src/mesa/vbo/vbo_split_inplace.c

   1
   2 /*
   3  * Mesa 3-D graphics library
   4  * Version:  6.5
   5  *
   6  * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included
  16  * in all copies or substantial portions 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 MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  21  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  22  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  23  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  *
  25  * Authors:
  26  *    Keith Whitwell <keith@tungstengraphics.com>
  27  */
  28
  29
  30 #include "main/mtypes.h"
  31 #include "main/macros.h"
  32 #include "main/enums.h"
  33 #include "vbo_split.h"
  34
  35
  36 #define MAX_PRIM 32
  37
  38 /* Used for splitting without copying.
  39  */
  40 struct split_context {
  41    GLcontext *ctx;
  42    const struct gl_client_array **array;
  43    const struct _mesa_prim *prim;
  44    GLuint nr_prims;
  45    const struct _mesa_index_buffer *ib;
  46    GLuint min_index;
  47    GLuint max_index;
  48    vbo_draw_func draw;
  49
  50    const struct split_limits *limits;
  51
  52    struct _mesa_prim dstprim[MAX_PRIM];
  53    GLuint dstprim_nr;
  54 };
  55
  56
  57
  58
  59 static void flush_vertex( struct split_context *split )
  60 {
  61    GLuint min_index, max_index;
  62
  63    if (!split->dstprim_nr)
  64       return;
  65
  66    GLuint i;
  67    min_index = split->dstprim[0].start;
  68    max_index = min_index + split->dstprim[0].count - 1;
  69
  70    for (i = 1; i < split->dstprim_nr; i++) {
  71       GLuint tmp_min = split->dstprim[i].start;
  72       GLuint tmp_max = tmp_min + split->dstprim[i].count - 1;
  73
  74       if (tmp_min < min_index)
  75          min_index = tmp_min;
  76
  77       if (tmp_max > max_index)
  78          max_index = tmp_max;
  79    }
  80
  81    assert(max_index >= min_index);
  82
  83    split->draw( split->ctx,
  84                 split->array,
  85                 split->dstprim,
  86                 split->dstprim_nr,
  87                 NULL,
  88                 min_index,
  89                 max_index);
  90
  91    split->dstprim_nr = 0;
  92 }
  93
  94
  95 static struct _mesa_prim *next_outprim( struct split_context *split )
  96 {
  97    if (split->dstprim_nr == MAX_PRIM-1) {
  98       flush_vertex(split);
  99    }
 100
 101    {
 102       struct _mesa_prim *prim = &split->dstprim[split->dstprim_nr++];
 103       memset(prim, 0, sizeof(*prim));
 104       return prim;
 105    }
 106 }
 107
 108 static int align(int value, int alignment)
 109 {
 110    return (value + alignment - 1) & ~(alignment - 1);
 111 }
 112
 113
 114
 115 /* Break large primitives into smaller ones.  If not possible, convert
 116  * the primitive to indexed and pass to split_elts().
 117  */
 118 static void split_prims( struct split_context *split)
 119 {
 120    GLuint csr = 0;
 121    GLuint i;
 122
 123    for (i = 0; i < split->nr_prims; i++) {
 124       const struct _mesa_prim *prim = &split->prim[i];
 125       GLuint first, incr;
 126       GLboolean split_inplace = split_prim_inplace(prim->mode, &first, &incr);
 127       GLuint count;
 128
 129       /* Always wrap on an even numbered vertex to avoid problems with
 130        * triangle strips.
 131        */
 132       GLuint available = align(split->limits->max_verts - csr - 1, 2);
 133       assert(split->limits->max_verts >= csr);
 134
 135       if (prim->count < first)
 136          continue;
 137
 138       count = prim->count - (prim->count - first) % incr;
 139
 140
 141       if ((available < count && !split_inplace) ||
 142           (available < first && split_inplace)) {
 143          flush_vertex(split);
 144          csr = 0;
 145          available = align(split->limits->max_verts - csr - 1, 2);
 146       }
 147
 148       if (available >= count) {
 149          struct _mesa_prim *outprim = next_outprim(split);
 150          *outprim = *prim;
 151          csr += prim->count;
 152          available = align(split->limits->max_verts - csr - 1, 2);
 153       }
 154       else if (split_inplace) {
 155          GLuint j, nr;
 156
 157
 158          for (j = 0 ; j < count ; ) {
 159             GLuint remaining = count - j;
 160             struct _mesa_prim *outprim = next_outprim(split);
 161
 162             nr = MIN2( available, remaining );
 163
 164             nr -= (nr - first) % incr;
 165
 166             outprim->mode = prim->mode;
 167             outprim->begin = (j == 0 && prim->begin);
 168             outprim->end = (nr == remaining && prim->end);
 169             outprim->start = prim->start + j;
 170             outprim->count = nr;
 171
 172             if (nr == remaining) {
 173                /* Finished.
 174                 */
 175                j += nr;
 176                csr += nr;
 177                available = align(split->limits->max_verts - csr - 1, 2);
 178             }
 179             else {
 180                /* Wrapped the primitive:
 181                 */
 182                j += nr - (first - incr);
 183                flush_vertex(split);
 184                csr = 0;
 185                available = align(split->limits->max_verts - csr - 1, 2);
 186             }
 187          }
 188       }
 189       else if (split->ib == NULL) {
 190          /* XXX: could at least send the first max_verts off from the
 191           * inplace buffers.
 192           */
 193
 194          /* else convert to indexed primitive and pass to split_elts,
 195           * which will do the necessary copying and turn it back into a
 196           * vertex primitive for rendering...
 197           */
 198          struct _mesa_index_buffer ib;
 199          struct _mesa_prim tmpprim;
 200          GLuint *elts = malloc(count * sizeof(GLuint));
 201          GLuint j;
 202
 203          for (j = 0; j < count; j++)
 204             elts[j] = prim->start + j;
 205
 206          ib.count = count;
 207          ib.type = GL_UNSIGNED_INT;
 208          ib.obj = split->ctx->Shared->NullBufferObj;
 209          ib.ptr = elts;
 210
 211          tmpprim = *prim;
 212          tmpprim.indexed = 1;
 213          tmpprim.start = 0;
 214          tmpprim.count = count;
 215
 216          flush_vertex(split);
 217
 218          vbo_split_copy(split->ctx,
 219                         split->array,
 220                         &tmpprim, 1,
 221                         &ib,
 222                         split->draw,
 223                         split->limits);
 224
 225          free(elts);
 226       }
 227       else {
 228          flush_vertex(split);
 229
 230          vbo_split_copy(split->ctx,
 231                         split->array,
 232                         prim, 1,
 233                         split->ib,
 234                         split->draw,
 235                         split->limits);
 236       }
 237    }
 238
 239    flush_vertex(split);
 240 }
 241
 242
 243 void vbo_split_inplace( GLcontext *ctx,
 244                         const struct gl_client_array *arrays[],
 245                         const struct _mesa_prim *prim,
 246                         GLuint nr_prims,
 247                         const struct _mesa_index_buffer *ib,
 248                         GLuint min_index,
 249                         GLuint max_index,
 250                         vbo_draw_func draw,
 251                         const struct split_limits *limits )
 252 {
 253    struct split_context split;
 254
 255    memset(&split, 0, sizeof(split));
 256
 257    split.ctx = ctx;
 258    split.array = arrays;
 259    split.prim = prim;
 260    split.nr_prims = nr_prims;
 261    split.ib = ib;
 262    split.min_index = min_index;
 263    split.max_index = max_index;
 264    split.draw = draw;
 265    split.limits = limits;
 266
 267    split_prims( &split );
 268 }
 269
 270