Patch.cpp revision a5ef39a21683189e5906c9f252b997f0508e350d 
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 <cmath>
20
21#include <utils/Log.h>
22
23#include "Patch.h"
24#include "Caches.h"
25#include "Properties.h"
26
27namespace android {
28namespace uirenderer {
29
30///////////////////////////////////////////////////////////////////////////////
31// Constructors/destructor
32///////////////////////////////////////////////////////////////////////////////
33
34Patch::Patch(const uint32_t xCount, const uint32_t yCount, const int8_t emptyQuads):
35        mXCount(xCount), mYCount(yCount), mEmptyQuads(emptyQuads) {
36    // Initialized with the maximum number of vertices we will need
37    // 2 triangles per patch, 3 vertices per triangle
38    const int maxVertices = ((xCount + 1) * (yCount + 1) - emptyQuads) * 2 * 3;
39    mVertices = new TextureVertex[maxVertices];
40    mUploaded = false;
41
42    verticesCount = 0;
43    hasEmptyQuads = emptyQuads > 0;
44
45    mColorKey = 0;
46    mXDivs = new int32_t[mXCount];
47    mYDivs = new int32_t[mYCount];
48
49    PATCH_LOGD("    patch: xCount = %d, yCount = %d, emptyQuads = %d, max vertices = %d",
50            xCount, yCount, emptyQuads, maxVertices);
51
52    glGenBuffers(1, &meshBuffer);
53}
54
55Patch::~Patch() {
56    delete[] mVertices;
57    delete[] mXDivs;
58    delete[] mYDivs;
59    glDeleteBuffers(1, &meshBuffer);
60}
61
62///////////////////////////////////////////////////////////////////////////////
63// Patch management
64///////////////////////////////////////////////////////////////////////////////
65
66void Patch::copy(const int32_t* xDivs, const int32_t* yDivs) {
67    memcpy(mXDivs, xDivs, mXCount * sizeof(int32_t));
68    memcpy(mYDivs, yDivs, mYCount * sizeof(int32_t));
69}
70
71void Patch::copy(const int32_t* yDivs) {
72    memcpy(mYDivs, yDivs, mYCount * sizeof(int32_t));
73}
74
75void Patch::updateColorKey(const uint32_t colorKey) {
76    mColorKey = colorKey;
77}
78
79bool Patch::matches(const int32_t* xDivs, const int32_t* yDivs, const uint32_t colorKey) {
80    if (mColorKey != colorKey) {
81        updateColorKey(colorKey);
82        copy(xDivs, yDivs);
83        return false;
84    }
85
86    for (uint32_t i = 0; i < mXCount; i++) {
87        if (mXDivs[i] != xDivs[i]) {
88            // The Y divs may or may not match, copy everything
89            copy(xDivs, yDivs);
90            return false;
91        }
92    }
93
94    for (uint32_t i = 0; i < mYCount; i++) {
95        if (mYDivs[i] != yDivs[i]) {
96            // We know all the X divs match, copy only Y divs
97            copy(yDivs);
98            return false;
99        }
100    }
101
102    return true;
103}
104
105///////////////////////////////////////////////////////////////////////////////
106// Vertices management
107///////////////////////////////////////////////////////////////////////////////
108
109void Patch::updateVertices(const float bitmapWidth, const float bitmapHeight,
110        float left, float top, float right, float bottom) {
111#if RENDER_LAYERS_AS_REGIONS
112    if (hasEmptyQuads) quads.clear();
113#endif
114
115    // Reset the vertices count here, we will count exactly how many
116    // vertices we actually need when generating the quads
117    verticesCount = 0;
118
119    const uint32_t xStretchCount = (mXCount + 1) >> 1;
120    const uint32_t yStretchCount = (mYCount + 1) >> 1;
121
122    float stretchX = 0.0f;
123    float stretchY = 0.0;
124
125    const float meshWidth = right - left;
126
127    if (xStretchCount > 0) {
128        uint32_t stretchSize = 0;
129        for (uint32_t i = 1; i < mXCount; i += 2) {
130            stretchSize += mXDivs[i] - mXDivs[i - 1];
131        }
132        const float xStretchTex = stretchSize;
133        const float fixed = bitmapWidth - stretchSize;
134        const float xStretch = right - left - fixed;
135        stretchX = xStretch / xStretchTex;
136    }
137
138    if (yStretchCount > 0) {
139        uint32_t stretchSize = 0;
140        for (uint32_t i = 1; i < mYCount; i += 2) {
141            stretchSize += mYDivs[i] - mYDivs[i - 1];
142        }
