src/mesa/drivers/dri/i965/brw_clip.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 #include "glheader.h"
  33 #include "macros.h"
  34 #include "enums.h"
  35
  36 #include "intel_batchbuffer.h"
  37
  38 #include "brw_defines.h"
  39 #include "brw_context.h"
  40 #include "brw_eu.h"
  41 #include "brw_util.h"
  42 #include "brw_state.h"
  43 #include "brw_clip.h"
  44
  45
  46 #define FRONT_UNFILLED_BIT  0x1
  47 #define BACK_UNFILLED_BIT   0x2
  48
  49
  50 static void compile_clip_prog( struct brw_context *brw,
  51                              struct brw_clip_prog_key *key )
  52 {
  53    struct brw_clip_compile c;
  54    const GLuint *program;
  55    GLuint program_size;
  56    GLuint delta;
  57    GLuint i;
  58
  59    memset(&c, 0, sizeof(c));
  60
  61    /* Begin the compilation:
  62     */
  63    brw_init_compile(&c.func);
  64
  65    c.key = *key;
  66
  67
  68    /* Need to locate the two positions present in vertex + header.
  69     * These are currently hardcoded:
  70     */
  71    c.header_position_offset = ATTR_SIZE;
  72
  73    for (i = 0, delta = REG_SIZE; i < VERT_RESULT_MAX; i++)
  74       if (c.key.attrs & (1<<i)) {
  75          c.offset[i] = delta;
  76          delta += ATTR_SIZE;
  77       }
  78
  79    c.nr_attrs = brw_count_bits(c.key.attrs);
  80    c.nr_regs = (c.nr_attrs + 1) / 2 + 1;  /* are vertices packed, or reg-aligned? */
  81    c.nr_bytes = c.nr_regs * REG_SIZE;
  82
  83    c.prog_data.clip_mode = c.key.clip_mode; /* XXX */
  84
  85    /* For some reason the thread is spawned with only 4 channels
  86     * unmasked.
  87     */
  88    brw_set_mask_control(&c.func, BRW_MASK_DISABLE);
  89
  90
  91    /* Would ideally have the option of producing a program which could
  92     * do all three:
  93     */
  94    switch (key->primitive) {
  95    case GL_TRIANGLES:
  96       if (key->do_unfilled)
  97          brw_emit_unfilled_clip( &c );
  98       else
  99          brw_emit_tri_clip( &c );
 100       break;
 101    case GL_LINES:
 102       brw_emit_line_clip( &c );
 103       break;
 104    case GL_POINTS:
 105       brw_emit_point_clip( &c );
 106       break;
 107    default:
 108       assert(0);
 109       return;
 110    }
 111
 112
 113
 114    /* get the program
 115     */
 116    program = brw_get_program(&c.func, &program_size);
 117
 118    /* Upload
 119     */
 120    brw->clip.prog_gs_offset = brw_upload_cache( &brw->cache[BRW_CLIP_PROG],
 121                                                 &c.key,
 122                                                 sizeof(c.key),
 123                                                 program,
 124                                                 program_size,
 125                                                 &c.prog_data,
 126                                                 &brw->clip.prog_data );
 127 }
 128
 129
 130 static GLboolean search_cache( struct brw_context *brw,
 131                                struct brw_clip_prog_key *key )
 132 {
 133    return brw_search_cache(&brw->cache[BRW_CLIP_PROG],
 134                            key, sizeof(*key),
 135                            &brw->clip.prog_data,
 136                            &brw->clip.prog_gs_offset);
 137 }
 138
 139
 140
 141
 142 /* Calculate interpolants for triangle and line rasterization.
