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

   1 /*
   2  * Copyright © 2013 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  */
  23
  24 #include "brw_compiler.h"
  25 #include "brw_context.h"
  26 #include "compiler/nir/nir.h"
  27
  28 static char const *get_qual_name(int mode)
  29 {
  30    switch (mode) {
  31       case INTERP_MODE_NONE:          return "none";
  32       case INTERP_MODE_FLAT:          return "flat";
  33       case INTERP_MODE_SMOOTH:        return "smooth";
  34       case INTERP_MODE_NOPERSPECTIVE: return "nopersp";
  35       default:                             return "???";
  36    }
  37 }
  38
  39 static void
  40 gen4_frag_prog_set_interp_modes(struct gen4_fragment_program *prog,
  41                                 struct brw_vue_map *vue_map,
  42                                 unsigned location, unsigned slot_count,
  43                                 enum glsl_interp_mode interp)
  44 {
  45    for (unsigned k = 0; k < slot_count; k++) {
  46       unsigned slot = vue_map->varying_to_slot[location + k];
  47       if (slot != -1 && prog->interp_mode[slot] == INTERP_MODE_NONE) {
  48          prog->interp_mode[slot] = interp;
  49
  50          if (prog->interp_mode[slot] == INTERP_MODE_FLAT) {
  51             prog->contains_flat_varying = true;
  52          } else if (prog->interp_mode[slot] == INTERP_MODE_NOPERSPECTIVE) {
  53             prog->contains_noperspective_varying = true;
  54          }
  55       }
  56    }
  57 }
  58
  59 /* Set up interpolation modes for every element in the VUE */
  60 void
  61 brw_setup_vue_interpolation(struct brw_vue_map *vue_map, nir_shader *nir,
  62                             struct gl_program *prog,
  63                             const struct gen_device_info *devinfo)
  64 {
  65    struct gen4_fragment_program *fprog = (struct gen4_fragment_program *) prog;
  66
  67    /* Initialise interp_mode. INTERP_MODE_NONE == 0 */
  68    memset(fprog->interp_mode, 0, sizeof(fprog->interp_mode));
  69
  70    if (!vue_map)
  71       return;
  72
  73    /* HPOS always wants noperspective. setting it up here allows
  74     * us to not need special handling in the SF program.
  75     */
  76    unsigned pos_slot = vue_map->varying_to_slot[VARYING_SLOT_POS];
  77    if (pos_slot != -1) {;
  78       fprog->interp_mode[pos_slot] = INTERP_MODE_NOPERSPECTIVE;
  79       fprog->contains_noperspective_varying = true;
  80    }
  81
  82    foreach_list_typed(nir_variable, var, node, &nir->inputs) {
  83       unsigned location = var->data.location;
  84       unsigned slot_count = glsl_count_attribute_slots(var->type, false);
  85
  86       gen4_frag_prog_set_interp_modes(fprog, vue_map, location, slot_count,
  87                                       var->data.interpolation);
  88
  89       if (location == VARYING_SLOT_COL0 || location == VARYING_SLOT_COL1) {
  90          location = location + VARYING_SLOT_BFC0 - VARYING_SLOT_COL0;
  91          gen4_frag_prog_set_interp_modes(fprog, vue_map, location,
  92                                          slot_count, var->data.interpolation);
  93       }
  94    }
  95
  96    bool debug = false;
  97    if (debug) {
  98       fprintf(stderr, "VUE map:\n");
  99       for (int i = 0; i < vue_map->num_slots; i++) {
 100          int varying = vue_map->slot_to_varying[i];
 101          if (varying == -1) {
 102             fprintf(stderr, "%d: --\n", i);
 103             continue;
 104          }
 105
 106          fprintf(stderr, "%d: %d %s ofs %d\n",
 107                  i, varying,
 108                  get_qual_name(fprog->interp_mode[i]),
 109                  brw_vue_slot_to_offset(i));
 110       }
 111    }
 112 }