1 /* 2 * libjingle 3 * Copyright 2015 Google Inc. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, 9 * this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 19 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 package org.webrtc; 29 30 import android.opengl.GLES20; 31 32 /** 33 * Helper class for handling OpenGL framebuffer with only color attachment and no depth or stencil 34 * buffer. Intended for simple tasks such as texture copy, texture downscaling, and texture color 35 * conversion. 36 */ 37 // TODO(magjed): Add unittests for this class. 38 public class GlTextureFrameBuffer { 39 private final int frameBufferId; 40 private final int textureId; 41 private final int pixelFormat; 42 private int width; 43 private int height; 44 45 /** 46 * Generate texture and framebuffer resources. An EGLContext must be bound on the current thread 47 * when calling this function. The framebuffer is not complete until setSize() is called. 48 */ GlTextureFrameBuffer(int pixelFormat)49 public GlTextureFrameBuffer(int pixelFormat) { 50 switch (pixelFormat) { 51 case GLES20.GL_LUMINANCE: 52 case GLES20.GL_RGB: 53 case GLES20.GL_RGBA: 54 this.pixelFormat = pixelFormat; 55 break; 56 default: 57 throw new IllegalArgumentException("Invalid pixel format: " + pixelFormat); 58 } 59 60 textureId = GlUtil.generateTexture(GLES20.GL_TEXTURE_2D); 61 this.width = 0; 62 this.height = 0; 63 64 // Create framebuffer object and bind it. 65 final int frameBuffers[] = new int[1]; 66 GLES20.glGenFramebuffers(1, frameBuffers, 0); 67 frameBufferId = frameBuffers[0]; 68 GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, frameBufferId); 69 GlUtil.checkNoGLES2Error("Generate framebuffer"); 70 71 // Attach the texture to the framebuffer as color attachment. 72 GLES20.glFramebufferTexture2D(GLES20.GL_FRAMEBUFFER, GLES20.GL_COLOR_ATTACHMENT0, 73 GLES20.GL_TEXTURE_2D, textureId, 0); 74 GlUtil.checkNoGLES2Error("Attach texture to framebuffer"); 75 76 // Restore normal framebuffer. 77 GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0); 78 } 79 80 /** 81 * (Re)allocate texture. Will do nothing if the requested size equals the current size. An 82 * EGLContext must be bound on the current thread when calling this function. Must be called at 83 * least once before using the framebuffer. May be called multiple times to change size. 84 */ setSize(int width, int height)85 public void setSize(int width, int height) { 86 if (width == 0 || height == 0) { 87 throw new IllegalArgumentException("Invalid size: " + width + "x" + height); 88 } 89 if (width == this.width && height == this.height) { 90 return; 91 } 92 this.width = width; 93 this.height = height; 94 95 // Bind our framebuffer. 96 GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, frameBufferId); 97 GlUtil.checkNoGLES2Error("glBindFramebuffer"); 98 99 // Allocate texture. 100 GLES20.glActiveTexture(GLES20.GL_TEXTURE0); 101 GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureId); 102 GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, pixelFormat, width, height, 0, pixelFormat, 103 GLES20.GL_UNSIGNED_BYTE, null); 104 105 // Check that the framebuffer is in a good state. 106 final int status = GLES20.glCheckFramebufferStatus(GLES20.GL_FRAMEBUFFER); 107 if (status != GLES20.GL_FRAMEBUFFER_COMPLETE) { 108 throw new IllegalStateException("Framebuffer not complete, status: " + status); 109 } 110 111 // Restore normal framebuffer. 112 GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0); 113 GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, 0); 114 } 115 getWidth()116 public int getWidth() { 117 return width; 118 } 119 getHeight()120 public int getHeight() { 121 return height; 122 } 123 getFrameBufferId()124 public int getFrameBufferId() { 125 return frameBufferId; 126 } 127 getTextureId()128 public int getTextureId() { 129 return textureId; 130 } 131 132 /** 133 * Release texture and framebuffer. An EGLContext must be bound on the current thread when calling 134 * this function. This object should not be used after this call. 135 */ release()136 public void release() { 137 GLES20.glDeleteTextures(1, new int[] {textureId}, 0); 138 GLES20.glDeleteFramebuffers(1, new int[] {frameBufferId}, 0); 139 width = 0; 140 height = 0; 141 } 142 } 143