src/gallium/drivers/i965simple/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 "brw_defines.h"
  33 #include "brw_context.h"
  34 #include "brw_eu.h"
  35 #include "brw_util.h"
  36 #include "brw_state.h"
  37 #include "brw_clip.h"
  38
  39 #define FRONT_UNFILLED_BIT  0x1
  40 #define BACK_UNFILLED_BIT   0x2
  41
  42
  43 static void compile_clip_prog( struct brw_context *brw,
  44                              struct brw_clip_prog_key *key )
  45 {
  46    struct brw_clip_compile c;
  47    const unsigned *program;
  48    unsigned program_size;
  49    unsigned delta;
  50    unsigned i;
  51
  52    memset(&c, 0, sizeof(c));
  53
  54    /* Begin the compilation:
  55     */
  56    brw_init_compile(&c.func);
  57
  58    c.func.single_program_flow = 1;
  59
  60    c.key = *key;
  61
  62
  63    /* Need to locate the two positions present in vertex + header.
  64     * These are currently hardcoded:
  65     */
  66    c.header_position_offset = ATTR_SIZE;
  67
  68    for (i = 0, delta = REG_SIZE; i < PIPE_MAX_SHADER_OUTPUTS; i++)
  69       if (c.key.attrs & (1<<i)) {
  70          c.offset[i] = delta;
  71          delta += ATTR_SIZE;
  72       }
  73
  74    c.nr_attrs = brw_count_bits(c.key.attrs);
  75    c.nr_regs = (c.nr_attrs + 1) / 2 + 1;  /* are vertices packed, or reg-aligned? */
  76    c.nr_bytes = c.nr_regs * REG_SIZE;
  77
  78    c.prog_data.clip_mode = c.key.clip_mode; /* XXX */
  79
  80    /* For some reason the thread is spawned with only 4 channels
  81     * unmasked.
  82     */
  83    brw_set_mask_control(&c.func, BRW_MASK_DISABLE);
  84
  85
  86    /* Would ideally have the option of producing a program which could
  87     * do all three:
  88     */
  89    switch (key->primitive) {
  90    case PIPE_PRIM_TRIANGLES:
  91 #if 0
  92       if (key->do_unfilled)
  93          brw_emit_unfilled_clip( &c );
  94       else
  95 #endif
  96          brw_emit_tri_clip( &c );
  97       break;
  98    case PIPE_PRIM_LINES:
  99       brw_emit_line_clip( &c );
 100       break;
 101    case PIPE_PRIM_POINTS:
 102       brw_emit_point_clip( &c );
 103       break;
 104    default:
 105       assert(0);
 106       return;
 107    }
 108
 109
 110
 111    /* get the program
 112     */
 113    program = brw_get_program(&c.func, &program_size);
 114
 115    /* Upload
 116     */
 117    brw->clip.prog_gs_offset = brw_upload_cache( &brw->cache[BRW_CLIP_PROG],
 118                                                 &c.key,
 119                                                 sizeof(c.key),
 120                                                 program,
 121                                                 program_size,
 122                                                 &c.prog_data,
 123                                                 &brw->clip.prog_data );
 124 }
 125
 126
 127 static boolean search_cache( struct brw_context *brw,
 128                                struct brw_clip_prog_key *key )
 129 {
 130    return brw_search_cache(&brw->cache[BRW_CLIP_PROG],
 131                            key, sizeof(*key),
 132                            &brw->clip.prog_data,
 133                            &brw->clip.prog_gs_offset);
 134 }
 135
 136
 137
 138
 139 /* Calculate interpolants for triangle and line rasterization.
 140  */
 141 static void upload_clip_prog(struct brw_context *brw)
 142 {
 143    struct brw_clip_prog_key key;
 144
 145    memset(&key, 0, sizeof(key));
 146
 147    /* Populate the key:
 148     */
 149    /* BRW_NEW_REDUCED_PRIMITIVE */
 150    key.primitive = brw->reduced_primitive;
 151    /* CACHE_NEW_VS_PROG */
 152    key.attrs = brw->vs.prog_data->outputs_written;
 153    /* BRW_NEW_RASTER */
 154    key.do_flat_shading = (brw->attribs.Raster->flatshade);
 155    /* BRW_NEW_CLIP */
 156    key.nr_userclip = brw->attribs.Clip.nr; /* XXX */
 157
 158 #if 0
 159    key.clip_mode = BRW_CLIPMODE_NORMAL;
 160
 161    if (key.primitive == PIPE_PRIM_TRIANGLES) {
 162       if (brw->attribs.Raster->cull_mode == PIPE_WINDING_BOTH)
 163          key.clip_mode = BRW_CLIPMODE_REJECT_ALL;
 164       else {
 165          if (brw->attribs.Raster->fill_cw != PIPE_POLYGON_MODE_FILL ||
 166              brw->attribs.Raster->fill_ccw != PIPE_POLYGON_MODE_FILL)
 167             key.do_unfilled = 1;
 168
 169          /* Most cases the fixed function units will handle.  Cases where
 170           * one or more polygon faces are unfilled will require help:
 171           */
 172          if (key.do_unfilled) {
 173             key.clip_mode = BRW_CLIPMODE_CLIP_NON_REJECTED;
 174
 175             if (brw->attribs.Raster->offset_cw ||
 176                 brw->attribs.Raster->offset_ccw) {
 177                key.offset_units = brw->attribs.Raster->offset_units;
 178                key.offset_factor = brw->attribs.Raster->offset_scale;
 179             }
 180             key.fill_ccw = brw->attribs.Raster->fill_ccw;
 181             key.fill_cw = brw->attribs.Raster->fill_cw;
 182             key.offset_ccw = brw->attribs.Raster->offset_ccw;
 183             key.offset_cw = brw->attribs.Raster->offset_cw;
 184             if (brw->attribs.Raster->light_twoside &&
 185                 key.fill_cw != CLIP_CULL)
 186                key.copy_bfc_cw = 1;
 187          }
 188       }
 189    }
 190 #else
 191    key.clip_mode = BRW_CLIPMODE_ACCEPT_ALL;
 192 #endif
 193
 194    if (!search_cache(brw, &key))
 195       compile_clip_prog( brw, &key );
 196 }
 197
 198 const struct brw_tracked_state brw_clip_prog = {
 199    .dirty = {
 200       .brw   = (BRW_NEW_RASTERIZER |
 201                 BRW_NEW_CLIP |
 202                 BRW_NEW_REDUCED_PRIMITIVE),
 203       .cache = CACHE_NEW_VS_PROG
 204    },
 205    .update = upload_clip_prog
 206 };