143        const float yStretchTex = stretchSize;
144        const float fixed = bitmapHeight - stretchSize;
145        const float yStretch = bottom - top - fixed;
146        stretchY = yStretch / yStretchTex;
147    }
148
149    TextureVertex* vertex = mVertices;
150    uint32_t quadCount = 0;
151
152    float previousStepY = 0.0f;
153
154    float y1 = 0.0f;
155    float v1 = 0.0f;
156
157    for (uint32_t i = 0; i < mYCount; i++) {
158        float stepY = mYDivs[i];
159
160        float y2 = 0.0f;
161        if (i & 1) {
162            const float segment = stepY - previousStepY;
163            y2 = y1 + segment * stretchY;
164        } else {
165            y2 = y1 + stepY - previousStepY;
166        }
167        float v2 = fmax(0.0f, stepY - 0.5f) / bitmapHeight;
168
169        generateRow(vertex, y1, y2, v1, v2, stretchX, right - left, bitmapWidth, quadCount);
170
171        y1 = y2;
172        v1 = (stepY + 0.5f) / bitmapHeight;
173
174        previousStepY = stepY;
175    }
176
177    generateRow(vertex, y1, bottom - top, v1, 1.0f, stretchX, right - left,
178            bitmapWidth, quadCount);
179
180    if (verticesCount > 0) {
181        Caches::getInstance().bindMeshBuffer(meshBuffer);
182        if (!mUploaded) {
183            glBufferData(GL_ARRAY_BUFFER, sizeof(TextureVertex) * verticesCount,
184                    mVertices, GL_DYNAMIC_DRAW);
185            mUploaded = true;
186        } else {
187            glBufferSubData(GL_ARRAY_BUFFER, 0,
188                    sizeof(TextureVertex) * verticesCount, mVertices);
189        }
190    }
191
192    PATCH_LOGD("    patch: new vertices count = %d", verticesCount);
193}
194
195void Patch::generateRow(TextureVertex*& vertex, float y1, float y2, float v1, float v2,
196        float stretchX, float width, float bitmapWidth, uint32_t& quadCount) {
197    float previousStepX = 0.0f;
198
199    float x1 = 0.0f;
200    float u1 = 0.0f;
201
202    // Generate the row quad by quad
203    for (uint32_t i = 0; i < mXCount; i++) {
204        float stepX = mXDivs[i];
205
206        float x2 = 0.0f;
207        if (i & 1) {
208            const float segment = stepX - previousStepX;
209            x2 = x1 + segment * stretchX;
210        } else {
211            x2 = x1 + stepX - previousStepX;
212        }
213        float u2 = fmax(0.0f, stepX - 0.5f) / bitmapWidth;
214
215        generateQuad(vertex, x1, y1, x2, y2, u1, v1, u2, v2, quadCount);
216
217        x1 = x2;
218        u1 = (stepX + 0.5f) / bitmapWidth;
219
220        previousStepX = stepX;
221    }
222
223    generateQuad(vertex, x1, y1, width, y2, u1, v1, 1.0f, v2, quadCount);
224}
225
226void Patch::generateQuad(TextureVertex*& vertex, float x1, float y1, float x2, float y2,
227            float u1, float v1, float u2, float v2, uint32_t& quadCount) {
228    const uint32_t oldQuadCount = quadCount;
229    const bool valid = fabs(x2 - x1) > 0.9999f && fabs(y2 - y1) > 0.9999f;
230    if (valid) {
231        quadCount++;
232    }
233
234    // Skip degenerate and transparent (empty) quads
235    if (!valid || ((mColorKey >> oldQuadCount) & 0x1) == 1) {
236        return;
237    }
238
239#if RENDER_LAYERS_AS_REGIONS
240    // Record all non empty quads
241    if (hasEmptyQuads) {
242        Rect bounds(x1, y1, x2, y2);
243        quads.add(bounds);
244    }
245#endif
246
247    // Left triangle
248    TextureVertex::set(vertex++, x1, y1, u1, v1);
249    TextureVertex::set(vertex++, x2, y1, u2, v1);
250    TextureVertex::set(vertex++, x1, y2, u1, v2);
251
252    // Right triangle
253    TextureVertex::set(vertex++, x1, y2, u1, v2);
254    TextureVertex::set(vertex++, x2, y1, u2, v1);
255    TextureVertex::set(vertex++, x2, y2, u2, v2);
256
257    // A quad is made of 2 triangles, 6 vertices
258    verticesCount += 6;
259
260#if DEBUG_PATCHES_VERTICES
261    PATCH_LOGD("    quad %d", oldQuadCount);
262    PATCH_LOGD("        left,  top    = %.2f, %.2f\t\tu1, v1 = %.2f, %.2f", x1, y1, u1, v1);
263    PATCH_LOGD("        right, bottom = %.2f, %.2f\t\tu2, v2 = %.2f, %.2f", x2, y2, u2, v2);
264#endif
265}
266
267}; // namespace uirenderer
268}; // namespace android
269