1 Name 2 3 MESA_packed_depth_stencil 4 5 Name Strings 6 7 GL_MESA_packed_depth_stencil 8 9 Contact 10 11 Keith Whitwell, VA Linux Systems Inc. (keithw 'at' valinux.com) 12 Brian Paul, VA Linux Systems Inc. (brianp 'at' valinux.com) 13 14 Status 15 16 Obsolete. 17 18 Version 19 20 21 Number 22 23 ??? 24 25 Dependencies 26 27 EXT_abgr affects the definition of this extension 28 SGIS_texture4D affects the definition of this extension 29 EXT_cmyka affects the definition of this extension 30 ARB_packed_pixels affects the definition of this extension 31 32 Overview 33 34 Provides a mechanism for DrawPixels and ReadPixels to efficiently 35 transfer depth and stencil image data. Specifically, we defined new 36 packed pixel formats and types which pack both stencil and depth 37 into one value. 38 39 Issues: 40 41 1. Is this the right way to distinguish between 24/8 and 8/24 42 pixel formats? Should we instead provide both: 43 44 GL_DEPTH_STENCIL_MESA 45 GL_STENCIL_DEPTH_MESA 46 47 And perhaps just use GL_UNSIGNED_INT, GL_UNSIGNED_SHORT ? 48 49 2. If not, is it correct to use _REV to indicate that stencil 50 preceeds depth in the 1_15 and 8_24 formats? 51 52 3. Do we really want the GL_UNSIGNED_SHORT formats? 53 54 55 New Procedures and Functions 56 57 None. 58 59 New Tokens 60 61 Accepted by the <format> parameter of ReadPixels and DrawPixels: 62 63 GL_DEPTH_STENCIL_MESA 0x8750 64 65 Accepted by the <type> parameter of ReadPixels and DrawPixels: 66 67 GL_UNSIGNED_INT_24_8_MESA 0x8751 68 GL_UNSIGNED_INT_8_24_REV_MESA 0x8752 69 GL_UNSIGNED_SHORT_15_1_MESA 0x8753 70 GL_UNSIGNED_SHORT_1_15_REV_MESA 0x8754 71 72 Additions to Chapter 2 of the 1.1 Specification (OpenGL Operation) 73 74 None 75 76 Additions to Chapter 3 of the 1.1 Specification (Rasterization) 77 78 One entry is added to table 3.5 (DrawPixels and ReadPixels formats). 79 The new table is: 80 81 Target 82 Format Name Buffer Element Meaning and Order 83 ----------- ------ ------------------------- 84 COLOR_INDEX Color Color index 85 STENCIL_INDEX Stencil Stencil index 86 DEPTH_COMPONENT Depth Depth component 87 RED Color R component 88 GREEN Color G component 89 BLUE Color B component 90 ALPHA Color A component 91 RGB Color R, G, B components 92 RGBA Color R, G, B, A components 93 BGRA Color B, G, R, A components 94 ABGR_EXT Color A, B, G, R components 95 CMYK_EXT Color Cyan, Magenta, Yellow, Black components 96 CMYKA_EXT Color Cyan, Magenta, Yellow, Black, A components 97 LUMINANCE Color Luminance component 98 LUMINANCE_ALPHA Color Luminance, A components 99 DEPTH_STENCIL Depth, Depth component, stencil index. 100 Stencil 101 102 Table 3.5: DrawPixels and ReadPixels formats. The third column 103 gives a description of and the number and order of elements in a 104 group. 105 106 Add to the description of packed pixel formats: 107 108 <type> Parameter Data of Matching 109 Token Name Type Elements Pixel Formats 110 ---------------- ---- -------- ------------- 111 112 UNSIGNED_BYTE_3_3_2 ubyte 3 RGB 113 UNSIGNED_BYTE_2_3_3_REV ubyte 3 RGB 114 UNSIGNED_SHORT_5_6_5 ushort 3 RGB 115 UNSIGNED_SHORT_5_6_5_REV ushort 3 RGB 116 UNSIGNED_SHORT_4_4_4_4 ushort 4 RGBA,BGRA,ABGR_EXT,CMYK_EXT 117 UNSIGNED_SHORT_4_4_4_4_REV ushort 4 RGBA,BGRA 118 UNSIGNED_SHORT_5_5_5_1 ushort 4 RGBA,BGRA,ABGR_EXT,CMYK_EXT 119 UNSIGNED_SHORT_1_5_5_5_REV ushort 4 RGBA,BGRA 120 UNSIGNED_INT_8_8_8_8 