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 "main/glheader.h"
  33 #include "main/macros.h"
  34 #include "main/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 #define FRONT_UNFILLED_BIT  0x1
  46 #define BACK_UNFILLED_BIT   0x2
  47
  48
  49 static void compile_clip_prog( struct brw_context *brw,
  50                              struct brw_clip_prog_key *key )
  51 {
  52    struct intel_context *intel = &brw->intel;
  53    struct brw_clip_compile c;
  54    const GLuint *program;
  55    GLuint program_size;
  56    GLuint delta;
  57    GLuint i;
  58    GLuint header_regs;
  59
  60    memset(&c, 0, sizeof(c));
  61
  62    /* Begin the compilation:
  63     */
  64    brw_init_compile(brw, &c.func);
  65
  66    c.func.single_program_flow = 1;
  67
  68    c.key = *key;
  69
  70    /* Need to locate the two positions present in vertex + header.
  71     * These are currently hardcoded:
  72     */
  73    c.header_position_offset = ATTR_SIZE;
  74
  75    if (intel->gen == 5)
  76       header_regs = 3;
  77    else
  78       header_regs = 1;
  79
  80    delta = header_regs * REG_SIZE;
  81
  82    for (i = 0; i < VERT_RESULT_MAX; i++) {
  83       if (c.key.attrs & BITFIELD64_BIT(i)) {
  84          c.offset[i] = delta;
  85          delta += ATTR_SIZE;
  86
  87          c.idx_to_attr[c.nr_attrs] = i;
  88          c.nr_attrs++;
  89       }
  90    }
  91
  92    /* The vertex attributes start at a URB row-aligned offset after
  93     * the 8-20 dword vertex header, and continue for a URB row-aligned
  94     * length.  nr_regs determines the urb_read_length from the start
  95     * of the header to the end of the vertex data.
  96     */
  97    c.nr_regs = header_regs + (c.nr_attrs + 1) / 2;
  98
  99    c.nr_bytes = c.nr_regs * REG_SIZE;
 100
 101    c.prog_data.clip_mode = c.key.clip_mode; /* XXX */
 102
 103    /* For some reason the thread is spawned with only 4 channels
 104     * unmasked.
 105     */
 106    brw_set_mask_control(&c.func, BRW_MASK_DISABLE);
 107
 108
 109    /* Would ideally have the option of producing a program which could
 110     * do all three:
 111     */
 112    switch (key->primitive) {
 113    case GL_TRIANGLES:
 114       if (key->do_unfilled)
 115          brw_emit_unfilled_clip( &c );
 116       else
 117          brw_emit_tri_clip( &c );
 118       break;
 119    case GL_LINES:
 120       brw_emit_line_clip( &c );
 121       break;
 122    case GL_POINTS:
 123       brw_emit_point_clip( &c );
 124       break;
 125    default:
 126       assert(0);
 127       return;
 128    }
 129
 130
 131
 132    /* get the program
 133     */
 134    program = brw_get_program(&c.func, &program_size);
 135
 136    if (unlikely(INTEL_DEBUG & DEBUG_CLIP)) {
 137       printf("clip:\n");
 138       for (i = 0; i < program_size / sizeof(struct brw_instruction); i++)
 139          brw_disasm(stdout, &((struct brw_instruction *)program)[i],
 140                     intel->gen);
 141       printf("\n");
 142    }
 143
 144    /* Upload
 145     */
 146    drm_intel_bo_unreference(brw->clip.prog_bo);
 147    brw->clip.prog_bo = brw_upload_cache(&brw->cache,
 148                                         BRW_CLIP_PROG,
 149                                         &c.key, sizeof(c.key),
 150                                         program, program_size,
 151                                         &c.prog_data, sizeof(c.prog_data),
 152                                         &brw->clip.prog_data);
 153 }
 154
 155 /* Calculate interpolants for triangle and line rasterization.
