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 boolean
 105 sp_vbuf_set_primitive(struct vbuf_render *vbr, unsigned prim)
 106 {
 107    struct softpipe_vbuf_render *cvbr = softpipe_vbuf_render(vbr);
 108    if (prim == PIPE_PRIM_TRIANGLES ||
 109        prim == PIPE_PRIM_LINES ||
 110        prim == PIPE_PRIM_POINTS) {
 111       cvbr->prim = prim;
 112       return TRUE;
 113    }
 114    else {
 115       return FALSE;
 116    }
 117
 118 }
 119
 120
 121 /**
 122  * Recalculate prim's determinant.
 123  * XXX is this needed?
 124  */
 125 static void
 126 calc_det(struct prim_header *header)
 127 {
 128    /* Window coords: */
 129    const float *v0 = header->v[0]->data[0];
 130    const float *v1 = header->v[1]->data[0];
 131    const float *v2 = header->v[2]->data[0];
 132
 133    /* edge vectors e = v0 - v2, f = v1 - v2 */
 134    const float ex = v0[0] - v2[0];
 135    const float ey = v0[1] - v2[1];
 136    const float fx = v1[0] - v2[0];
 137    const float fy = v1[1] - v2[1];
 138
 139    /* det = cross(e,f).z */
 140    header->det = ex * fy - ey * fx;
 141 }
 142
 143
 144 static void
 145 sp_vbuf_draw(struct vbuf_render *vbr, const ushort *indices, uint nr_indices)
 146 {
 147    struct softpipe_vbuf_render *cvbr = softpipe_vbuf_render(vbr);
 148    struct softpipe_context *softpipe = cvbr->softpipe;
 149    struct draw_stage *setup = softpipe->setup;
 150    struct prim_header prim;
 151    unsigned vertex_size = softpipe->vertex_info_vbuf.size * sizeof(float);
 152    unsigned i, j;
 153    void *vertex_buffer = cvbr->vertex_buffer;
 154
 155    prim.det = 0;
 156    prim.reset_line_stipple = 0;
 157    prim.edgeflags = 0;
 158    prim.pad = 0;
 159
 160    switch (cvbr->prim) {
 161    case PIPE_PRIM_TRIANGLES:
 162       for (i = 0; i < nr_indices; i += 3) {
 163          for (j = 0; j < 3; j++)
 164             prim.v[j] = (struct vertex_header *)((char *)vertex_buffer +
 165                                                  indices[i+j] * vertex_size);
 166
 167          calc_det(&prim);
 168          setup->tri( setup, &prim );
 169       }
 170       break;
 171
 172    case PIPE_PRIM_LINES:
 173       for (i = 0; i < nr_indices; i += 2) {
 174          for (j = 0; j < 2; j++)
 175             prim.v[j] = (struct vertex_header *)((char *)vertex_buffer +
 176                                                  indices[i+j] * vertex_size);
 177
 178          setup->line( setup, &prim );
 179       }
 180       break;
 181
 182    case PIPE_PRIM_POINTS:
 183       for (i = 0; i < nr_indices; i++) {
 184          prim.v[0] = (struct vertex_header *)((char *)vertex_buffer +
 185                                               indices[i] * vertex_size);
 186          setup->point( setup, &prim );
 187       }
 188       break;
 189    }
 190
 191    setup->flush( setup, 0 );
 192 }
 193
 194
 195 /**
 196  * This function is hit when the draw module is working in pass-through mode.
 197  * It's up to us to convert the vertex array into point/line/tri prims.
 198  */
 199 static void
 200 sp_vbuf_draw_arrays(struct vbuf_render *vbr, uint start, uint nr)
 201 {
 202    struct softpipe_vbuf_render *cvbr = softpipe_vbuf_render(vbr);
 203    struct softpipe_context *softpipe = cvbr->softpipe;
 204    struct draw_stage *setup = softpipe->setup;
 205    struct prim_header prim;
 206    const void *vertex_buffer = cvbr->vertex_buffer;
 207    const unsigned vertex_size = softpipe->vertex_info_vbuf.size * sizeof(float);
 208    unsigned i;
 209
 210    prim.det = 0;
 211    prim.reset_line_stipple = 0;
 212    prim.edgeflags = 0;
 213    prim.pad = 0;
 214
 215 #define VERTEX(I) \
 216    (struct vertex_header *) ((char *) vertex_buffer + (I) * vertex_size)
 217
 218    switch (cvbr->prim) {
 219    case PIPE_PRIM_POINTS:
 220       for (i = 0; i < nr; i++) {
 221          prim.v[0] = VERTEX(i);
 222          setup->point( setup, &prim );
 223       }
 224       break;
 225    case PIPE_PRIM_LINES:
 226       assert(nr % 2 == 0);
 227       for (i = 0; i < nr; i += 2) {
 228          prim.v[0] = VERTEX(i);
 229          prim.v[1] = VERTEX(i + 1);
