src/mesa/pipe/draw/draw_vertex_shader.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28  /*
  29   * Authors:
  30   *   Keith Whitwell <keith@tungstengraphics.com>
  31   *   Brian Paul
  32   */
  33
  34 #include "pipe/p_util.h"
  35 #include "draw_private.h"
  36 #include "draw_context.h"
  37 #include "draw_vertex.h"
  38
  39 #include "pipe/tgsi/exec/tgsi_core.h"
  40
  41 static INLINE unsigned
  42 compute_clipmask(float cx, float cy, float cz, float cw)
  43 {
  44    unsigned mask = 0;
  45
  46    if (-cx + cw < 0) mask |= CLIP_RIGHT_BIT;
  47    if ( cx + cw < 0) mask |= CLIP_LEFT_BIT;
  48    if (-cy + cw < 0) mask |= CLIP_TOP_BIT;
  49    if ( cy + cw < 0) mask |= CLIP_BOTTOM_BIT;
  50    if (-cz + cw < 0) mask |= CLIP_FAR_BIT;
  51    if ( cz + cw < 0) mask |= CLIP_NEAR_BIT;
  52
  53    return mask;
  54 }
  55
  56
  57
  58
  59 #if !defined(XSTDCALL)
  60 #if defined(WIN32)
  61 #define XSTDCALL __stdcall
  62 #else
  63 #define XSTDCALL
  64 #endif
  65 #endif
  66
  67 typedef void (XSTDCALL *codegen_function) (
  68    const struct tgsi_exec_vector *input,
  69    struct tgsi_exec_vector *output,
  70    float (*constant)[4],
  71    struct tgsi_exec_vector *temporary );
  72
  73 /**
  74  * Transform vertices with the current vertex program/shader
  75  * Up to four vertices can be shaded at a time.
  76  * \param vbuffer  the input vertex data
  77  * \param elts  indexes of four input vertices
  78  * \param count  number of vertices to shade [1..4]
  79  * \param vOut  array of pointers to four output vertices
  80  */
  81 static void
  82 run_vertex_program(struct draw_context *draw,
  83                    unsigned elts[4], unsigned count,
  84                    struct vertex_header *vOut[])
  85 {
  86    struct tgsi_exec_machine machine;
  87    unsigned int j;
  88
  89    ALIGN16_DECL(struct tgsi_exec_vector, inputs, PIPE_ATTRIB_MAX);
  90    ALIGN16_DECL(struct tgsi_exec_vector, outputs, PIPE_ATTRIB_MAX);
  91    const float *scale = draw->viewport.scale;
  92    const float *trans = draw->viewport.translate;
  93
  94    assert(count <= 4);
  95    assert(draw->vertex_shader.output_semantic_name[0]
  96           == TGSI_SEMANTIC_POSITION);
  97
  98 #ifdef DEBUG
  99    memset( &machine, 0, sizeof( machine ) );
 100 #endif
 101
 102    /* init machine state */
 103    tgsi_exec_machine_init(&machine,
 104                           draw->vertex_shader.tokens,
 105                           PIPE_MAX_SAMPLERS,
 106                           NULL /*samplers*/ );
 107
 108    /* Consts does not require 16 byte alignment. */
 109    machine.Consts = (float (*)[4]) draw->mapped_constants;
 110
 111    machine.Inputs = ALIGN16_ASSIGN(inputs);
 112    machine.Outputs = ALIGN16_ASSIGN(outputs);
 113
 114    draw_vertex_fetch( draw, &machine, elts, count );
 115
 116    /* run shader */
 117    if( draw->vertex_shader.executable != NULL ) {
 118       codegen_function func = (codegen_function) draw->vertex_shader.executable;
 119       func(
 120          machine.Inputs,
 121          machine.Outputs,
 122          machine.Consts,
 123          machine.Temps );
 124    }
 125    else {
 126       tgsi_exec_machine_run( &machine );
 127    }
 128
 129
 130    /* store machine results */
 131    for (j = 0; j < count; j++) {
 132       unsigned slot;
 133       float x, y, z, w;
 134
 135       /* Handle attr[0] (position) specially: */
 136       x = vOut[j]->clip[0] = machine.Outputs[0].xyzw[0].f[j];
 137       y = vOut[j]->clip[1] = machine.Outputs[0].xyzw[1].f[j];
 138       z = vOut[j]->clip[2] = machine.Outputs[0].xyzw[2].f[j];
 139       w = vOut[j]->clip[3] = machine.Outputs[0].xyzw[3].f[j];
 140
 141       vOut[j]->clipmask = compute_clipmask(x, y, z, w) | draw->user_clipmask;
 142       vOut[j]->edgeflag = 1;
 143
 144       /* divide by w */
 145       w = 1.0f / w;
 146       x *= w;
 147       y *= w;
 148       z *= w;
 149
 150       /* Viewport mapping */
 151       vOut[j]->data[0][0] = x * scale[0] + trans[0];
 152       vOut[j]->data[0][1] = y * scale[1] + trans[1];
 153       vOut[j]->data[0][2] = z * scale[2] + trans[2];
 154       vOut[j]->data[0][3] = w;
 155
 156       /* Remaining attributes are packed into sequential post-transform
 157        * vertex attrib slots.
 158        * Skip 0 since we just did it above.
 159        * Subtract two because of the VERTEX_HEADER, CLIP_POS attribs.
 160        */
 161       for (slot = 1; slot < draw->vertex_info.num_attribs - 2; slot++) {
 162          vOut[j]->data[slot][0] = machine.Outputs[slot].xyzw[0].f[j];
 163          vOut[j]->data[slot][1] = machine.Outputs[slot].xyzw[1].f[j];
 164          vOut[j]->data[slot][2] = machine.Outputs[slot].xyzw[2].f[j];
 165          vOut[j]->data[slot][3] = machine.Outputs[slot].xyzw[3].f[j];
 166          /*
 167          printf("output %d: %f %f %f %f\n", slot,
 168                 vOut[j]->data[slot][0],
 169                 vOut[j]->data[slot][1],
 170                 vOut[j]->data[slot][2],
 171                 vOut[j]->data[slot][3]);
 172          */
 173       }
 174    } /* loop over vertices */
 175 }
 176
 177
 178 /**
 179  * Called by the draw module when the vertx cache needs to be flushed.
 180  * This involves running the vertex shader.
 181  */
 182 void draw_vertex_shader_queue_flush( struct draw_context *draw )
 183 {
 184    unsigned i, j;
 185
 186 //   fprintf(stderr, " q(%d) ", draw->vs.queue_nr );
 187
 188    /* run vertex shader on vertex cache entries, four per invokation */
 189    for (i = 0; i < draw->vs.queue_nr; i += 4) {
 190       struct vertex_header *dests[4];
 191       unsigned elts[4];
 192       int n;
 193
 194       for (j = 0; j < 4; j++) {
 195          elts[j] = draw->vs.queue[i + j].elt;
 196          dests[j] = draw->vs.queue[i + j].dest;
 197       }
 198
 199       n = MIN2(4, draw->vs.queue_nr - i);
 200       assert(n > 0);
 201       assert(n <= 4);
 202
 203       run_vertex_program(draw, elts, n, dests);
 204    }
 205
 206    draw->vs.queue_nr = 0;
 207 }
 208