src/gallium/drivers/softpipe/sp_prim_vbuf.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  * Post-transform vertex buffering.  This is an optional part of the
  30  * softpipe rendering pipeline.
  31  * Probably not desired in general, but useful for testing/debuggin.
  32  * Enabled/Disabled with SP_VBUF env var.
  33  *
  34  * Authors
  35  *  Brian Paul
  36  */
  37
  38
  39 #include "sp_context.h"
  40 #include "sp_state.h"
  41 #include "sp_prim_vbuf.h"
  42 #include "draw/draw_context.h"
  43 #include "draw/draw_private.h"
  44 #include "draw/draw_vbuf.h"
  45
  46
  47 #define SP_MAX_VBUF_INDEXES 1024
  48 #define SP_MAX_VBUF_SIZE    4096
  49
  50
  51 /**
  52  * Subclass of vbuf_render.
  53  */
  54 struct softpipe_vbuf_render
  55 {
  56    struct vbuf_render base;
  57    struct softpipe_context *softpipe;
  58    uint prim;
  59    uint vertex_size;
  60    void *vertex_buffer;
  61 };
  62
  63
  64 /** cast wrapper */
  65 static struct softpipe_vbuf_render *
  66 softpipe_vbuf_render(struct vbuf_render *vbr)
  67 {
  68    return (struct softpipe_vbuf_render *) vbr;
  69 }
  70
  71
  72
  73 static const struct vertex_info *
  74 sp_vbuf_get_vertex_info(struct vbuf_render *vbr)
  75 {
  76    struct softpipe_vbuf_render *cvbr = softpipe_vbuf_render(vbr);
  77    return softpipe_get_vbuf_vertex_info(cvbr->softpipe);
  78 }
  79
  80
  81 static void *
  82 sp_vbuf_allocate_vertices(struct vbuf_render *vbr,
  83                             ushort vertex_size, ushort nr_vertices)
  84 {
  85    struct softpipe_vbuf_render *cvbr = softpipe_vbuf_render(vbr);
  86    assert(!cvbr->vertex_buffer);
  87    cvbr->vertex_buffer = align_malloc(vertex_size * nr_vertices, 16);
  88    cvbr->vertex_size = vertex_size;
  89    return cvbr->vertex_buffer;
  90 }
  91
  92
  93 static void
  94 sp_vbuf_release_vertices(struct vbuf_render *vbr, void *vertices,
  95                            unsigned vertex_size, unsigned vertices_used)
  96 {
  97    struct softpipe_vbuf_render *cvbr = softpipe_vbuf_render(vbr);
  98    align_free(vertices);
  99    assert(vertices == cvbr->vertex_buffer);
 100    cvbr->vertex_buffer = NULL;
 101 }
 102
 103
 104 static void
 105 sp_vbuf_set_primitive(struct vbuf_render *vbr, unsigned prim)
 106 {
 107    struct softpipe_vbuf_render *cvbr = softpipe_vbuf_render(vbr);
 108    cvbr->prim = prim;
 109 }
 110
 111
 112 /**
 113  * Recalculate prim's determinant.
 114  * XXX is this needed?
 115  */
 116 static void
 117 calc_det(struct prim_header *header)
 118 {
 119    /* Window coords: */
 120    const float *v0 = header->v[0]->data[0];
 121    const float *v1 = header->v[1]->data[0];
 122    const float *v2 = header->v[2]->data[0];
 123
 124    /* edge vectors e = v0 - v2, f = v1 - v2 */
 125    const float ex = v0[0] - v2[0];
 126    const float ey = v0[1] - v2[1];
 127    const float fx = v1[0] - v2[0];
 128    const float fy = v1[1] - v2[1];
 129
 130    /* det = cross(e,f).z */
 131    header->det = ex * fy - ey * fx;
 132 }
 133
 134
 135 static void
 136 sp_vbuf_draw(struct vbuf_render *vbr, const ushort *indices, uint nr_indices)
 137 {
 138    struct softpipe_vbuf_render *cvbr = softpipe_vbuf_render(vbr);
 139    struct softpipe_context *softpipe = cvbr->softpipe;
 140    struct draw_stage *setup = softpipe->setup;
 141    struct prim_header prim;
 142    unsigned vertex_size = softpipe->vertex_info_vbuf.size * sizeof(float);
 143    unsigned i, j;
 144    void *vertex_buffer = cvbr->vertex_buffer;
 145
 146    prim.det = 0;
 147    prim.reset_line_stipple = 0;
 148    prim.edgeflags = 0;
 149    prim.pad = 0;
 150
 151    switch (cvbr->prim) {
 152    case PIPE_PRIM_TRIANGLES:
 153       for (i = 0; i < nr_indices; i += 3) {
 154          for (j = 0; j < 3; j++)
 155             prim.v[j] = (struct vertex_header *)((char *)vertex_buffer +
 156                                                  indices[i+j] * vertex_size);
 157
 158          calc_det(&prim);
 159          setup->tri( setup, &prim );
 160       }
 161       break;
 162
 163    case PIPE_PRIM_LINES:
 164       for (i = 0; i < nr_indices; i += 2) {
 165          for (j = 0; j < 2; j++)
 166             prim.v[j] = (struct vertex_header *)((char *)vertex_buffer +
 167                                                  indices[i+j] * vertex_size);
 168
 169          setup->line( setup, &prim );
 170       }
 171       break;
 172
 173    case PIPE_PRIM_POINTS:
 174       for (i = 0; i < nr_indices; i++) {
 175          prim.v[0] = (struct vertex_header *)((char *)vertex_buffer +
 176                                               indices[i] * vertex_size);
 177          setup->point( setup, &prim );
 178       }
 179       break;
 180    }
 181
 182    setup->flush( setup, 0 );
 183 }
 184
 185
 186 static void
 187 sp_vbuf_destroy(struct vbuf_render *vbr)
 188 {
 189    struct softpipe_vbuf_render *cvbr = softpipe_vbuf_render(vbr);
 190    cvbr->softpipe->vbuf_render = NULL;
 191    FREE(cvbr);
 192 }
 193
 194
 195 /**
 196  * Initialize the post-transform vertex buffer information for the given
 197  * context.
 198  */
 199 void
 200 sp_init_vbuf(struct softpipe_context *sp)
 201 {
 202    assert(sp->draw);
 203
 204    sp->vbuf_render = CALLOC_STRUCT(softpipe_vbuf_render);
 205
 206    sp->vbuf_render->base.max_indices = SP_MAX_VBUF_INDEXES;
 207    sp->vbuf_render->base.max_vertex_buffer_bytes = SP_MAX_VBUF_SIZE;
 208
 209    sp->vbuf_render->base.get_vertex_info = sp_vbuf_get_vertex_info;
 210    sp->vbuf_render->base.allocate_vertices = sp_vbuf_allocate_vertices;
 211    sp->vbuf_render->base.set_primitive = sp_vbuf_set_primitive;
 212    sp->vbuf_render->base.draw = sp_vbuf_draw;
 213    sp->vbuf_render->base.release_vertices = sp_vbuf_release_vertices;
 214    sp->vbuf_render->base.destroy = sp_vbuf_destroy;
 215
 216    sp->vbuf_render->softpipe = sp;
 217
 218    sp->vbuf = draw_vbuf_stage(sp->draw, &sp->vbuf_render->base);
 219
 220    draw_set_rasterize_stage(sp->draw, sp->vbuf);
 221 }