 230          setup->line( setup, &prim );
 231       }
 232       break;
 233    case PIPE_PRIM_LINE_STRIP:
 234       for (i = 1; i < nr; i++) {
 235          prim.v[0] = VERTEX(i - 1);
 236          prim.v[1] = VERTEX(i);
 237          setup->line( setup, &prim );
 238       }
 239       break;
 240    case PIPE_PRIM_TRIANGLES:
 241       assert(nr % 3 == 0);
 242       for (i = 0; i < nr; i += 3) {
 243          prim.v[0] = VERTEX(i + 0);
 244          prim.v[1] = VERTEX(i + 1);
 245          prim.v[2] = VERTEX(i + 2);
 246          calc_det(&prim);
 247          setup->tri( setup, &prim );
 248       }
 249       break;
 250    case PIPE_PRIM_TRIANGLE_STRIP:
 251       assert(nr >= 3);
 252       for (i = 2; i < nr; i++) {
 253          prim.v[0] = VERTEX(i - 2);
 254          prim.v[1] = VERTEX(i - 1);
 255          prim.v[2] = VERTEX(i);
 256          calc_det(&prim);
 257          setup->tri( setup, &prim );
 258       }
 259       break;
 260    case PIPE_PRIM_TRIANGLE_FAN:
 261       assert(nr >= 3);
 262       for (i = 2; i < nr; i++) {
 263          prim.v[0] = VERTEX(0);
 264          prim.v[1] = VERTEX(i - 1);
 265          prim.v[2] = VERTEX(i);
 266          calc_det(&prim);
 267          setup->tri( setup, &prim );
 268       }
 269       break;
 270    case PIPE_PRIM_QUADS:
 271       assert(nr % 4 == 0);
 272       for (i = 0; i < nr; i += 4) {
 273          prim.v[0] = VERTEX(i + 0);
 274          prim.v[1] = VERTEX(i + 1);
 275          prim.v[2] = VERTEX(i + 2);
 276          calc_det(&prim);
 277          setup->tri( setup, &prim );
 278
 279          prim.v[0] = VERTEX(i + 0);
 280          prim.v[1] = VERTEX(i + 2);
 281          prim.v[2] = VERTEX(i + 3);
 282          calc_det(&prim);
 283          setup->tri( setup, &prim );
 284       }
 285       break;
 286    case PIPE_PRIM_QUAD_STRIP:
 287       assert(nr >= 4);
 288       for (i = 2; i < nr; i += 2) {
 289          prim.v[0] = VERTEX(i - 2);
 290          prim.v[1] = VERTEX(i);
 291          prim.v[2] = VERTEX(i + 1);
 292          calc_det(&prim);
 293          setup->tri( setup, &prim );
 294
 295          prim.v[0] = VERTEX(i - 2);
 296          prim.v[1] = VERTEX(i + 1);
 297          prim.v[2] = VERTEX(i - 1);
 298          calc_det(&prim);
 299          setup->tri( setup, &prim );
 300       }
 301       break;
 302    case PIPE_PRIM_POLYGON:
 303       /* draw as tri fan */
 304       for (i = 2; i < nr; i++) {
 305          prim.v[0] = VERTEX(0);
 306          prim.v[1] = VERTEX(i - 1);
 307          prim.v[2] = VERTEX(i);
 308          calc_det(&prim);
 309          setup->tri( setup, &prim );
 310       }
 311       break;
 312    default:
 313       /* XXX finish remaining prim types */
 314       assert(0);
 315    }
 316
 317 #undef VERTEX
 318 }
 319
 320
 321
 322 static void
 323 sp_vbuf_destroy(struct vbuf_render *vbr)
 324 {
 325    struct softpipe_vbuf_render *cvbr = softpipe_vbuf_render(vbr);
 326    cvbr->softpipe->vbuf_render = NULL;
 327    FREE(cvbr);
 328 }
 329
 330
 331 /**
 332  * Initialize the post-transform vertex buffer information for the given
 333  * context.
 334  */
 335 void
 336 sp_init_vbuf(struct softpipe_context *sp)
 337 {
 338    assert(sp->draw);
 339
 340    sp->vbuf_render = CALLOC_STRUCT(softpipe_vbuf_render);
 341
 342    sp->vbuf_render->base.max_indices = SP_MAX_VBUF_INDEXES;
 343    sp->vbuf_render->base.max_vertex_buffer_bytes = SP_MAX_VBUF_SIZE;
 344
 345    sp->vbuf_render->base.get_vertex_info = sp_vbuf_get_vertex_info;
 346    sp->vbuf_render->base.allocate_vertices = sp_vbuf_allocate_vertices;
 347    sp->vbuf_render->base.set_primitive = sp_vbuf_set_primitive;
 348    sp->vbuf_render->base.draw = sp_vbuf_draw;
 349    sp->vbuf_render->base.draw_arrays = sp_vbuf_draw_arrays;
 350    sp->vbuf_render->base.release_vertices = sp_vbuf_release_vertices;
 351    sp->vbuf_render->base.destroy = sp_vbuf_destroy;
 352
 353    sp->vbuf_render->softpipe = sp;
 354
 355    sp->vbuf = draw_vbuf_stage(sp->draw, &sp->vbuf_render->base);
 356
 357    draw_set_rasterize_stage(sp->draw, sp->vbuf);
 358
 359    draw_set_render(sp->draw, &sp->vbuf_render->base);
 360 }