Caches.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 "Caches.h"
20
21namespace android {
22
23#ifdef USE_OPENGL_RENDERER
24using namespace uirenderer;
25ANDROID_SINGLETON_STATIC_INSTANCE(Caches);
26#endif
27
28namespace uirenderer {
29
30///////////////////////////////////////////////////////////////////////////////
31// Constructors/destructor
32///////////////////////////////////////////////////////////////////////////////
33
34Caches::Caches(): Singleton<Caches>(), blend(false), lastSrcMode(GL_ZERO),
35        lastDstMode(GL_ZERO), currentProgram(NULL) {
36    GLint maxTextureUnits;
37    glGetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, &maxTextureUnits);
38    if (maxTextureUnits < REQUIRED_TEXTURE_UNITS_COUNT) {
39        LOGW("At least %d texture units are required!", REQUIRED_TEXTURE_UNITS_COUNT);
40    }
41
42    glGenBuffers(1, &meshBuffer);
43    glBindBuffer(GL_ARRAY_BUFFER, meshBuffer);
44    glBufferData(GL_ARRAY_BUFFER, sizeof(gMeshVertices), gMeshVertices, GL_STATIC_DRAW);
45
46    glGetIntegerv(GL_MAX_TEXTURE_SIZE, &maxTextureSize);
47
48    mCurrentBuffer = meshBuffer;
49    mRegionMesh = NULL;
50}
51
52Caches::~Caches() {
53    delete[] mRegionMesh;
54}
55
56///////////////////////////////////////////////////////////////////////////////
57// VBO
58///////////////////////////////////////////////////////////////////////////////
59
60void Caches::bindMeshBuffer() {
61    bindMeshBuffer(meshBuffer);
62}
63
64void Caches::bindMeshBuffer(const GLuint buffer) {
65    if (mCurrentBuffer != buffer) {
66        glBindBuffer(GL_ARRAY_BUFFER, buffer);
67        mCurrentBuffer = buffer;
68    }
69}
70
71void Caches::unbindMeshBuffer() {
72    if (mCurrentBuffer) {
73        glBindBuffer(GL_ARRAY_BUFFER, 0);
74        mCurrentBuffer = 0;
75    }
76}
77
78TextureVertex* Caches::getRegionMesh() {
79    // Create the mesh, 2 triangles and 4 vertices per rectangle in the region
80    if (!mRegionMesh) {
81        mRegionMesh = new TextureVertex[REGION_MESH_QUAD_COUNT * 4];
82
83        uint16_t* regionIndices = new uint16_t[REGION_MESH_QUAD_COUNT * 6];
84        for (int i = 0; i < REGION_MESH_QUAD_COUNT; i++) {
85            uint16_t quad = i * 4;
86            int index = i * 6;
87            regionIndices[index    ] = quad;       // top-left
88            regionIndices[index + 1] = quad + 1;   // top-right
89            regionIndices[index + 2] = quad + 2;   // bottom-left
90            regionIndices[index + 3] = quad + 2;   // bottom-left
91            regionIndices[index + 4] = quad + 1;   // top-right
92            regionIndices[index + 5] = quad + 3;   // bottom-right
93        }
94
95        glGenBuffers(1, &mRegionMeshIndices);
96        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mRegionMeshIndices);
97        glBufferData(GL_ELEMENT_ARRAY_BUFFER, REGION_MESH_QUAD_COUNT * 6 * sizeof(uint16_t),
98                regionIndices, GL_STATIC_DRAW);
99
100        delete[] regionIndices;
101    } else {
102        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mRegionMeshIndices);
103    }
104
105    return mRegionMesh;
106}
107
108}; // namespace uirenderer
109}; // namespace android
110