1a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich/* 2c086ca1fa7cebc3e9a51abd4be4688346225c2e4Dan Bornstein * Copyright (C) 2009 The Android Open Source Project 3a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 4a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Licensed under the Apache License, Version 2.0 (the "License"); 5a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * you may not use this file except in compliance with the License. 6a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * You may obtain a copy of the License at 7a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 8c086ca1fa7cebc3e9a51abd4be4688346225c2e4Dan Bornstein * http://www.apache.org/licenses/LICENSE-2.0 9a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 10a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Unless required by applicable law or agreed to in writing, software 11a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * distributed under the License is distributed on an "AS IS" BASIS, 12a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * See the License for the specific language governing permissions and 14a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * limitations under the License. 15a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 16a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 17a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevichpackage android.opengl; 18a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 19a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevichimport java.nio.Buffer; 20a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 21a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich/** 22a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Methods for encoding and decoding ETC1 textures. 23a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * <p> 24a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * The standard for the ETC1 texture format can be found at 25a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * http://www.khronos.org/registry/gles/extensions/OES/OES_compressed_ETC1_RGB8_texture.txt 26a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * <p> 27a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * The PKM file format is of a 16-byte header that describes the image bounds 28a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * followed by the encoded ETC1 texture data. 29a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * <p> 308af9649d44745adba8be4db4e96af053ba32f2c5Jack Palevich * @see ETC1Util 31a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 32a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevichpublic class ETC1 { 33a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 34a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 35a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Size in bytes of an encoded block. 36a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 37a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static final int ENCODED_BLOCK_SIZE = 8; 38a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 39a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 40a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Size in bytes of a decoded block. 41a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 42a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static final int DECODED_BLOCK_SIZE = 48; 43a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 44a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 45a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Size of a PKM file header, in bytes. 46a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 47a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static final int ETC_PKM_HEADER_SIZE = 16; 48a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 49a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 50a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Accepted by the internalformat parameter of glCompressedTexImage2D. 51a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 52a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static final int ETC1_RGB8_OES = 0x8D64; 53a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 54a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 55a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Encode a block of pixels. 56a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 57a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param in a native order direct buffer of size DECODED_BLOCK_SIZE that represent a 58a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 4 x 4 square of 3-byte pixels in form R, G, B. Byte (3 * (x + 4 * y) is the R 59a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * value of pixel (x, y). 60a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 61a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param validPixelMask is a 16-bit mask where bit (1 << (x + y * 4)) indicates whether 62a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * the corresponding (x,y) pixel is valid. Invalid pixel color values are ignored when compressing. 63a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 64a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param out a native order direct buffer of size ENCODED_BLOCK_SIZE that receives the 65a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * ETC1 compressed version of the data. 66a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 67a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 68a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static native void encodeBlock(Buffer in, int validPixelMask, Buffer out); 69a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 70a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 71a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Decode a block of pixels. 72a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 73a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param in a native order direct buffer of size ENCODED_BLOCK_SIZE that contains the 74a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * ETC1 compressed version of the data. 75a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 76a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param out a native order direct buffer of size DECODED_BLOCK_SIZE that will receive 77a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * the decoded data. The data represents a 78a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 4 x 4 square of 3-byte pixels in form R, G, B. Byte (3 * (x + 4 * y) is the R 79a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * value of pixel (x, y). 80a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 81a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static native void decodeBlock(Buffer in, Buffer out); 82a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 83a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 84a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Return the size of the encoded image data (does not include size of PKM header). 85a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 86a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static native int getEncodedDataSize(int width, int height); 87a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 88a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 89a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Encode an entire image. 90a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param in a native order direct buffer of the image data. Formatted such that 91a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * pixel (x,y) is at pIn + pixelSize * x + stride * y; 92a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param out a native order direct buffer of the encoded data. 93a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Must be large enough to store entire encoded image. 94a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param pixelSize must be 2 or 3. 2 is an GL_UNSIGNED_SHORT_5_6_5 image, 95a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 3 is a GL_BYTE RGB image. 96a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 97a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static native void encodeImage(Buffer in, int width, int height, 98a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich int pixelSize, int stride, Buffer out); 99a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 100a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 101a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Decode an entire image. 102a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param in native order direct buffer of the encoded data. 103a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param out native order direct buffer of the image data. Will be written such that 104a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * pixel (x,y) is at pIn + pixelSize * x + stride * y. Must be 105a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * large enough to store entire image. 106a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param pixelSize must be 2 or 3. 2 is an GL_UNSIGNED_SHORT_5_6_5 image, 107a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * 3 is a GL_BYTE RGB image. 108a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 109a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static native void decodeImage(Buffer in, Buffer out, 110a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich int width, int height, int pixelSize, int stride); 111a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 112a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 113a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Format a PKM header 114a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param header native order direct buffer of the header. 115a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param width the width of the image in pixels. 116a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param height the height of the image in pixels. 117a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 118a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static native void formatHeader(Buffer header, int width, int height); 119a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 120a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 121a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Check if a PKM header is correctly formatted. 122a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param header native order direct buffer of the header. 123a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 124a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static native boolean isValid(Buffer header); 125a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 126a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 127a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Read the image width from a PKM header 128a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param header native order direct buffer of the header. 129a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 130a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static native int getWidth(Buffer header); 131a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich 132a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich /** 133a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * Read the image height from a PKM header 134a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich * @param header native order direct buffer of the header. 135a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich */ 136a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich public static native int getHeight(Buffer header); 137a6276fdd4253c3a7150ab675678c750473ab6c45Jack Palevich} 138