1 /* 2 * Copyright 2013 Intel Corporation 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 21 * IN THE SOFTWARE. 22 */ 23 24 #ifndef BRW_MULTISAMPLE_STATE_H 25 #define BRW_MULTISAMPLE_STATE_H 26 27 #include <stdint.h> 28 29 /** 30 * Note: There are no standard multisample positions defined in OpenGL 31 * specifications. Implementations have the freedom to pick the positions 32 * which give plausible results. But the Vulkan specification does define 33 * standard sample positions. So, we decided to pick the same pattern in 34 * OpenGL as in Vulkan to keep it uniform across drivers and also to avoid 35 * breaking applications which rely on this standard pattern. 36 */ 37 38 /** 39 * 1x MSAA has a single sample at the center: (0.5, 0.5) -> (0x8, 0x8). 40 * 41 * 2x MSAA sample positions are (0.25, 0.25) and (0.75, 0.75): 42 * 4 c 43 * 4 0 44 * c 1 45 */ 46 static const uint32_t 47 brw_multisample_positions_1x_2x = 0x0088cc44; 48 49 /** 50 * Sample positions: 51 * 2 6 a e 52 * 2 0 53 * 6 1 54 * a 2 55 * e 3 56 */ 57 static const uint32_t 58 brw_multisample_positions_4x = 0xae2ae662; 59 60 /** 61 * Sample positions: 62 * 63 * From the Ivy Bridge PRM, Vol2 Part1 p304 (3DSTATE_MULTISAMPLE: 64 * Programming Notes): 65 * "When programming the sample offsets (for NUMSAMPLES_4 or _8 and 66 * MSRASTMODE_xxx_PATTERN), the order of the samples 0 to 3 (or 7 67 * for 8X) must have monotonically increasing distance from the 68 * pixel center. This is required to get the correct centroid 69 * computation in the device." 70 * 71 * Sample positions: 72 * 1 3 5 7 9 b d f 73 * 1 7 74 * 3 3 75 * 5 0 76 * 7 5 77 * 9 2 78 * b 1 79 * d 4 80 * f 6 81 */ 82 static const uint32_t 83 brw_multisample_positions_8x[] = { 0x53d97b95, 0xf1bf173d }; 84 85 /** 86 * Sample positions: 87 * 88 * 0 1 2 3 4 5 6 7 8 9 a b c d e f 89 * 0 15 90 * 1 9 91 * 2 10 92 * 3 7 93 * 4 13 94 * 5 1 95 * 6 4 96 * 7 3 97 * 8 12 98 * 9 0 99 * a 2 100 * b 6 101 * c 11 102 * d 5 103 * e 8 104 * f 14 105 */ 106 static const uint32_t 107 brw_multisample_positions_16x[] = { 108 0xc75a7599, 0xb3dbad36, 0x2c42816e, 0x10eff408 109 }; 110 111 #endif /* BRW_MULTISAMPLE_STATE_H */ 112
