src/mesa/pipe/softpipe/sp_quad_alpha_test.c

   1
   2 /**
   3  * quad alpha test
   4  */
   5
   6 #include "sp_context.h"
   7 #include "sp_headers.h"
   8 #include "sp_quad.h"
   9 #include "pipe/p_defines.h"
  10 #include "pipe/p_util.h"
  11
  12
  13 static void
  14 alpha_test_quad(struct quad_stage *qs, struct quad_header *quad)
  15 {
  16    struct softpipe_context *softpipe = qs->softpipe;
  17    const float ref = softpipe->alpha_test->ref;
  18    unsigned passMask = 0x0, j;
  19
  20    switch (softpipe->alpha_test->func) {
  21    case PIPE_FUNC_NEVER:
  22       quad->mask = 0x0;
  23       break;
  24    case PIPE_FUNC_LESS:
  25       /*
  26        * If mask were an array [4] we could do this SIMD-style:
  27        * passMask = (quad->outputs.color[3] <= vec4(ref));
  28        */
  29       for (j = 0; j < QUAD_SIZE; j++) {
  30          if (quad->outputs.color[3][j] < ref) {
  31             passMask |= (1 << j);
  32          }
  33       }
  34       break;
  35    case PIPE_FUNC_EQUAL:
  36       for (j = 0; j < QUAD_SIZE; j++) {
  37          if (quad->outputs.color[3][j] == ref) {
  38             passMask |= (1 << j);
  39          }
  40       }
  41       break;
  42    case PIPE_FUNC_LEQUAL:
  43       for (j = 0; j < QUAD_SIZE; j++) {
  44          if (quad->outputs.color[3][j] <= ref) {
  45             passMask |= (1 << j);
  46          }
  47       }
  48       break;
  49    case PIPE_FUNC_GREATER:
  50       for (j = 0; j < QUAD_SIZE; j++) {
  51          if (quad->outputs.color[3][j] > ref) {
  52             passMask |= (1 << j);
  53          }
  54       }
  55       break;
  56    case PIPE_FUNC_NOTEQUAL:
  57       for (j = 0; j < QUAD_SIZE; j++) {
  58          if (quad->outputs.color[3][j] != ref) {
  59             passMask |= (1 << j);
  60          }
  61       }
  62       break;
  63    case PIPE_FUNC_GEQUAL:
  64       for (j = 0; j < QUAD_SIZE; j++) {
  65          if (quad->outputs.color[3][j] >= ref) {
  66             passMask |= (1 << j);
  67          }
  68       }
  69       break;
  70    case PIPE_FUNC_ALWAYS:
  71       passMask = MASK_ALL;
  72       break;
  73    default:
  74       abort();
  75    }
  76
  77    quad->mask &= passMask;
  78
  79    if (quad->mask)
  80       qs->next->run(qs->next, quad);
  81 }
  82
  83
  84 static void alpha_test_begin(struct quad_stage *qs)
  85 {
  86    if (qs->next)
  87       qs->next->begin(qs->next);
  88 }
  89
  90
  91 static void alpha_test_destroy(struct quad_stage *qs)
  92 {
  93    FREE( qs );
  94 }
  95
  96
  97 struct quad_stage *
  98 sp_quad_alpha_test_stage( struct softpipe_context *softpipe )
  99 {
 100    struct quad_stage *stage = CALLOC_STRUCT(quad_stage);
 101
 102    stage->softpipe = softpipe;
 103    stage->begin = alpha_test_begin;
 104    stage->run = alpha_test_quad;
 105    stage->destroy = alpha_test_destroy;
 106
 107    return stage;
 108 }