Patch.cpp revision 4bb942083a0d4db746adf95349108dd8ef842e32
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 25namespace android { 26namespace uirenderer { 27 28/////////////////////////////////////////////////////////////////////////////// 29// Constructors/destructor 30/////////////////////////////////////////////////////////////////////////////// 31 32Patch::Patch(const uint32_t xCount, const uint32_t yCount, const int8_t emptyQuads) { 33 // 2 triangles per patch, 3 vertices per triangle 34 verticesCount = ((xCount + 1) * (yCount + 1) - emptyQuads) * 2 * 3; 35 vertices = new TextureVertex[verticesCount]; 36} 37 38Patch::~Patch() { 39 delete[] vertices; 40} 41 42/////////////////////////////////////////////////////////////////////////////// 43// Vertices management 44/////////////////////////////////////////////////////////////////////////////// 45 46void Patch::updateVertices(const float bitmapWidth, const float bitmapHeight, 47 float left, float top, float right, float bottom, 48 const int32_t* xDivs, const int32_t* yDivs, 49 const uint32_t width, const uint32_t height, const uint32_t colorKey) { 50 const uint32_t xStretchCount = (width + 1) >> 1; 51 const uint32_t yStretchCount = (height + 1) >> 1; 52 53 float stretchX = 0.0f; 54 float stretchY = 0.0; 55 56 const float meshWidth = right - left; 57 58 if (xStretchCount > 0) { 59 uint32_t stretchSize = 0; 60 for (uint32_t i = 1; i < width; i += 2) { 61 stretchSize += xDivs[i] - xDivs[i - 1]; 62 } 63 const float xStretchTex = stretchSize; 64 const float fixed = bitmapWidth - stretchSize; 65 const float xStretch = right - left - fixed; 66 stretchX = xStretch / xStretchTex; 67 } 68 69 if (yStretchCount > 0) { 70 uint32_t stretchSize = 0; 71 for (uint32_t i = 1; i < height; i += 2) { 72 stretchSize += yDivs[i] - yDivs[i - 1]; 73 } 74 const float yStretchTex = stretchSize; 75 const float fixed = bitmapHeight - stretchSize; 76 const float yStretch = bottom - top - fixed; 77 stretchY = yStretch / yStretchTex; 78 } 79 80 TextureVertex* vertex = vertices; 81 uint32_t quadCount = 0; 82 83 float previousStepY = 0.0f; 84 85 float y1 = 0.0f; 86 float v1 = 0.0f; 87 88 for (uint32_t i = 0; i < height; i++) { 89 float stepY = yDivs[i]; 90 91 float y2 = 0.0f; 92 if (i & 1) { 93 const float segment = stepY - previousStepY; 94 y2 = y1 + segment * stretchY; 95 } else { 96 y2 = y1 + stepY - previousStepY; 97 } 98 float v2 = fmax(0.0f, stepY - 0.5f) / bitmapHeight; 99 100 generateRow(vertex, y1, y2, v1, v2, xDivs, width, stretchX, 101 right - left, bitmapWidth, quadCount, colorKey); 102 103 y1 = y2; 104 v1 = (stepY + 0.5f) / bitmapHeight; 105 106 previousStepY = stepY; 107 } 108 109 generateRow(vertex, y1, bottom - top, v1, 1.0f, xDivs, width, stretchX, 110 right - left, bitmapWidth, quadCount, colorKey); 111} 112 113inline void Patch::generateRow(TextureVertex*& vertex, float y1, float y2, float v1, float v2, 114 const int32_t xDivs[], uint32_t xCount, float stretchX, float width, float bitmapWidth, 115 uint32_t& quadCount, const uint32_t colorKey) { 116 float previousStepX = 0.0f; 117 118 float x1 = 0.0f; 119 float u1 = 0.0f; 120 121 // Generate the row quad by quad 122 for (uint32_t i = 0; i < xCount; i++) { 123 float stepX = xDivs[i]; 124 125 float x2 = 0.0f; 126 if (i & 1) { 127 const float segment = stepX - previousStepX; 128 x2 = x1 + segment * stretchX; 129 } else { 130 x2 = x1 + stepX - previousStepX; 131 } 132 float u2 = fmax(0.0f, stepX - 0.5f) / bitmapWidth; 133 134 generateQuad(vertex, x1, y1, x2, y2, u1, v1, u2, v2, quadCount, colorKey); 135 136 x1 = x2; 137 u1 = (stepX + 0.5f) / bitmapWidth; 138 139 previousStepX = stepX; 140 } 141 142 generateQuad(vertex, x1, y1, width, y2, u1, v1, 1.0f, v2, quadCount, colorKey); 143} 144 145inline void Patch::generateQuad(TextureVertex*& vertex, float x1, float y1, float x2, float y2, 146 float u1, float v1, float u2, float v2, uint32_t& quadCount, const uint32_t colorKey) { 147 if (((colorKey >> quadCount++) & 0x1) == 1) { 148 return; 149 } 150 151 // Left triangle 152 TextureVertex::set(vertex++, x1, y1, u1, v1); 153 TextureVertex::set(vertex++, x2, y1, u2, v1); 154 TextureVertex::set(vertex++, x1, y2, u1, v2); 155 156 // Right triangle 157 TextureVertex::set(vertex++, x1, y2, u1, v2); 158 TextureVertex::set(vertex++, x2, y1, u2, v1); 159 TextureVertex::set(vertex++, x2, y2, u2, v2); 160} 161 162}; // namespace uirenderer 163}; // namespace android 164