src/mesa/drivers/dri/i965/brw_clip_util.c

   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@tungstengraphics.com>
  30   */
  31
  32
  33 #include "main/glheader.h"
  34 #include "main/macros.h"
  35 #include "main/enums.h"
  36 #include "shader/program.h"
  37
  38 #include "intel_batchbuffer.h"
  39
  40 #include "brw_defines.h"
  41 #include "brw_context.h"
  42 #include "brw_eu.h"
  43 #include "brw_util.h"
  44 #include "brw_clip.h"
  45
  46
  47
  48
  49 struct brw_reg get_tmp( struct brw_clip_compile *c )
  50 {
  51    struct brw_reg tmp = brw_vec4_grf(c->last_tmp, 0);
  52
  53    if (++c->last_tmp > c->prog_data.total_grf)
  54       c->prog_data.total_grf = c->last_tmp;
  55
  56    return tmp;
  57 }
  58
  59 static void release_tmp( struct brw_clip_compile *c, struct brw_reg tmp )
  60 {
  61    if (tmp.nr == c->last_tmp-1)
  62       c->last_tmp--;
  63 }
  64
  65
  66 static struct brw_reg make_plane_ud(GLuint x, GLuint y, GLuint z, GLuint w)
  67 {
  68    return brw_imm_ud((w<<24) | (z<<16) | (y<<8) | x);
  69 }
  70
  71
  72 void brw_clip_init_planes( struct brw_clip_compile *c )
  73 {
  74    struct brw_compile *p = &c->func;
  75
  76    if (!c->key.nr_userclip) {
  77       brw_MOV(p, get_element_ud(c->reg.fixed_planes, 0), make_plane_ud( 0,    0, 0xff, 1));
  78       brw_MOV(p, get_element_ud(c->reg.fixed_planes, 1), make_plane_ud( 0,    0,    1, 1));
  79       brw_MOV(p, get_element_ud(c->reg.fixed_planes, 2), make_plane_ud( 0, 0xff,    0, 1));
  80       brw_MOV(p, get_element_ud(c->reg.fixed_planes, 3), make_plane_ud( 0,    1,    0, 1));
  81       brw_MOV(p, get_element_ud(c->reg.fixed_planes, 4), make_plane_ud(0xff,  0,    0, 1));
  82       brw_MOV(p, get_element_ud(c->reg.fixed_planes, 5), make_plane_ud( 1,    0,    0, 1));
  83    }
  84 }
  85
  86
  87
  88 #define W 3
  89
  90 /* Project 'pos' to screen space (or back again), overwrite with results:
  91  */
  92 void brw_clip_project_position(struct brw_clip_compile *c, struct brw_reg pos )
  93 {
  94    struct brw_compile *p = &c->func;
  95
  96    /* calc rhw
  97     */
  98    brw_math_invert(p, get_element(pos, W), get_element(pos, W));
  99
 100    /* value.xyz *= value.rhw
 101     */
 102    brw_set_access_mode(p, BRW_ALIGN_16);
 103    brw_MUL(p, brw_writemask(pos, WRITEMASK_XYZ), pos, brw_swizzle1(pos, W));
 104    brw_set_access_mode(p, BRW_ALIGN_1);
 105 }
 106
 107
 108 static void brw_clip_project_vertex( struct brw_clip_compile *c,
 109                                      struct brw_indirect vert_addr )
 110 {
 111    struct brw_compile *p = &c->func;
 112    struct brw_reg tmp = get_tmp(c);
 113
 114    /* Fixup position.  Extract from the original vertex and re-project
 115     * to screen space:
 116     */
 117    brw_MOV(p, tmp, deref_4f(vert_addr, c->offset[VERT_RESULT_HPOS]));
 118    brw_clip_project_position(c, tmp);
 119    brw_MOV(p, deref_4f(vert_addr, c->header_position_offset), tmp);
 120
 121    release_tmp(c, tmp);
 122 }
 123
 124
 125
 126
 127 /* Interpolate between two vertices and put the result into a0.0.
 128  * Increment a0.0 accordingly.
