1 /* 2 * Copyright 2012 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 #include "intel_batchbuffer.h" 25 26 #include "brw_context.h" 27 #include "brw_defines.h" 28 #include "brw_multisample_state.h" 29 #include "main/framebuffer.h" 30 31 void 32 gen6_get_sample_position(struct gl_context *ctx, 33 struct gl_framebuffer *fb, 34 GLuint index, GLfloat *result) 35 { 36 uint8_t bits; 37 38 switch (_mesa_geometric_samples(fb)) { 39 case 1: 40 result[0] = result[1] = 0.5f; 41 return; 42 case 2: 43 bits = brw_multisample_positions_1x_2x >> (8 * index); 44 break; 45 case 4: 46 bits = brw_multisample_positions_4x >> (8 * index); 47 break; 48 case 8: 49 bits = brw_multisample_positions_8x[index >> 2] >> (8 * (index & 3)); 50 break; 51 case 16: 52 bits = brw_multisample_positions_16x[index >> 2] >> (8 * (index & 3)); 53 break; 54 default: 55 unreachable("Not implemented"); 56 } 57 58 /* Convert from U0.4 back to a floating point coordinate. */ 59 result[0] = ((bits >> 4) & 0xf) / 16.0f; 60 result[1] = (bits & 0xf) / 16.0f; 61 } 62 63 /** 64 * Sample index layout shows the numbering of slots in a rectangular 65 * grid of samples with in a pixel. Sample number layout shows the 66 * rectangular grid of samples roughly corresponding to the real sample 67 * locations with in a pixel. Sample number layout matches the sample 68 * index layout in case of 2X and 4x MSAA, but they are different in 69 * case of 8X MSAA. 70 * 71 * 2X MSAA sample index / number layout 72 * --------- 73 * | 0 | 1 | 74 * --------- 75 * 76 * 4X MSAA sample index / number layout 77 * --------- 78 * | 0 | 1 | 79 * --------- 80 * | 2 | 3 | 81 * --------- 82 * 83 * 8X MSAA sample index layout 8x MSAA sample number layout 84 * --------- --------- 85 * | 0 | 1 | | 5 | 2 | 86 * --------- --------- 87 * | 2 | 3 | | 4 | 6 | 88 * --------- --------- 89 * | 4 | 5 | | 0 | 3 | 90 * --------- --------- 91 * | 6 | 7 | | 7 | 1 | 92 * --------- --------- 93 * 94 * 16X MSAA sample index layout 16x MSAA sample number layout 95 * ----------------- ----------------- 96 * | 0 | 1 | 2 | 3 | |15 |10 | 9 | 7 | 97 * ----------------- ----------------- 98 * | 4 | 5 | 6 | 7 | | 4 | 1 | 3 |13 | 99 * ----------------- ----------------- 100 * | 8 | 9 |10 |11 | |12 | 2 | 0 | 6 | 101 * ----------------- ----------------- 102 * |12 |13 |14 |15 | |11 | 8 | 5 |14 | 103 * ----------------- ----------------- 104 * 105 * A sample map is used to map sample indices to sample numbers. 