src/gallium/auxiliary/draw/draw_pt_vsplit.c

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright 2007-2008 VMware, Inc.
   5  * Copyright (C) 2010 LunarG Inc.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  22  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  23  * DEALINGS IN THE SOFTWARE.
  24  */
  25
  26 #include "util/u_math.h"
  27 #include "util/u_memory.h"
  28
  29 #include "draw/draw_context.h"
  30 #include "draw/draw_private.h"
  31 #include "draw/draw_pt.h"
  32
  33 #define SEGMENT_SIZE 1024
  34 #define MAP_SIZE     256
  35
  36 /* The largest possible index within an index buffer */
  37 #define MAX_ELT_IDX 0xffffffff
  38
  39 struct vsplit_frontend {
  40    struct draw_pt_front_end base;
  41    struct draw_context *draw;
  42
  43    unsigned prim;
  44
  45    struct draw_pt_middle_end *middle;
  46
  47    unsigned max_vertices;
  48    ushort segment_size;
  49
  50    /* buffers for splitting */
  51    unsigned fetch_elts[SEGMENT_SIZE];
  52    ushort draw_elts[SEGMENT_SIZE];
  53    ushort identity_draw_elts[SEGMENT_SIZE];
  54
  55    struct {
  56       /* map a fetch element to a draw element */
  57       unsigned fetches[MAP_SIZE];
  58       ushort draws[MAP_SIZE];
  59       boolean has_max_fetch;
  60
  61       ushort num_fetch_elts;
  62       ushort num_draw_elts;
  63    } cache;
  64 };
  65
  66
  67 static void
  68 vsplit_clear_cache(struct vsplit_frontend *vsplit)
  69 {
  70    memset(vsplit->cache.fetches, 0xff, sizeof(vsplit->cache.fetches));
  71    vsplit->cache.has_max_fetch = FALSE;
  72    vsplit->cache.num_fetch_elts = 0;
  73    vsplit->cache.num_draw_elts = 0;
  74 }
  75
  76 static void
  77 vsplit_flush_cache(struct vsplit_frontend *vsplit, unsigned flags)
  78 {
  79    vsplit->middle->run(vsplit->middle,
  80          vsplit->fetch_elts, vsplit->cache.num_fetch_elts,
  81          vsplit->draw_elts, vsplit->cache.num_draw_elts, flags);
  82 }
  83
  84 /**
  85  * Add a fetch element and add it to the draw elements.
  86  */
  87 static inline void
  88 vsplit_add_cache(struct vsplit_frontend *vsplit, unsigned fetch)
  89 {
  90    unsigned hash;
  91
  92    hash = fetch % MAP_SIZE;
  93
  94    /* If the value isn't in the cache or it's an overflow due to the
  95     * element bias */
  96    if (vsplit->cache.fetches[hash] != fetch) {
  97       /* update cache */
  98       vsplit->cache.fetches[hash] = fetch;
  99       vsplit->cache.draws[hash] = vsplit->cache.num_fetch_elts;
 100
 101       /* add fetch */
 102       assert(vsplit->cache.num_fetch_elts < vsplit->segment_size);
 103       vsplit->fetch_elts[vsplit->cache.num_fetch_elts++] = fetch;
 104    }
 105
 106    vsplit->draw_elts[vsplit->cache.num_draw_elts++] = vsplit->cache.draws[hash];
 107 }
 108
 109 /**
 110  * Returns the base index to the elements array.
 111  * The value is checked for integer overflow (not sure it can happen?).
 112  */
 113 static inline unsigned
 114 vsplit_get_base_idx(unsigned start, unsigned fetch)
 115 {
 116    return draw_overflow_uadd(start, fetch, MAX_ELT_IDX);
 117 }
 118
 119 /*
 120  * The final element index is just element index plus element bias.
 121  */
 122 #define VSPLIT_CREATE_IDX(elts, start, fetch, elt_bias)    \
 123    unsigned elt_idx;                                       \
 124    elt_idx = vsplit_get_base_idx(start, fetch);            \
 125    elt_idx = (unsigned)((int)(DRAW_GET_IDX(elts, elt_idx)) + (int)elt_bias);
 126
 127
 128 static inline void
 129 vsplit_add_cache_ubyte(struct vsplit_frontend *vsplit, const ubyte *elts,
 130                        unsigned start, unsigned fetch, int elt_bias)
 131 {
 132    struct draw_context *draw = vsplit->draw;
 133    VSPLIT_CREATE_IDX(elts, start, fetch, elt_bias);
 134    /* unlike the uint case this can only happen with elt_bias */
 135    if (elt_bias && elt_idx == DRAW_MAX_FETCH_IDX && !vsplit->cache.has_max_fetch) {
 136       unsigned hash = elt_idx % MAP_SIZE;
 137       vsplit->cache.fetches[hash] = 0;
 138       vsplit->cache.has_max_fetch = TRUE;
 139    }
 140    vsplit_add_cache(vsplit, elt_idx);
 141 }
 142
 143 static inline void
 144 vsplit_add_cache_ushort(struct vsplit_frontend *vsplit, const ushort *elts,
 145                        unsigned start, unsigned fetch, int elt_bias)
 146 {
 147    struct draw_context *draw = vsplit->draw;
 148    VSPLIT_CREATE_IDX(elts, start, fetch, elt_bias);
 149    /* unlike the uint case this can only happen with elt_bias */
 150    if (elt_bias && elt_idx == DRAW_MAX_FETCH_IDX && !vsplit->cache.has_max_fetch) {
 151       unsigned hash = elt_idx % MAP_SIZE;
 152       vsplit->cache.fetches[hash] = 0;
 153       vsplit->cache.has_max_fetch = TRUE;
 154    }
 155    vsplit_add_cache(vsplit, elt_idx);
 156 }
 157
 158
 159 /**
 160  * Add a fetch element and add it to the draw elements.  The fetch element is
 161  * in full range (uint).
