse = false;
58
59    position = addAttrib("position");
60    color = addUniform("color");
61    transform = addUniform("transform");
62}
63
64Program::~Program() {
65    glDeleteShader(vertexShader);
66    glDeleteShader(fragmentShader);
67    glDeleteProgram(id);
68}
69
70int Program::addAttrib(const char* name) {
71    int slot = glGetAttribLocation(id, name);
72    attributes.add(name, slot);
73    return slot;
74}
75
76int Program::getAttrib(const char* name) {
77    ssize_t index = attributes.indexOfKey(name);
78    if (index >= 0) {
79        return attributes.valueAt(index);
80    }
81    return addAttrib(name);
82}
83
84int Program::addUniform(const char* name) {
85    int slot = glGetUniformLocation(id, name);
86    uniforms.add(name, slot);
87    return slot;
88}
89
90int Program::getUniform(const char* name) {
91    ssize_t index = uniforms.indexOfKey(name);
92    if (index >= 0) {
93        return uniforms.valueAt(index);
94    }
95    return addUniform(name);
96}
97
98GLuint Program::buildShader(const char* source, GLenum type) {
99    GLuint shader = glCreateShader(type);
100    glShaderSource(shader, 1, &source, 0);
101    glCompileShader(shader);
102
103    GLint status;
104    glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
105    if (status != GL_TRUE) {
106        // Some drivers return wrong values for GL_INFO_LOG_LENGTH
107        // use a fixed size instead
108        GLchar log[512];
109        glGetShaderInfoLog(shader, sizeof(log), 0, &log[0]);
110        LOGE("Error while compiling shader: %s", log);
111        glDeleteShader(shader);
112    }
113
114    return shader;
115}
116
117void Program::set(const mat4& projectionMatrix, const mat4& modelViewMatrix,
118        const mat4& transformMatrix) {
119    mat4 t(projectionMatrix);
120    t.multiply(transformMatrix);
121    t.multiply(modelViewMatrix);
122
123    glUniformMatrix4fv(transform, 1, GL_FALSE, &t.data[0]);
124}
125
126void Program::use() {
127    glUseProgram(id);
128    mUse = true;
129
130    glEnableVertexAttribArray(position);
131}
132
133void Program::remove() {
134    mUse = false;
135
136    glDisableVertexAttribArray(position);
137}
138
139}; // namespace uirenderer
140}; // namespace android
141