src/gallium/auxiliary/draw/draw_prim_assembler.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2013 VMware, Inc.
   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 VMWARE 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 #include "draw_prim_assembler.h"
  29
  30 #include "draw_fs.h"
  31 #include "draw_gs.h"
  32 #include "draw_tess.h"
  33 #include "util/u_debug.h"
  34 #include "util/u_memory.h"
  35 #include "util/u_prim.h"
  36
  37 #include "pipe/p_defines.h"
  38
  39 struct draw_assembler
  40 {
  41    struct draw_context *draw;
  42
  43    struct draw_prim_info *output_prims;
  44    struct draw_vertex_info *output_verts;
  45
  46    const struct draw_prim_info *input_prims;
  47    const struct draw_vertex_info *input_verts;
  48
  49    boolean needs_primid;
  50    int primid_slot;
  51    unsigned primid;
  52
  53    unsigned num_prims;
  54 };
  55
  56
  57 static boolean
  58 needs_primid(const struct draw_context *draw)
  59 {
  60    const struct draw_fragment_shader *fs = draw->fs.fragment_shader;
  61    const struct draw_geometry_shader *gs = draw->gs.geometry_shader;
  62    const struct draw_tess_eval_shader *tes = draw->tes.tess_eval_shader;
  63    if (fs && fs->info.uses_primid) {
  64       if (gs)
  65          return !gs->info.uses_primid;
  66       else if (tes)
  67          return !tes->info.uses_primid;
  68       else
  69          return TRUE;
  70    }
  71    return FALSE;
  72 }
  73
  74 boolean
  75 draw_prim_assembler_is_required(const struct draw_context *draw,
  76                                 const struct draw_prim_info *prim_info,
  77                                 const struct draw_vertex_info *vert_info)
  78 {
  79    /* viewport index requires primitive boundaries to get correct vertex */
  80    if (draw_current_shader_uses_viewport_index(draw))
  81       return TRUE;
  82    switch (prim_info->prim) {
  83    case PIPE_PRIM_LINES_ADJACENCY:
  84    case PIPE_PRIM_LINE_STRIP_ADJACENCY:
  85    case PIPE_PRIM_TRIANGLES_ADJACENCY:
  86    case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
  87       return TRUE;
  88    default:
  89       return needs_primid(draw);
  90    }
  91 }
  92
  93 /*
  94  * Copy the vertex header along with its data from the current
  95  * vertex buffer into a buffer holding vertices arranged
  96  * into decomposed primitives (i.e. buffer without the
  97  * adjacency vertices)
  98  */
  99 static void
 100 copy_verts(struct draw_assembler *asmblr,
 101            unsigned *indices, unsigned num_indices)
 102 {
 103    unsigned i;
 104
 105    char *output = (char*)asmblr->output_verts->verts;
 106    const char *input = (const char*)asmblr->input_verts->verts;
 107
 108    for (i = 0; i < num_indices; ++i) {
 109       unsigned idx = indices[i];
 110       unsigned output_offset =
 111          asmblr->output_verts->count * asmblr->output_verts->stride;
 112       unsigned input_offset = asmblr->input_verts->stride * idx;
 113       memcpy(output + output_offset, input + input_offset,
 114              asmblr->input_verts->vertex_size);
 115       asmblr->output_verts->count += 1;
 116    }
 117    ++asmblr->num_prims;
 118 }
 119
 120
 121 static void
 122 inject_primid(struct draw_assembler *asmblr,
 123               unsigned idx,
 124               unsigned primid)
 125 {
 126    int slot = asmblr->primid_slot;
 127    char *input = (char*)asmblr->input_verts->verts;
 128    unsigned input_offset = asmblr->input_verts->stride * idx;
 129    struct vertex_header *v = (struct vertex_header*)(input + input_offset);
 130
 131    /* In case the backend doesn't care about it */
 132    if (slot < 0) {
 133       return;
 134    }
 135
 136    memcpy(&v->data[slot][0], &primid, sizeof(primid));
 137    memcpy(&v->data[slot][1], &primid, sizeof(primid));
 138    memcpy(&v->data[slot][2], &primid, sizeof(primid));
 139    memcpy(&v->data[slot][3], &primid, sizeof(primid));
 140 }
 141
 142
 143 static void
 144 prim_point(struct draw_assembler *asmblr,
 145            unsigned idx)
 146 {
 147    unsigned indices[1];
 148
 149    if (asmblr->needs_primid) {
 150       inject_primid(asmblr, idx, asmblr->primid++);
 151    }
 152    indices[0] = idx;
 153
 154    copy_verts(asmblr, indices, 1);
 155 }
 156
 157 static void
 158 prim_line(struct draw_assembler *asmblr,
 159           unsigned i0, unsigned i1)
 160 {
 161    unsigned indices[2];
 162
 163    if (asmblr->needs_primid) {
 164       inject_primid(asmblr, i0, asmblr->primid);
 165       inject_primid(asmblr, i1, asmblr->primid++);
 166    }
 167    indices[0] = i0;