uint 4 RGBA,BGRA,ABGR_EXT,CMYK_EXT 121 UNSIGNED_INT_8_8_8_8_REV uint 4 RGBA,BGRA 122 UNSIGNED_INT_10_10_10_2 uint 4 RGBA,BGRA,ABGR_EXT,CMYK_EXT 123 UNSIGNED_INT_2_10_10_10_REV uint 4 RGBA,BGRA 124 UNSIGNED_SHORT_15_1_MESA ushort 2 DEPTH_STENCIL_MESA 125 UNSIGNED_SHORT_1_15_REV_MESA ushort 2 DEPTH_STENCIL_MESA 126 UNSIGNED_SHORT_24_8_MESA ushort 2 DEPTH_STENCIL_MESA 127 UNSIGNED_SHORT_8_24_REV_MESA ushort 2 DEPTH_STENCIL_MESA 128 129 UNSIGNED_INT_8_24: 130 131 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 132 +-----------------------+-----------------------------------------------------------------------+ 133 | | | 134 +-----------------------+-----------------------------------------------------------------------+ 135 136 first second 137 element element 138 139 140 UNSIGNED_INT_24_8: 141 142 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 143 +----------------------------------------------------------------------+------------------------+ 144 | | | 145 +----------------------------------------------------------------------+------------------------+ 146 147 first second 148 element element 149 150 UNSIGNED_SHORT_15_1: 151 152 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 153 +-----------------------------------------------------------+---+ 154 | | | 155 +-----------------------------------------------------------+---+ 156 157 first second 158 element element 159 160 161 UNSIGNED_SHORT_1_15_REV: 162 163 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 164 +---+-----------------------------------------------------------+ 165 | | | 166 +---+-----------------------------------------------------------+ 167 168 second first 169 element element 170 171 The assignment of elements to fields in the packed pixel is as 172 described in the table below: 173 174 First Second Third Fourth 175 Format Element Element Element Element 176 ------ ------- ------- ------- ------- 177 RGB red green blue 178 RGBA red green blue alpha 179 BGRA blue green red alpha 180 ABGR_EXT alpha blue green red 181 CMYK_EXT cyan magenta yellow black 182 DEPTH_STENCIL_MESA depth stencil 183 184 Additions to Chapter 4 of the 1.1 Specification (Per-Fragment Operations 185 and the Frame Buffer) 186 187 The new format is added to the discussion of Obtaining Pixels from the 188 Framebuffer. It should read " If the <format> is one of RED, GREEN, 189 BLUE, ALPHA, RGB, RGBA, ABGR_EXT, LUMINANCE, or LUMINANCE_ALPHA, and 190 the GL is in color index mode, then the color index is obtained." 191 192 The new format is added to the discussion of Index Lookup. It should 193 read "If <format> is one of RED, GREEN, BLUE, ALPHA, RGB, RGBA, 194 ABGR_EXT, LUMINANCE, or LUMINANCE_ALPHA, then the index is used to 195 reference 4 tables of color components: PIXEL_MAP_I_TO_R, 196 PIXEL_MAP_I_TO_G, PIXEL_MAP_I_TO_B, and PIXEL_MAP_I_TO_A." 197 198 199 Additions to Chapter 5 of the 1.1 Specification (Special Functions) 200 201 None 202 203 Additions to Chapter 6 of the 1.1 Specification (State and State Requests) 204 205 None 206 207 Additions to the GLX Specification 208 209 None 210 211 GLX Protocol 212 213 TBD 214 215 Errors 216 217 None 218 219 New State 220 221 None 222 223 Revision History 224 225 Version 1.0 - 23 Sep 2000 226 Keith's original version. 227 228 Version 1.1 - 3 Nov 2000 229 Brian's edits, assigned values to new enums. 230 231