106 */ 107 void 108 gen6_set_sample_maps(struct gl_context *ctx) 109 { 110 uint8_t map_2x[2] = {0, 1}; 111 uint8_t map_4x[4] = {0, 1, 2, 3}; 112 uint8_t map_8x[8] = {3, 7, 5, 0, 1, 2, 4, 6}; 113 uint8_t map_16x[16] = { 15, 10, 9, 7, 4, 1, 3, 13, 114 12, 2, 0, 6, 11, 8, 5, 14 }; 115 116 memcpy(ctx->Const.SampleMap2x, map_2x, sizeof(map_2x)); 117 memcpy(ctx->Const.SampleMap4x, map_4x, sizeof(map_4x)); 118 memcpy(ctx->Const.SampleMap8x, map_8x, sizeof(map_8x)); 119 memcpy(ctx->Const.SampleMap16x, map_16x, sizeof(map_16x)); 120 } 121 122 /** 123 * 3DSTATE_MULTISAMPLE 124 */ 125 void 126 gen6_emit_3dstate_multisample(struct brw_context *brw, 127 unsigned num_samples) 128 { 129 uint32_t number_of_multisamples = 0; 130 uint32_t sample_positions_3210 = 0; 131 uint32_t sample_positions_7654 = 0; 132 133 assert(brw->gen < 8); 134 135 switch (num_samples) { 136 case 0: 137 case 1: 138 number_of_multisamples = MS_NUMSAMPLES_1; 139 break; 140 case 4: 141 number_of_multisamples = MS_NUMSAMPLES_4; 142 sample_positions_3210 = brw_multisample_positions_4x; 143 break; 144 case 8: 145 number_of_multisamples = MS_NUMSAMPLES_8; 146 sample_positions_3210 = brw_multisample_positions_8x[0]; 147 sample_positions_7654 = brw_multisample_positions_8x[1]; 148 break; 149 default: 150 unreachable("Unrecognized num_samples in gen6_emit_3dstate_multisample"); 151 } 152 153 int len = brw->gen >= 7 ? 4 : 3; 154 BEGIN_BATCH(len); 155 OUT_BATCH(_3DSTATE_MULTISAMPLE << 16 | (len - 2)); 156 OUT_BATCH(MS_PIXEL_LOCATION_CENTER | number_of_multisamples); 157 OUT_BATCH(sample_positions_3210); 158 if (brw->gen >= 7) 159 OUT_BATCH(sample_positions_7654); 160 ADVANCE_BATCH(); 161 } 162 163 unsigned 164 gen6_determine_sample_mask(struct brw_context *brw) 165 { 166 struct gl_context *ctx = &brw->ctx; 167 float coverage = 1.0f; 168 float coverage_invert = false; 169 unsigned sample_mask = ~0u; 170 171 /* BRW_NEW_NUM_SAMPLES */ 172 unsigned num_samples = brw->num_samples; 173 174 if (_mesa_is_multisample_enabled(ctx)) { 175 if (ctx->Multisample.SampleCoverage) { 176 coverage = ctx->Multisample.SampleCoverageValue; 177 coverage_invert = ctx->Multisample.SampleCoverageInvert; 178 } 179 if (ctx->Multisample.SampleMask) { 180 sample_mask = ctx->Multisample.SampleMaskValue; 181 } 182 } 183 184 if (num_samples > 1) { 185 int coverage_int = (int) (num_samples * coverage + 0.5f); 186 uint32_t coverage_bits = (1 << coverage_int) - 1; 187 if (coverage_invert) 188 coverage_bits ^= (1 << num_samples) - 1; 189 return coverage_bits & sample_mask; 190 } else { 191 return 1; 192 } 193 } 194 195 /** 196 * 3DSTATE_SAMPLE_MASK 197 */ 198 void 199 gen6_emit_3dstate_sample_mask(struct brw_context *brw, unsigned mask) 200 { 201 BEGIN_BATCH(2); 202 OUT_BATCH(_3DSTATE_SAMPLE_MASK << 16 | (2 - 2)); 203 OUT_BATCH(mask); 204 ADVANCE_BATCH(); 205 } 206 207 static void 208 upload_multisample_state(struct brw_context *brw) 209 { 210 /* BRW_NEW_NUM_SAMPLES */ 211 gen6_emit_3dstate_multisample(brw, brw->num_samples); 212 gen6_emit_3dstate_sample_mask(brw, gen6_determine_sample_mask(brw)); 213 } 214 215 const struct brw_tracked_state gen6_multisample_state = { 216 .dirty = { 217 .mesa = _NEW_MULTISAMPLE, 218 .brw = BRW_NEW_BLORP | 219 BRW_NEW_CONTEXT | 220 BRW_NEW_NUM_SAMPLES, 221 }, 222 .emit = upload_multisample_state 223 }; 224