 129  */
 130 void brw_clip_interp_vertex( struct brw_clip_compile *c,
 131                              struct brw_indirect dest_ptr,
 132                              struct brw_indirect v0_ptr, /* from */
 133                              struct brw_indirect v1_ptr, /* to */
 134                              struct brw_reg t0,
 135                              GLboolean force_edgeflag)
 136 {
 137    struct brw_compile *p = &c->func;
 138    struct brw_reg tmp = get_tmp(c);
 139    GLuint i;
 140
 141    /* Just copy the vertex header:
 142     */
 143    brw_copy_indirect_to_indirect(p, dest_ptr, v0_ptr, 1);
 144
 145    /* Iterate over each attribute (could be done in pairs?)
 146     */
 147    for (i = 0; i < c->nr_attrs; i++) {
 148       GLuint delta = i*16 + 32;
 149
 150       if (delta == c->offset[VERT_RESULT_EDGE]) {
 151          if (force_edgeflag)
 152             brw_MOV(p, deref_4f(dest_ptr, delta), brw_imm_f(1));
 153          else
 154             brw_MOV(p, deref_4f(dest_ptr, delta), deref_4f(v0_ptr, delta));
 155       }
 156       else {
 157          /* Interpolate:
 158           *
 159           *        New = attr0 + t*attr1 - t*attr0
 160           */
 161          brw_MUL(p,
 162                  vec4(brw_null_reg()),
 163                  deref_4f(v1_ptr, delta),
 164                  t0);
 165
 166          brw_MAC(p,
 167                  tmp,
 168                  negate(deref_4f(v0_ptr, delta)),
 169                  t0);
 170
 171          brw_ADD(p,
 172                  deref_4f(dest_ptr, delta),
 173                  deref_4f(v0_ptr, delta),
 174                  tmp);
 175       }
 176    }
 177
 178    if (i & 1) {
 179       GLuint delta = i*16 + 32;
 180       brw_MOV(p, deref_4f(dest_ptr, delta), brw_imm_f(0));
 181    }
 182
 183    release_tmp(c, tmp);
 184
 185    /* Recreate the projected (NDC) coordinate in the new vertex
 186     * header:
 187     */
 188    brw_clip_project_vertex(c, dest_ptr );
 189 }
 190
 191
 192
 193
 194 #define MAX_MRF 16
 195
 196 void brw_clip_emit_vue(struct brw_clip_compile *c,
 197                        struct brw_indirect vert,
 198                        GLboolean allocate,
 199                        GLboolean eot,
 200                        GLuint header)
 201 {
 202    struct brw_compile *p = &c->func;
 203    GLuint start = c->last_mrf;
 204
 205    assert(!(allocate && eot));
 206
 207    /* Cycle through mrf regs - probably futile as we have to wait for
 208     * the allocation response anyway.  Also, the order this function
 209     * is invoked doesn't correspond to the order the instructions will
 210     * be executed, so it won't have any effect in many cases.
 211     */
 212 #if 0
 213    if (start + c->nr_regs + 1 >= MAX_MRF)
 214       start = 0;
 215
 216    c->last_mrf = start + c->nr_regs + 1;
 217 #endif
 218
 219    /* Copy the vertex from vertn into m1..mN+1:
 220     */
 221    brw_copy_from_indirect(p, brw_message_reg(start+1), vert, c->nr_regs);
 222
 223    /* Overwrite PrimType and PrimStart in the message header, for
 224     * each vertex in turn:
 225     */
 226    brw_MOV(p, get_element_ud(c->reg.R0, 2), brw_imm_ud(header));
 227
 228
 229    /* Send each vertex as a seperate write to the urb.  This
 230     * is different to the concept in brw_sf_emit.c, where
 231     * subsequent writes are used to build up a single urb
 232     * entry.  Each of these writes instantiates a seperate
 233     * urb entry - (I think... what about 'allocate'?)
