1 /* 2 Copyright (C) Intel Corp. 2006. All Rights Reserved. 3 Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to 4 develop this 3D driver. 5 6 Permission is hereby granted, free of charge, to any person obtaining 7 a copy of this software and associated documentation files (the 8 "Software"), to deal in the Software without restriction, including 9 without limitation the rights to use, copy, modify, merge, publish, 10 distribute, sublicense, and/or sell copies of the Software, and to 11 permit persons to whom the Software is furnished to do so, subject to 12 the following conditions: 13 14 The above copyright notice and this permission notice (including the 15 next paragraph) shall be included in all copies or substantial 16 portions of the Software. 17 18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 19 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 20 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 21 IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE 22 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 23 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 24 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 25 26 **********************************************************************/ 27 /* 28 * Authors: 29 * Keith Whitwell <keith (at) tungstengraphics.com> 30 */ 31 32 #include "main/glheader.h" 33 #include "main/macros.h" 34 #include "main/enums.h" 35 #include "program/program.h" 36 37 #include "intel_batchbuffer.h" 38 39 #include "brw_defines.h" 40 #include "brw_context.h" 41 #include "brw_eu.h" 42 #include "brw_clip.h" 43 44 45 46 static void brw_clip_line_alloc_regs( struct brw_clip_compile *c ) 47 { 48 struct intel_context *intel = &c->func.brw->intel; 49 GLuint i = 0,j; 50 51 /* Register usage is static, precompute here: 52 */ 53 c->reg.R0 = retype(brw_vec8_grf(i, 0), BRW_REGISTER_TYPE_UD); i++; 54 55 if (c->key.nr_userclip) { 56 c->reg.fixed_planes = brw_vec4_grf(i, 0); 57 i += (6 + c->key.nr_userclip + 1) / 2; 58 59 c->prog_data.curb_read_length = (6 + c->key.nr_userclip + 1) / 2; 60 } 61 else 62 c->prog_data.curb_read_length = 0; 63 64 65 /* Payload vertices plus space for more generated vertices: 66 */ 67 for (j = 0; j < 4; j++) { 68 c->reg.vertex[j] = brw_vec4_grf(i, 0); 69 i += c->nr_regs; 70 } 71 72 c->reg.t = brw_vec1_grf(i, 0); 73 c->reg.t0 = brw_vec1_grf(i, 1); 74 c->reg.t1 = brw_vec1_grf(i, 2); 75 c->reg.planemask = retype(brw_vec1_grf(i, 3), BRW_REGISTER_TYPE_UD); 76 c->reg.plane_equation = brw_vec4_grf(i, 4); 77 i++; 78 79 c->reg.dp0 = brw_vec1_grf(i, 0); /* fixme - dp4 will clobber r.1,2,3 */ 80 c->reg.dp1 = brw_vec1_grf(i, 4); 81 i++; 82 83 if (!c->key.nr_userclip) { 84 c->reg.fixed_planes = brw_vec8_grf(i, 0); 85 i++; 86 } 87 88 if (intel->needs_ff_sync) { 89 c->reg.ff_sync = retype(brw_vec1_grf(i, 0), BRW_REGISTER_TYPE_UD); 90 i++; 91 } 92 93 c->first_tmp = i; 94 c->last_tmp = i; 95 96 c->prog_data.urb_read_length = c->nr_regs; /* ? */ 97 c->prog_data.total_grf = i; 98 } 99 100 101 102 /* Line clipping, more or less following the following algorithm: 103 * 104 * for (p=0;p<MAX_PLANES;p++) { 105 * if (clipmask & (1 << p)) { 106 * GLfloat dp0 = DOTPROD( vtx0, plane[p] ); 107 * GLfloat dp1 = DOTPROD( vtx1, plane[p] ); 108 * 109 * if (IS_NEGATIVE(dp1)) { 110 * GLfloat t = dp1 / (dp1 - dp0); 111 * if (t > t1) t1 = t; 112 * } else { 113 * GLfloat t = dp0 / (dp0 - dp1); 114 * if (t > t0) t0 = t; 115 * } 116 * 117 * if (t0 + t1 >= 1.0) 118 * return; 119 * } 120 * } 121 * 122 * interp( ctx, newvtx0, vtx0, vtx1, t0 ); 123 * interp( ctx, newvtx1, vtx1, vtx0, t1 ); 124 * 125 */ 126 static void clip_and_emit_line( struct brw_clip_compile *c ) 127 { 128 struct brw_compile *p = &c->func; 129 struct brw_context *brw = p->brw; 130 struct brw_indirect vtx0 = brw_indirect(0, 0); 131 struct brw_indirect vtx1 = brw_indirect(1, 0); 132 struct brw_indirect newvtx0 = brw_indirect(2, 0); 133 struct brw_indirect newvtx1 = brw_indirect(3, 0); 134 struct brw_indirect plane_ptr = brw_indirect(4, 0); 135 struct brw_reg v1_null_ud = retype(vec1(brw_null_reg()), BRW_REGISTER_TYPE_UD); 136 GLuint hpos_offset = brw_vert_result_to_offset(&c->vue_map, 137 VERT_RESULT_HPOS); 138 139 brw_MOV(p, get_addr_reg(vtx0), brw_address(c->reg.vertex[0])); 140 brw_MOV(p, get_addr_reg(vtx1), brw_address(c->reg.vertex[1])); 