1 /* 2 * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) 3 * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining a 6 * copy of this software and associated documentation files (the "Software"), 7 * to deal in the Software without restriction, including without limitation 8 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 9 * and/or sell copies of the Software, and to permit persons to whom the 10 * Software is furnished to do so, subject to the following conditions: 11 * 12 * The above copyright notice including the dates of first publication and 13 * either this permission notice or a reference to 14 * http://oss.sgi.com/projects/FreeB/ 15 * shall be included in all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 21 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF 22 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 23 * SOFTWARE. 24 * 25 * Except as contained in this notice, the name of Silicon Graphics, Inc. 26 * shall not be used in advertising or otherwise to promote the sale, use or 27 * other dealings in this Software without prior written authorization from 28 * Silicon Graphics, Inc. 29 */ 30 31 #include <GL/gl.h> 32 #include "glxclient.h" 33 34 /* 35 ** Return the number of elements per group of a specified format 36 */ 37 GLint 38 __glElementsPerGroup(GLenum format, GLenum type) 39 { 40 /* 41 ** To make row length computation valid for image extraction, 42 ** packed pixel types assume elements per group equals one. 43 */ 44 switch (type) { 45 case GL_UNSIGNED_BYTE_3_3_2: 46 case GL_UNSIGNED_BYTE_2_3_3_REV: 47 case GL_UNSIGNED_SHORT_5_6_5: 48 case GL_UNSIGNED_SHORT_5_6_5_REV: 49 case GL_UNSIGNED_SHORT_4_4_4_4: 50 case GL_UNSIGNED_SHORT_4_4_4_4_REV: 51 case GL_UNSIGNED_SHORT_5_5_5_1: 52 case GL_UNSIGNED_SHORT_1_5_5_5_REV: 53 case GL_UNSIGNED_SHORT_8_8_APPLE: 54 case GL_UNSIGNED_SHORT_8_8_REV_APPLE: 55 case GL_UNSIGNED_INT_8_8_8_8: 56 case GL_UNSIGNED_INT_8_8_8_8_REV: 57 case GL_UNSIGNED_INT_10_10_10_2: 58 case GL_UNSIGNED_INT_2_10_10_10_REV: 59 case GL_UNSIGNED_INT_24_8_NV: 60 return 1; 61 default: 62 break; 63 } 64 65 switch (format) { 66 case GL_RGB: 67 case GL_BGR: 68 return 3; 69 case GL_RG: 70 case GL_422_EXT: 71 case GL_422_REV_EXT: 72 case GL_422_AVERAGE_EXT: 73 case GL_422_REV_AVERAGE_EXT: 74 case GL_DEPTH_STENCIL_NV: 75 case GL_YCBCR_422_APPLE: 76 case GL_LUMINANCE_ALPHA: 77 return 2; 78 case GL_RGBA: 79 case GL_BGRA: 80 case GL_ABGR_EXT: 81 return 4; 82 case GL_COLOR_INDEX: 83 case GL_STENCIL_INDEX: 84 case GL_DEPTH_COMPONENT: 85 case GL_RED: 86 case GL_GREEN: 87 case GL_BLUE: 88 case GL_ALPHA: 89 case GL_LUMINANCE: 90 case GL_INTENSITY: 91 return 1; 92 default: 93 return 0; 94 } 95 } 96 97 /* 98 ** Return the number of bytes per element, based on the element type (other 99 ** than GL_BITMAP). 100 */ 101 GLint 102 __glBytesPerElement(GLenum type) 103 { 104 switch (type) { 105 case GL_UNSIGNED_SHORT: 106 case GL_SHORT: 107 case GL_UNSIGNED_SHORT_5_6_5: 108 case GL_UNSIGNED_SHORT_5_6_5_REV: 109 case GL_UNSIGNED_SHORT_4_4_4_4: 110 case GL_UNSIGNED_SHORT_4_4_4_4_REV: 111 case GL_UNSIGNED_SHORT_5_5_5_1: 112 case GL_UNSIGNED_SHORT_1_5_5_5_REV: 113 case GL_UNSIGNED_SHORT_8_8_APPLE: 114 case GL_UNSIGNED_SHORT_8_8_REV_APPLE: 115 return 2; 116 case GL_UNSIGNED_BYTE: 117 case GL_BYTE: 118 case GL_UNSIGNED_BYTE_3_3_2: 119 case GL_UNSIGNED_BYTE_2_3_3_REV: 120 return 1; 121 case GL_INT: 122 case GL_UNSIGNED_INT: 123 case GL_FLOAT: 124 case GL_UNSIGNED_INT_8_8_8_8: 125 case GL_UNSIGNED_INT_8_8_8_8_REV: 126 case GL_UNSIGNED_INT_10_10_10_2: 127 case GL_UNSIGNED_INT_2_10_10_10_REV: 128 case GL_UNSIGNED_INT_24_8_NV: 129 return 4; 130 default: 131 return 0; 132 } 133 } 134 135 /* 136 ** Compute memory required for internal packed array of data of given type 137 ** and format. 138 */ 139 GLint 140 __glImageSize(GLsizei width, GLsizei height, GLsizei depth, 141 GLenum format, GLenum type, GLenum target) 142 { 143 int bytes_per_row; 144 int components; 145 146 switch (target) { 147 case GL_PROXY_TEXTURE_1D: 148 case GL_PROXY_TEXTURE_2D: 149 case GL_PROXY_TEXTURE_3D: 150 case GL_PROXY_TEXTURE_4D_SGIS: 151 case GL_PROXY_TEXTURE_CUBE_MAP: 152 case GL_PROXY_TEXTURE_RECTANGLE_ARB: 153 case GL_PROXY_HISTOGRAM: 154 case GL_PROXY_COLOR_TABLE: 155 case GL_PROXY_TEXTURE_COLOR_TABLE_SGI: 156 case GL_PROXY_POST_CONVOLUTION_COLOR_TABLE: 157 case GL_PROXY_POST_COLOR_MATRIX_COLOR_TABLE: 158 case GL_PROXY_POST_IMAGE_TRANSFORM_COLOR_TABLE_HP: 159 return 0; 160 } 161 162 if (width < 0 || height < 0 || depth < 0) { 163 return 0; 164 } 165 166 /* 167 ** Zero is returned if either format or type are invalid. 168 */ 169 components = __glElementsPerGroup(format, type); 170 if (type == GL_BITMAP) { 171 if (format == GL_COLOR_INDEX || format == GL_STENCIL_INDEX) { 172 bytes_per_row = (width + 7) >> 3; 173 } 174 else { 175 return 0; 176 } 177 } 178 else { 179 bytes_per_row = __glBytesPerElement(type) * width; 180 } 181 182 return bytes_per_row * height * depth * components; 183 } 184