src/gallium/drivers/softpipe/sp_quad_fs.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 VMware, Inc.
   4  * All Rights Reserved.
   5  * Copyright 2008 VMware, Inc.  All rights reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the
   9  * "Software"), to deal in the Software without restriction, including
  10  * without limitation the rights to use, copy, modify, merge, publish,
  11  * distribute, sub license, and/or sell copies of the Software, and to
  12  * permit persons to whom the Software is furnished to do so, subject to
  13  * the following conditions:
  14  *
  15  * The above copyright notice and this permission notice (including the
  16  * next paragraph) shall be included in all copies or substantial portions
  17  * of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  21  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  22  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
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  24  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  25  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  26  *
  27  **************************************************************************/
  28
  29 /* Vertices are just an array of floats, with all the attributes
  30  * packed.  We currently assume a layout like:
  31  *
  32  * attr[0][0..3] - window position
  33  * attr[1..n][0..3] - remaining attributes.
  34  *
  35  * Attributes are assumed to be 4 floats wide but are packed so that
  36  * all the enabled attributes run contiguously.
  37  */
  38
  39 #include "util/u_math.h"
  40 #include "util/u_memory.h"
  41 #include "pipe/p_defines.h"
  42 #include "pipe/p_shader_tokens.h"
  43
  44 #include "sp_context.h"
  45 #include "sp_state.h"
  46 #include "sp_quad.h"
  47 #include "sp_quad_pipe.h"
  48
  49
  50 struct quad_shade_stage
  51 {
  52    struct quad_stage stage;  /**< base class */
  53
  54    /* no other fields at this time */
  55 };
  56
  57
  58 /** cast wrapper */
  59 static INLINE struct quad_shade_stage *
  60 quad_shade_stage(struct quad_stage *qs)
  61 {
  62    return (struct quad_shade_stage *) qs;
  63 }
  64
  65
  66 /**
  67  * Execute fragment shader for the four fragments in the quad.
  68  * \return TRUE if quad is alive, FALSE if all four pixels are killed
  69  */
  70 static INLINE boolean
  71 shade_quad(struct quad_stage *qs, struct quad_header *quad)
  72 {
  73    struct softpipe_context *softpipe = qs->softpipe;
  74    struct tgsi_exec_machine *machine = softpipe->fs_machine;
  75
  76    if (softpipe->active_statistics_queries) {
  77       softpipe->pipeline_statistics.ps_invocations +=
  78          util_bitcount(quad->inout.mask);
  79    }
  80
  81    /* run shader */
  82    machine->flatshade_color = softpipe->rasterizer->flatshade ? TRUE : FALSE;
  83    return softpipe->fs_variant->run( softpipe->fs_variant, machine, quad );
  84 }
  85
  86
  87
  88 static void
  89 coverage_quad(struct quad_stage *qs, struct quad_header *quad)
  90 {
  91    struct softpipe_context *softpipe = qs->softpipe;
  92    uint cbuf;
  93
  94    /* loop over colorbuffer outputs */
  95    for (cbuf = 0; cbuf < softpipe->framebuffer.nr_cbufs; cbuf++) {
  96       float (*quadColor)[4] = quad->output.color[cbuf];
  97       unsigned j;
  98       for (j = 0; j < TGSI_QUAD_SIZE; j++) {
  99          assert(quad->input.coverage[j] >= 0.0);
 100          assert(quad->input.coverage[j] <= 1.0);
 101          quadColor[3][j] *= quad->input.coverage[j];
 102       }
 103    }
 104 }
 105
 106
 107 /**
 108  * Shade/write an array of quads
 109  * Called via quad_stage::run()
 110  */
 111 static void
 112 shade_quads(struct quad_stage *qs,
 113             struct quad_header *quads[],
 114             unsigned nr)
 115 {
 116    struct softpipe_context *softpipe = qs->softpipe;
 117    struct tgsi_exec_machine *machine = softpipe->fs_machine;
 118    unsigned i, nr_quads = 0;
 119
 120    tgsi_exec_set_constant_buffers(machine, PIPE_MAX_CONSTANT_BUFFERS,
 121                          softpipe->mapped_constants[PIPE_SHADER_FRAGMENT],
 122                          softpipe->const_buffer_size[PIPE_SHADER_FRAGMENT]);
 123
 124    machine->InterpCoefs = quads[0]->coef;
 125
 126    for (i = 0; i < nr; i++) {
 127       /* Only omit this quad from the output list if all the fragments
 128        * are killed _AND_ it's not the first quad in the list.
 129        * The first quad is special in the (optimized) depth-testing code:
 130        * the quads' Z coordinates are step-wise interpolated with respect
 131        * to the first quad in the list.
 132        * For multi-pass algorithms we need to produce exactly the same
 133        * Z values in each pass.  If interpolation starts with different quads
 134        * we can get different Z values for the same (x,y).
 135        */
 136       if (!shade_quad(qs, quads[i]) && i > 0)
 137          continue; /* quad totally culled/killed */
 138
 139       if (/*do_coverage*/ 0)
 140          coverage_quad( qs, quads[i] );
 141
 142       quads[nr_quads++] = quads[i];
 143    }
 144
 145    if (nr_quads)
 146       qs->next->run(qs->next, quads, nr_quads);
 147 }
 148
 149
 150 /**
 151  * Per-primitive (or per-begin?) setup
 152  */
 153 static void
 154 shade_begin(struct quad_stage *qs)
 155 {
 156    qs->next->begin(qs->next);
 157 }
 158
 159
 160 static void
 161 shade_destroy(struct quad_stage *qs)
 162 {
 163    FREE( qs );
 164 }
 165
 166
 167 struct quad_stage *
 168 sp_quad_shade_stage( struct softpipe_context *softpipe )
 169 {
 170    struct quad_shade_stage *qss = CALLOC_STRUCT(quad_shade_stage);
 171    if (!qss)
 172       goto fail;
 173
 174    qss->stage.softpipe = softpipe;
 175    qss->stage.begin = shade_begin;
 176    qss->stage.run = shade_quads;
 177    qss->stage.destroy = shade_destroy;
 178
 179    return &qss->stage;
 180
 181 fail:
 182    FREE(qss);
 183    return NULL;
 184 }