 143  */
 144 static void upload_clip_prog( struct brw_context *brw )
 145 {
 146    GLcontext *ctx = &brw->intel.ctx;
 147    struct brw_clip_prog_key key;
 148
 149    memset(&key, 0, sizeof(key));
 150
 151    /* Populate the key:
 152     */
 153    /* BRW_NEW_REDUCED_PRIMITIVE */
 154    key.primitive = brw->intel.reduced_primitive;
 155    /* CACHE_NEW_VS_PROG */
 156    key.attrs = brw->vs.prog_data->outputs_written;
 157    /* _NEW_LIGHT */
 158    key.do_flat_shading = (brw->attribs.Light->ShadeModel == GL_FLAT);
 159    /* _NEW_TRANSFORM */
 160    key.nr_userclip = brw_count_bits(brw->attribs.Transform->ClipPlanesEnabled);
 161    key.clip_mode = BRW_CLIPMODE_NORMAL;
 162
 163    /* _NEW_POLYGON */
 164    if (key.primitive == GL_TRIANGLES) {
 165       if (brw->attribs.Polygon->CullFaceMode == GL_FRONT_AND_BACK)
 166          key.clip_mode = BRW_CLIPMODE_REJECT_ALL;
 167       else {
 168          GLuint fill_front = CLIP_CULL;
 169          GLuint fill_back = CLIP_CULL;
 170          GLuint offset_front = 0;
 171          GLuint offset_back = 0;
 172
 173          if (!brw->attribs.Polygon->CullFlag ||
 174              brw->attribs.Polygon->CullFaceMode != GL_FRONT) {
 175             switch (brw->attribs.Polygon->FrontMode) {
 176             case GL_FILL:
 177                fill_front = CLIP_FILL;
 178                offset_front = 0;
 179                break;
 180             case GL_LINE:
 181                key.do_unfilled = 1;
 182                fill_front = CLIP_LINE;
 183                offset_front = brw->attribs.Polygon->OffsetLine;
 184                break;
 185             case GL_POINT:
 186                key.do_unfilled = 1;
 187                fill_front = CLIP_POINT;
 188                offset_front = brw->attribs.Polygon->OffsetPoint;
 189                break;
 190             }
 191          }
 192
 193          if (!brw->attribs.Polygon->CullFlag ||
 194              brw->attribs.Polygon->CullFaceMode != GL_BACK) {
 195             switch (brw->attribs.Polygon->BackMode) {
 196             case GL_FILL:
 197                fill_back = CLIP_FILL;
 198                offset_back = 0;
 199                break;
 200             case GL_LINE:
 201                key.do_unfilled = 1;
 202                fill_back = CLIP_LINE;
 203                offset_back = brw->attribs.Polygon->OffsetLine;
 204                break;
 205             case GL_POINT:
 206                key.do_unfilled = 1;
 207                fill_back = CLIP_POINT;
 208                offset_back = brw->attribs.Polygon->OffsetPoint;
 209                break;
 210             }
 211          }
 212
 213          /* Most cases the fixed function units will handle.  Cases where
 214           * one or more polygon faces are unfilled will require help:
 215           */
 216          if (key.do_unfilled) {
 217             key.clip_mode = BRW_CLIPMODE_CLIP_NON_REJECTED;
 218
 219             if (offset_back || offset_front) {
 220                /* _NEW_POLYGON, _NEW_BUFFERS */
 221                key.offset_units = brw->attribs.Polygon->OffsetUnits * brw->intel.polygon_offset_scale;
 222                key.offset_factor = brw->attribs.Polygon->OffsetFactor * ctx->DrawBuffer->_MRD;
 223             }
 224
 225             switch (brw->attribs.Polygon->FrontFace) {
 226             case GL_CCW:
 227                key.fill_ccw = fill_front;
 228                key.fill_cw = fill_back;
 229                key.offset_ccw = offset_front;
 230                key.offset_cw = offset_back;
 231                if (brw->attribs.Light->Model.TwoSide &&
 232                    key.fill_cw != CLIP_CULL)
 233                   key.copy_bfc_cw = 1;
 234                break;
 235             case GL_CW:
 236                key.fill_cw = fill_front;
 237                key.fill_ccw = fill_back;
 238                key.offset_cw = offset_front;
 239                key.offset_ccw = offset_back;
 240                if (brw->attribs.Light->Model.TwoSide &&
 241                    key.fill_ccw != CLIP_CULL)
 242                   key.copy_bfc_ccw = 1;
 243                break;
 244             }
 245          }
 246       }
 247    }
 248
 249    if (!search_cache(brw, &key))
 250       compile_clip_prog( brw, &key );
 251 }
 252
 253
 254 const struct brw_tracked_state brw_clip_prog = {
 255    .dirty = {
 256       .mesa  = (_NEW_LIGHT |
 257                 _NEW_TRANSFORM |
 258                 _NEW_POLYGON |
 259                 _NEW_BUFFERS),
 260       .brw   = (BRW_NEW_REDUCED_PRIMITIVE),
 261       .cache = CACHE_NEW_VS_PROG
 262    },
 263    .update = upload_clip_prog
 264 };