 162  */
 163 static inline void
 164 vsplit_add_cache_uint(struct vsplit_frontend *vsplit, const uint *elts,
 165                       unsigned start, unsigned fetch, int elt_bias)
 166 {
 167    struct draw_context *draw = vsplit->draw;
 168    VSPLIT_CREATE_IDX(elts, start, fetch, elt_bias);
 169    /* Take care for DRAW_MAX_FETCH_IDX (since cache is initialized to -1). */
 170    if (elt_idx == DRAW_MAX_FETCH_IDX && !vsplit->cache.has_max_fetch) {
 171       unsigned hash = elt_idx % MAP_SIZE;
 172       /* force update - any value will do except DRAW_MAX_FETCH_IDX */
 173       vsplit->cache.fetches[hash] = 0;
 174       vsplit->cache.has_max_fetch = TRUE;
 175    }
 176    vsplit_add_cache(vsplit, elt_idx);
 177 }
 178
 179
 180 #define FUNC vsplit_run_linear
 181 #include "draw_pt_vsplit_tmp.h"
 182
 183 #define FUNC vsplit_run_ubyte
 184 #define ELT_TYPE ubyte
 185 #define ADD_CACHE(vsplit, ib, start, fetch, bias) vsplit_add_cache_ubyte(vsplit,ib,start,fetch,bias)
 186 #include "draw_pt_vsplit_tmp.h"
 187
 188 #define FUNC vsplit_run_ushort
 189 #define ELT_TYPE ushort
 190 #define ADD_CACHE(vsplit, ib, start, fetch, bias) vsplit_add_cache_ushort(vsplit,ib,start,fetch, bias)
 191 #include "draw_pt_vsplit_tmp.h"
 192
 193 #define FUNC vsplit_run_uint
 194 #define ELT_TYPE uint
 195 #define ADD_CACHE(vsplit, ib, start, fetch, bias) vsplit_add_cache_uint(vsplit, ib, start, fetch, bias)
 196 #include "draw_pt_vsplit_tmp.h"
 197
 198
 199 static void vsplit_prepare(struct draw_pt_front_end *frontend,
 200                            unsigned in_prim,
 201                            struct draw_pt_middle_end *middle,
 202                            unsigned opt)
 203 {
 204    struct vsplit_frontend *vsplit = (struct vsplit_frontend *) frontend;
 205
 206    switch (vsplit->draw->pt.user.eltSize) {
 207    case 0:
 208       vsplit->base.run = vsplit_run_linear;
 209       break;
 210    case 1:
 211       vsplit->base.run = vsplit_run_ubyte;
 212       break;
 213    case 2:
 214       vsplit->base.run = vsplit_run_ushort;
 215       break;
 216    case 4:
 217       vsplit->base.run = vsplit_run_uint;
 218       break;
 219    default:
 220       assert(0);
 221       break;
 222    }
 223
 224    /* split only */
 225    vsplit->prim = in_prim;
 226
 227    vsplit->middle = middle;
 228    middle->prepare(middle, vsplit->prim, opt, &vsplit->max_vertices);
 229
 230    vsplit->segment_size = MIN2(SEGMENT_SIZE, vsplit->max_vertices);
 231 }
 232
 233
 234 static void vsplit_flush(struct draw_pt_front_end *frontend, unsigned flags)
 235 {
 236    struct vsplit_frontend *vsplit = (struct vsplit_frontend *) frontend;
 237
 238    if (flags & DRAW_FLUSH_STATE_CHANGE) {
 239       vsplit->middle->finish(vsplit->middle);
 240       vsplit->middle = NULL;
 241    }
 242 }
 243
 244
 245 static void vsplit_destroy(struct draw_pt_front_end *frontend)
 246 {
 247    FREE(frontend);
 248 }
 249
 250
 251 struct draw_pt_front_end *draw_pt_vsplit(struct draw_context *draw)
 252 {
 253    struct vsplit_frontend *vsplit = CALLOC_STRUCT(vsplit_frontend);
 254    ushort i;
 255
 256    if (!vsplit)
 257       return NULL;
 258
 259    vsplit->base.prepare = vsplit_prepare;
 260    vsplit->base.run     = NULL;
 261    vsplit->base.flush   = vsplit_flush;
 262    vsplit->base.destroy = vsplit_destroy;
 263    vsplit->draw = draw;
 264
 265    for (i = 0; i < SEGMENT_SIZE; i++)
 266       vsplit->identity_draw_elts[i] = i;
 267
 268    return &vsplit->base;
 269 }