 168    indices[1] = i1;
 169
 170    copy_verts(asmblr, indices, 2);
 171 }
 172
 173 static void
 174 prim_tri(struct draw_assembler *asmblr,
 175          unsigned i0, unsigned i1, unsigned i2)
 176 {
 177    unsigned indices[3];
 178
 179    if (asmblr->needs_primid) {
 180       inject_primid(asmblr, i0, asmblr->primid);
 181       inject_primid(asmblr, i1, asmblr->primid);
 182       inject_primid(asmblr, i2, asmblr->primid++);
 183    }
 184    indices[0] = i0;
 185    indices[1] = i1;
 186    indices[2] = i2;
 187
 188    copy_verts(asmblr, indices, 3);
 189 }
 190
 191 void
 192 draw_prim_assembler_prepare_outputs(struct draw_assembler *ia)
 193 {
 194    struct draw_context *draw = ia->draw;
 195    if (needs_primid(draw)) {
 196       ia->primid_slot = draw_alloc_extra_vertex_attrib(
 197          ia->draw, TGSI_SEMANTIC_PRIMID, 0);
 198    } else {
 199       ia->primid_slot = -1;
 200    }
 201 }
 202
 203
 204 #define FUNC assembler_run_linear
 205 #define GET_ELT(idx) (start + (idx))
 206 #include "draw_prim_assembler_tmp.h"
 207
 208 #define FUNC assembler_run_elts
 209 #define LOCAL_VARS   const ushort *elts = input_prims->elts;
 210 #define GET_ELT(idx) (elts[start + (idx)])
 211 #include "draw_prim_assembler_tmp.h"
 212
 213
 214
 215 /*
 216  * Primitive assembler breaks up adjacency primitives and assembles
 217  * the base primitives they represent, e.g. vertices forming
 218  * PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY
 219  * become vertices forming PIPE_PRIM_TRIANGLES
 220  * This is needed because specification says that the adjacency
 221  * primitives are only visible in the geometry shader so we need
 222  * to get rid of them so that the rest of the pipeline can
 223  * process the inputs.
 224  */
 225 void
 226 draw_prim_assembler_run(struct draw_context *draw,
 227                         const struct draw_prim_info *input_prims,
 228                         const struct draw_vertex_info *input_verts,
 229                         struct draw_prim_info *output_prims,
 230                         struct draw_vertex_info *output_verts)
 231 {
 232    struct draw_assembler *asmblr = draw->ia;
 233    unsigned start, i;
 234    unsigned assembled_prim = u_reduced_prim(input_prims->prim);
 235    unsigned max_primitives = u_decomposed_prims_for_vertices(
 236       input_prims->prim, input_prims->count);
 237    unsigned max_verts = u_vertices_per_prim(assembled_prim) * max_primitives;
 238
 239    asmblr->output_prims = output_prims;
 240    asmblr->output_verts = output_verts;
 241    asmblr->input_prims = input_prims;
 242    asmblr->input_verts = input_verts;
 243    asmblr->needs_primid = needs_primid(asmblr->draw);
 244    asmblr->num_prims = 0;
 245
 246    output_prims->linear = TRUE;
 247    output_prims->elts = NULL;
 248    output_prims->start = 0;
 249    output_prims->prim = assembled_prim;
 250    output_prims->flags = 0x0;
 251    output_prims->primitive_lengths = MALLOC(sizeof(unsigned));
 252    output_prims->primitive_lengths[0] = 0;
 253    output_prims->primitive_count = 1;
 254
 255    output_verts->vertex_size = input_verts->vertex_size;
 256    output_verts->stride = input_verts->stride;
 257    output_verts->verts = (struct vertex_header*)MALLOC(
 258       input_verts->vertex_size * max_verts);
 259    output_verts->count = 0;
 260
 261
 262    for (start = i = 0; i < input_prims->primitive_count;
 263         start += input_prims->primitive_lengths[i], i++)
 264    {
 265       unsigned count = input_prims->primitive_lengths[i];
 266       if (input_prims->linear) {
 267          assembler_run_linear(asmblr, input_prims, input_verts,
 268                               start, count);
 269       } else {
 270          assembler_run_elts(asmblr, input_prims, input_verts,
 271                             start, count);
 272       }
 273    }
 274
 275    output_prims->primitive_lengths[0] = output_verts->count;
 276    output_prims->count = output_verts->count;
 277 }
 278
 279 struct draw_assembler *
 280 draw_prim_assembler_create(struct draw_context *draw)
 281 {
 282    struct draw_assembler *ia = CALLOC_STRUCT( draw_assembler );
 283
 284    ia->draw = draw;
 285
 286    return ia;
 287 }
 288
 289 void
 290 draw_prim_assembler_destroy(struct draw_assembler *ia)
 291 {
 292    FREE(ia);
 293 }
 294
 295
 296 /*
 297  * Called at the very begin of the draw call with a new instance
 298  * Used to reset state that should persist between primitive restart.
 299  */
 300 void
 301 draw_prim_assembler_new_instance(struct draw_assembler *asmblr)
 302 {
 303    asmblr->primid = 0;
 304 }