 156  */
 157 static void upload_clip_prog(struct brw_context *brw)
 158 {
 159    struct intel_context *intel = &brw->intel;
 160    struct gl_context *ctx = &intel->ctx;
 161    struct brw_clip_prog_key key;
 162
 163    memset(&key, 0, sizeof(key));
 164
 165    /* Populate the key:
 166     */
 167    /* BRW_NEW_REDUCED_PRIMITIVE */
 168    key.primitive = brw->intel.reduced_primitive;
 169    /* CACHE_NEW_VS_PROG */
 170    key.attrs = brw->vs.prog_data->outputs_written;
 171    /* _NEW_LIGHT */
 172    key.do_flat_shading = (ctx->Light.ShadeModel == GL_FLAT);
 173    key.pv_first = (ctx->Light.ProvokingVertex == GL_FIRST_VERTEX_CONVENTION);
 174    /* _NEW_TRANSFORM */
 175    key.nr_userclip = brw_count_bits(ctx->Transform.ClipPlanesEnabled);
 176
 177    if (intel->gen == 5)
 178        key.clip_mode = BRW_CLIPMODE_KERNEL_CLIP;
 179    else
 180        key.clip_mode = BRW_CLIPMODE_NORMAL;
 181
 182    /* _NEW_POLYGON */
 183    if (key.primitive == GL_TRIANGLES) {
 184       if (ctx->Polygon.CullFlag &&
 185           ctx->Polygon.CullFaceMode == GL_FRONT_AND_BACK)
 186          key.clip_mode = BRW_CLIPMODE_REJECT_ALL;
 187       else {
 188          GLuint fill_front = CLIP_CULL;
 189          GLuint fill_back = CLIP_CULL;
 190          GLuint offset_front = 0;
 191          GLuint offset_back = 0;
 192
 193          if (!ctx->Polygon.CullFlag ||
 194              ctx->Polygon.CullFaceMode != GL_FRONT) {
 195             switch (ctx->Polygon.FrontMode) {
 196             case GL_FILL:
 197                fill_front = CLIP_FILL;
 198                offset_front = 0;
 199                break;
 200             case GL_LINE:
 201                fill_front = CLIP_LINE;
 202                offset_front = ctx->Polygon.OffsetLine;
 203                break;
 204             case GL_POINT:
 205                fill_front = CLIP_POINT;
 206                offset_front = ctx->Polygon.OffsetPoint;
 207                break;
 208             }
 209          }
 210
 211          if (!ctx->Polygon.CullFlag ||
 212              ctx->Polygon.CullFaceMode != GL_BACK) {
 213             switch (ctx->Polygon.BackMode) {
 214             case GL_FILL:
 215                fill_back = CLIP_FILL;
 216                offset_back = 0;
 217                break;
 218             case GL_LINE:
 219                fill_back = CLIP_LINE;
 220                offset_back = ctx->Polygon.OffsetLine;
 221                break;
 222             case GL_POINT:
 223                fill_back = CLIP_POINT;
 224                offset_back = ctx->Polygon.OffsetPoint;
 225                break;
 226             }
 227          }
 228
 229          if (ctx->Polygon.BackMode != GL_FILL ||
 230              ctx->Polygon.FrontMode != GL_FILL) {
 231             key.do_unfilled = 1;
 232
 233             /* Most cases the fixed function units will handle.  Cases where
 234              * one or more polygon faces are unfilled will require help:
 235              */
 236             key.clip_mode = BRW_CLIPMODE_CLIP_NON_REJECTED;
 237
 238             if (offset_back || offset_front) {
 239                /* _NEW_POLYGON, _NEW_BUFFERS */
 240                key.offset_units = ctx->Polygon.OffsetUnits * brw->intel.polygon_offset_scale;
 241                key.offset_factor = ctx->Polygon.OffsetFactor * ctx->DrawBuffer->_MRD;
 242             }
 243
 244             switch (ctx->Polygon.FrontFace) {
 245             case GL_CCW:
 246                key.fill_ccw = fill_front;
 247                key.fill_cw = fill_back;
 248                key.offset_ccw = offset_front;
 249                key.offset_cw = offset_back;
 250                if (ctx->Light.Model.TwoSide &&
 251                    key.fill_cw != CLIP_CULL)
 252                   key.copy_bfc_cw = 1;
 253                break;
 254             case GL_CW:
 255                key.fill_cw = fill_front;
 256                key.fill_ccw = fill_back;
 257                key.offset_cw = offset_front;
 258                key.offset_ccw = offset_back;
 259                if (ctx->Light.Model.TwoSide &&
 260                    key.fill_ccw != CLIP_CULL)
 261                   key.copy_bfc_ccw = 1;
 262                break;
 263             }
 264          }
 265       }
 266    }
 267
 268    drm_intel_bo_unreference(brw->clip.prog_bo);
 269    brw->clip.prog_bo = brw_search_cache(&brw->cache, BRW_CLIP_PROG,
 270                                         &key, sizeof(key),
 271                                         &brw->clip.prog_data);
 272    if (brw->clip.prog_bo == NULL)
 273       compile_clip_prog( brw, &key );
 274 }
 275
 276
 277 const struct brw_tracked_state brw_clip_prog = {
 278    .dirty = {
 279       .mesa  = (_NEW_LIGHT |
 280                 _NEW_TRANSFORM |
 281                 _NEW_POLYGON |
 282                 _NEW_BUFFERS),
 283       .brw   = (BRW_NEW_REDUCED_PRIMITIVE),
 284       .cache = CACHE_NEW_VS_PROG
 285    },
 286    .prepare = upload_clip_prog
 287 };