141 brw_MOV(p, get_addr_reg(newvtx0), brw_address(c->reg.vertex[2])); 142 brw_MOV(p, get_addr_reg(newvtx1), brw_address(c->reg.vertex[3])); 143 brw_MOV(p, get_addr_reg(plane_ptr), brw_clip_plane0_address(c)); 144 145 /* Note: init t0, t1 together: 146 */ 147 brw_MOV(p, vec2(c->reg.t0), brw_imm_f(0)); 148 149 brw_clip_init_planes(c); 150 brw_clip_init_clipmask(c); 151 152 /* -ve rhw workaround */ 153 if (brw->has_negative_rhw_bug) { 154 brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ); 155 brw_AND(p, brw_null_reg(), get_element_ud(c->reg.R0, 2), 156 brw_imm_ud(1<<20)); 157 brw_OR(p, c->reg.planemask, c->reg.planemask, brw_imm_ud(0x3f)); 158 } 159 160 brw_set_predicate_control(p, BRW_PREDICATE_NONE); 161 162 brw_DO(p, BRW_EXECUTE_1); 163 { 164 /* if (planemask & 1) 165 */ 166 brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ); 167 brw_AND(p, v1_null_ud, c->reg.planemask, brw_imm_ud(1)); 168 169 brw_IF(p, BRW_EXECUTE_1); 170 { 171 if (c->key.nr_userclip) 172 brw_MOV(p, c->reg.plane_equation, deref_4f(plane_ptr, 0)); 173 else 174 brw_MOV(p, c->reg.plane_equation, deref_4b(plane_ptr, 0)); 175 176 /* dp = DP4(vtx->position, plane) 177 */ 178 brw_DP4(p, vec4(c->reg.dp0), deref_4f(vtx0, hpos_offset), c->reg.plane_equation); 179 180 /* if (IS_NEGATIVE(dp1)) 181 */ 182 brw_set_conditionalmod(p, BRW_CONDITIONAL_L); 183 brw_DP4(p, vec4(c->reg.dp1), deref_4f(vtx1, hpos_offset), c->reg.plane_equation); 184 brw_IF(p, BRW_EXECUTE_1); 185 { 186 /* 187 * Both can be negative on GM965/G965 due to RHW workaround 188 * if so, this object should be rejected. 189 */ 190 if (brw->has_negative_rhw_bug) { 191 brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_LE, c->reg.dp0, brw_imm_f(0.0)); 192 brw_IF(p, BRW_EXECUTE_1); 193 { 194 brw_clip_kill_thread(c); 195 } 196 brw_ENDIF(p); 197 } 198 199 brw_ADD(p, c->reg.t, c->reg.dp1, negate(c->reg.dp0)); 200 brw_math_invert(p, c->reg.t, c->reg.t); 201 brw_MUL(p, c->reg.t, c->reg.t, c->reg.dp1); 202 203 brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_G, c->reg.t, c->reg.t1 ); 204 brw_MOV(p, c->reg.t1, c->reg.t); 205 brw_set_predicate_control(p, BRW_PREDICATE_NONE); 206 } 207 brw_ELSE(p); 208 { 209 /* Coming back in. We know that both cannot be negative 210 * because the line would have been culled in that case. 211 */ 212 213 /* If both are positive, do nothing */ 214 /* Only on GM965/G965 */ 215 if (brw->has_negative_rhw_bug) { 216 brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_L, c->reg.dp0, brw_imm_f(0.0)); 217 brw_IF(p, BRW_EXECUTE_1); 218 } 219 220 { 221 brw_ADD(p, c->reg.t, c->reg.dp0, negate(c->reg.dp1)); 222 brw_math_invert(p, c->reg.t, c->reg.t); 223 brw_MUL(p, c->reg.t, c->reg.t, c->reg.dp0); 224 225 brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_G, c->reg.t, c->reg.t0 ); 226 brw_MOV(p, c->reg.t0, c->reg.t); 227 brw_set_predicate_control(p, BRW_PREDICATE_NONE); 228 } 229 230 if (brw->has_negative_rhw_bug) { 231 brw_ENDIF(p); 232 } 233 } 234 brw_ENDIF(p); 235 } 236 brw_ENDIF(p); 237 238 /* plane_ptr++; 239 */ 240 brw_ADD(p, get_addr_reg(plane_ptr), get_addr_reg(plane_ptr), brw_clip_plane_stride(c)); 241 242 /* while (planemask>>=1) != 0 243 */ 244 brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ); 245 brw_SHR(p, c->reg.planemask, c->reg.planemask, brw_imm_ud(1)); 246 } 247 brw_WHILE(p); 248 249 brw_ADD(p, c->reg.t, c->reg.t0, c->reg.t1); 250 brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_L, c->reg.t, brw_imm_f(1.0)); 251 brw_IF(p, BRW_EXECUTE_1); 252 { 253 brw_clip_interp_vertex(c, newvtx0, vtx0, vtx1, c->reg.t0, false); 254 brw_clip_interp_vertex(c, newvtx1, vtx1, vtx0, c->reg.t1, false); 255 256 brw_clip_emit_vue(c, newvtx0, 1, 0, 257 (_3DPRIM_LINESTRIP << URB_WRITE_PRIM_TYPE_SHIFT) 258 | URB_WRITE_PRIM_START); 259 brw_clip_emit_vue(c, newvtx1, 0, 1, 260 (_3DPRIM_LINESTRIP << URB_WRITE_PRIM_TYPE_SHIFT) 261 | URB_WRITE_PRIM_END); 262 } 263 brw_ENDIF(p); 264 brw_clip_kill_thread(c); 265 } 266 267 268 269 void brw_emit_line_clip( struct brw_clip_compile *c ) 270 { 271 brw_clip_line_alloc_regs(c); 272 brw_clip_init_ff_sync(c); 273 274 if (c->key.do_flat_shading) { 275 if (c->key.pv_first) 276 brw_clip_copy_colors(c, 1, 0); 277 else 278 brw_clip_copy_colors(c, 0, 1); 279 } 280 281 clip_and_emit_line(c); 282 } 283
