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 /**
  59  * Execute fragment shader for the four fragments in the quad.
  60  * \return TRUE if quad is alive, FALSE if all four pixels are killed
  61  */
  62 static inline boolean
  63 shade_quad(struct quad_stage *qs, struct quad_header *quad)
  64 {
  65    struct softpipe_context *softpipe = qs->softpipe;
  66    struct tgsi_exec_machine *machine = softpipe->fs_machine;
  67
  68    if (softpipe->active_statistics_queries) {
  69       softpipe->pipeline_statistics.ps_invocations +=
  70          util_bitcount(quad->inout.mask);
  71    }
  72
  73    /* run shader */
  74    machine->flatshade_color = softpipe->rasterizer->flatshade ? TRUE : FALSE;
  75    return softpipe->fs_variant->run( softpipe->fs_variant, machine, quad, softpipe->early_depth );
  76 }
  77
  78
  79
  80 static void
  81 coverage_quad(struct quad_stage *qs, struct quad_header *quad)
  82 {
  83    struct softpipe_context *softpipe = qs->softpipe;
  84    uint cbuf;
  85
  86    /* loop over colorbuffer outputs */
  87    for (cbuf = 0; cbuf < softpipe->framebuffer.nr_cbufs; cbuf++) {
  88       float (*quadColor)[4] = quad->output.color[cbuf];
  89       unsigned j;
  90       for (j = 0; j < TGSI_QUAD_SIZE; j++) {
  91          assert(quad->input.coverage[j] >= 0.0);
  92          assert(quad->input.coverage[j] <= 1.0);
  93          quadColor[3][j] *= quad->input.coverage[j];
  94       }
  95    }
  96 }
  97
  98
  99 /**
 100  * Shade/write an array of quads
 101  * Called via quad_stage::run()
 102  */
 103 static void
 104 shade_quads(struct quad_stage *qs,
 105             struct quad_header *quads[],
 106             unsigned nr)
 107 {
 108    struct softpipe_context *softpipe = qs->softpipe;
 109    struct tgsi_exec_machine *machine = softpipe->fs_machine;
 110    unsigned i, nr_quads = 0;
 111
 112    tgsi_exec_set_constant_buffers(machine, PIPE_MAX_CONSTANT_BUFFERS,
 113                          softpipe->mapped_constants[PIPE_SHADER_FRAGMENT],
 114                          softpipe->const_buffer_size[PIPE_SHADER_FRAGMENT]);
 115
 116    machine->InterpCoefs = quads[0]->coef;
 117
 118    for (i = 0; i < nr; i++) {
 119       /* Only omit this quad from the output list if all the fragments
 120        * are killed _AND_ it's not the first quad in the list.
 121        * The first quad is special in the (optimized) depth-testing code:
 122        * the quads' Z coordinates are step-wise interpolated with respect
 123        * to the first quad in the list.
 124        * For multi-pass algorithms we need to produce exactly the same
 125        * Z values in each pass.  If interpolation starts with different quads
 126        * we can get different Z values for the same (x,y).
 127        */
 128       if (!shade_quad(qs, quads[i]) && i > 0)
 129          continue; /* quad totally culled/killed */
 130
 131       if (/*do_coverage*/ 0)
 132          coverage_quad( qs, quads[i] );
 133
 134       quads[nr_quads++] = quads[i];
 135    }
 136
 137    if (nr_quads)
 138       qs->next->run(qs->next, quads, nr_quads);
 139 }
 140
 141
 142 /**
 143  * Per-primitive (or per-begin?) setup
 144  */
 145 static void
 146 shade_begin(struct quad_stage *qs)
 147 {
 148    qs->next->begin(qs->next);
 149 }
 150
 151
 152 static void
 153 shade_destroy(struct quad_stage *qs)
 154 {
 155    FREE( qs );
 156 }
 157
 158
 159 struct quad_stage *
 160 sp_quad_shade_stage( struct softpipe_context *softpipe )
 161 {
 162    struct quad_shade_stage *qss = CALLOC_STRUCT(quad_shade_stage);
 163    if (!qss)
 164       goto fail;
 165
 166    qss->stage.softpipe = softpipe;
 167    qss->stage.begin = shade_begin;
 168    qss->stage.run = shade_quads;
 169    qss->stage.destroy = shade_destroy;
 170
 171    return &qss->stage;
 172
 173 fail:
 174    FREE(qss);
 175    return NULL;
 176 }