 234     */
 235    brw_urb_WRITE(p,
 236                  allocate ? c->reg.R0 : retype(brw_null_reg(), BRW_REGISTER_TYPE_UD),
 237                  start,
 238                  c->reg.R0,
 239                  allocate,
 240                  1,             /* used */
 241                  c->nr_regs + 1, /* msg length */
 242                  allocate ? 1 : 0, /* response_length */
 243                  eot,           /* eot */
 244                  1,             /* writes_complete */
 245                  0,             /* urb offset */
 246                  BRW_URB_SWIZZLE_NONE);
 247 }
 248
 249
 250
 251 void brw_clip_kill_thread(struct brw_clip_compile *c)
 252 {
 253    struct brw_compile *p = &c->func;
 254
 255    /* Send an empty message to kill the thread and release any
 256     * allocated urb entry:
 257     */
 258    brw_urb_WRITE(p,
 259                  retype(brw_null_reg(), BRW_REGISTER_TYPE_UD),
 260                  0,
 261                  c->reg.R0,
 262                  0,             /* allocate */
 263                  0,             /* used */
 264                  1,             /* msg len */
 265                  0,             /* response len */
 266                  1,             /* eot */
 267                  1,             /* writes complete */
 268                  0,
 269                  BRW_URB_SWIZZLE_NONE);
 270 }
 271
 272
 273
 274
 275 struct brw_reg brw_clip_plane0_address( struct brw_clip_compile *c )
 276 {
 277    return brw_address(c->reg.fixed_planes);
 278 }
 279
 280
 281 struct brw_reg brw_clip_plane_stride( struct brw_clip_compile *c )
 282 {
 283    if (c->key.nr_userclip) {
 284       return brw_imm_uw(16);
 285    }
 286    else {
 287       return brw_imm_uw(4);
 288    }
 289 }
 290
 291
 292 /* If flatshading, distribute color from provoking vertex prior to
 293  * clipping.
 294  */
 295 void brw_clip_copy_colors( struct brw_clip_compile *c,
 296                            GLuint to, GLuint from )
 297 {
 298    struct brw_compile *p = &c->func;
 299
 300    if (c->offset[VERT_RESULT_COL0])
 301       brw_MOV(p,
 302               byte_offset(c->reg.vertex[to], c->offset[VERT_RESULT_COL0]),
 303               byte_offset(c->reg.vertex[from], c->offset[VERT_RESULT_COL0]));
 304
 305    if (c->offset[VERT_RESULT_COL1])
 306       brw_MOV(p,
 307               byte_offset(c->reg.vertex[to], c->offset[VERT_RESULT_COL1]),
 308               byte_offset(c->reg.vertex[from], c->offset[VERT_RESULT_COL1]));
 309
 310    if (c->offset[VERT_RESULT_BFC0])
 311       brw_MOV(p,
 312               byte_offset(c->reg.vertex[to], c->offset[VERT_RESULT_BFC0]),
 313               byte_offset(c->reg.vertex[from], c->offset[VERT_RESULT_BFC0]));
 314
 315    if (c->offset[VERT_RESULT_BFC1])
 316       brw_MOV(p,
 317               byte_offset(c->reg.vertex[to], c->offset[VERT_RESULT_BFC1]),
 318               byte_offset(c->reg.vertex[from], c->offset[VERT_RESULT_BFC1]));
 319 }
 320
 321
 322
 323 void brw_clip_init_clipmask( struct brw_clip_compile *c )
 324 {
 325    struct brw_compile *p = &c->func;
 326    struct brw_reg incoming = get_element_ud(c->reg.R0, 2);
 327
 328    /* Shift so that lowest outcode bit is rightmost:
 329     */
 330    brw_SHR(p, c->reg.planemask, incoming, brw_imm_ud(26));
 331
 332    if (c->key.nr_userclip) {
 333       struct brw_reg tmp = retype(vec1(get_tmp(c)), BRW_REGISTER_TYPE_UD);
 334
 335       /* Rearrange userclip outcodes so that they come directly after
 336        * the fixed plane bits.
 337        */
 338       brw_AND(p, tmp, incoming, brw_imm_ud(0x3f<<14));
 339       brw_SHR(p, tmp, tmp, brw_imm_ud(8));
 340       brw_OR(p, c->reg.planemask, c->reg.planemask, tmp);
 341
 342       release_tmp(c, tmp);
 343    }
 344 }
 345