src/gallium/drivers/softpipe/sp_quad_alpha_test.c

   1
   2 /**
   3  * quad alpha test
   4  */
   5
   6 #include "sp_context.h"
   7 #include "sp_quad.h"
   8 #include "sp_quad_pipe.h"
   9 #include "pipe/p_defines.h"
  10 #include "util/u_memory.h"
  11
  12 #define ALPHATEST( FUNC, COMP )                                         \
  13    static void                                                          \
  14    alpha_test_quads_##FUNC( struct quad_stage *qs,                      \
  15                            struct quad_header *quads[],                 \
  16                            unsigned nr )                                \
  17    {                                                                    \
  18       const float ref = qs->softpipe->depth_stencil->alpha.ref_value;   \
  19       const uint cbuf = 0; /* only output[0].alpha is tested */         \
  20       unsigned pass_nr = 0;                                             \
  21       unsigned i;                                                       \
  22                                                                         \
  23       for (i = 0; i < nr; i++) {                                        \
  24          const float *aaaa = quads[i]->output.color[cbuf][3];           \
  25          unsigned passMask = 0;                                         \
  26                                                                         \
  27          if (aaaa[0] COMP ref) passMask |= (1 << 0);                    \
  28          if (aaaa[1] COMP ref) passMask |= (1 << 1);                    \
  29          if (aaaa[2] COMP ref) passMask |= (1 << 2);                    \
  30          if (aaaa[3] COMP ref) passMask |= (1 << 3);                    \
  31                                                                         \
  32          quads[i]->inout.mask &= passMask;                              \
  33                                                                         \
  34          if (quads[i]->inout.mask)                                      \
  35             quads[pass_nr++] = quads[i];                                \
  36       }                                                                 \
  37                                                                         \
  38       if (pass_nr)                                                      \
  39          qs->next->run(qs->next, quads, pass_nr);                       \
  40    }
  41
  42
  43 ALPHATEST( LESS,     < )
  44 ALPHATEST( EQUAL,    == )
  45 ALPHATEST( LEQUAL,   <= )
  46 ALPHATEST( GREATER,  > )
  47 ALPHATEST( NOTEQUAL, != )
  48 ALPHATEST( GEQUAL,   >= )
  49
  50
  51 /* XXX: Incorporate into shader using KILP.
  52  */
  53 static void
  54 alpha_test_quad(struct quad_stage *qs,
  55                 struct quad_header *quads[],
  56                 unsigned nr)
  57 {
  58    switch (qs->softpipe->depth_stencil->alpha.func) {
  59    case PIPE_FUNC_LESS:
  60       alpha_test_quads_LESS( qs, quads, nr );
  61       break;
  62    case PIPE_FUNC_EQUAL:
  63       alpha_test_quads_EQUAL( qs, quads, nr );
  64       break;
  65    case PIPE_FUNC_LEQUAL:
  66       alpha_test_quads_LEQUAL( qs, quads, nr );
  67       break;
  68    case PIPE_FUNC_GREATER:
  69       alpha_test_quads_GREATER( qs, quads, nr );
  70       break;
  71    case PIPE_FUNC_NOTEQUAL:
  72       alpha_test_quads_NOTEQUAL( qs, quads, nr );
  73       break;
  74    case PIPE_FUNC_GEQUAL:
  75       alpha_test_quads_GEQUAL( qs, quads, nr );
  76       break;
  77    case PIPE_FUNC_ALWAYS:
  78       assert(0); /* should be caught earlier */
  79       qs->next->run(qs->next, quads, nr);
  80       break;
  81    case PIPE_FUNC_NEVER:
  82    default:
  83       assert(0); /* should be caught earlier */
  84       return;
  85    }
  86 }
  87
  88
  89 static void alpha_test_begin(struct quad_stage *qs)
  90 {
  91    qs->next->begin(qs->next);
  92 }
  93
  94
  95 static void alpha_test_destroy(struct quad_stage *qs)
  96 {
  97    FREE( qs );
  98 }
  99
 100
 101 struct quad_stage *
 102 sp_quad_alpha_test_stage( struct softpipe_context *softpipe )
 103 {
 104    struct quad_stage *stage = CALLOC_STRUCT(quad_stage);
 105
 106    stage->softpipe = softpipe;
 107    stage->begin = alpha_test_begin;
 108    stage->run = alpha_test_quad;
 109    stage->destroy = alpha_test_destroy;
 110
 111    return stage;
 112 }