src/mesa/vbo/vbo_exec.c

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 1999-2005  Brian Paul   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 "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included
  14  * in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22  * OTHER DEALINGS IN THE SOFTWARE.
  23  *
  24  * Authors:
  25  *    Keith Whitwell <keithw@vmware.com>
  26  */
  27
  28
  29 #include "main/glheader.h"
  30 #include "main/arrayobj.h"
  31 #include "main/api_arrayelt.h"
  32 #include "main/vtxfmt.h"
  33 #include "vbo_private.h"
  34
  35 const GLubyte
  36 _vbo_attribute_alias_map[VP_MODE_MAX][VERT_ATTRIB_MAX] = {
  37    /* VP_MODE_FF: */
  38    {
  39       VBO_ATTRIB_POS,                 /* VERT_ATTRIB_POS */
  40       VBO_ATTRIB_NORMAL,              /* VERT_ATTRIB_NORMAL */
  41       VBO_ATTRIB_COLOR0,              /* VERT_ATTRIB_COLOR0 */
  42       VBO_ATTRIB_COLOR1,              /* VERT_ATTRIB_COLOR1 */
  43       VBO_ATTRIB_FOG,                 /* VERT_ATTRIB_FOG */
  44       VBO_ATTRIB_COLOR_INDEX,         /* VERT_ATTRIB_COLOR_INDEX */
  45       VBO_ATTRIB_EDGEFLAG,            /* VERT_ATTRIB_EDGEFLAG */
  46       VBO_ATTRIB_TEX0,                /* VERT_ATTRIB_TEX0 */
  47       VBO_ATTRIB_TEX1,                /* VERT_ATTRIB_TEX1 */
  48       VBO_ATTRIB_TEX2,                /* VERT_ATTRIB_TEX2 */
  49       VBO_ATTRIB_TEX3,                /* VERT_ATTRIB_TEX3 */
  50       VBO_ATTRIB_TEX4,                /* VERT_ATTRIB_TEX4 */
  51       VBO_ATTRIB_TEX5,                /* VERT_ATTRIB_TEX5 */
  52       VBO_ATTRIB_TEX6,                /* VERT_ATTRIB_TEX6 */
  53       VBO_ATTRIB_TEX7,                /* VERT_ATTRIB_TEX7 */
  54       VBO_ATTRIB_POINT_SIZE,          /* VERT_ATTRIB_POINT_SIZE */
  55       VBO_ATTRIB_GENERIC0,            /* VERT_ATTRIB_GENERIC0 */
  56       VBO_ATTRIB_GENERIC1,            /* VERT_ATTRIB_GENERIC1 */
  57       VBO_ATTRIB_GENERIC2,            /* VERT_ATTRIB_GENERIC2 */
  58       VBO_ATTRIB_GENERIC3,            /* VERT_ATTRIB_GENERIC3 */
  59       VBO_ATTRIB_MAT_FRONT_AMBIENT,   /* VERT_ATTRIB_GENERIC4 */
  60       VBO_ATTRIB_MAT_BACK_AMBIENT,    /* VERT_ATTRIB_GENERIC5 */
  61       VBO_ATTRIB_MAT_FRONT_DIFFUSE,   /* VERT_ATTRIB_GENERIC6 */
  62       VBO_ATTRIB_MAT_BACK_DIFFUSE,    /* VERT_ATTRIB_GENERIC7 */
  63       VBO_ATTRIB_MAT_FRONT_SPECULAR,  /* VERT_ATTRIB_GENERIC8 */
  64       VBO_ATTRIB_MAT_BACK_SPECULAR,   /* VERT_ATTRIB_GENERIC9 */
  65       VBO_ATTRIB_MAT_FRONT_EMISSION,  /* VERT_ATTRIB_GENERIC10 */
  66       VBO_ATTRIB_MAT_BACK_EMISSION,   /* VERT_ATTRIB_GENERIC11 */
  67       VBO_ATTRIB_MAT_FRONT_SHININESS, /* VERT_ATTRIB_GENERIC12 */
  68       VBO_ATTRIB_MAT_BACK_SHININESS,  /* VERT_ATTRIB_GENERIC13 */
  69       VBO_ATTRIB_MAT_FRONT_INDEXES,   /* VERT_ATTRIB_GENERIC14 */
  70       VBO_ATTRIB_MAT_BACK_INDEXES     /* VERT_ATTRIB_GENERIC15 */
  71    },
  72
  73    /* VP_MODE_SHADER: */
  74    {
  75       VBO_ATTRIB_POS,                 /* VERT_ATTRIB_POS */
  76       VBO_ATTRIB_NORMAL,              /* VERT_ATTRIB_NORMAL */
  77       VBO_ATTRIB_COLOR0,              /* VERT_ATTRIB_COLOR0 */
  78       VBO_ATTRIB_COLOR1,              /* VERT_ATTRIB_COLOR1 */
  79       VBO_ATTRIB_FOG,                 /* VERT_ATTRIB_FOG */
  80       VBO_ATTRIB_COLOR_INDEX,         /* VERT_ATTRIB_COLOR_INDEX */
  81       VBO_ATTRIB_EDGEFLAG,            /* VERT_ATTRIB_EDGEFLAG */
  82       VBO_ATTRIB_TEX0,                /* VERT_ATTRIB_TEX0 */
  83       VBO_ATTRIB_TEX1,                /* VERT_ATTRIB_TEX1 */
  84       VBO_ATTRIB_TEX2,                /* VERT_ATTRIB_TEX2 */
  85       VBO_ATTRIB_TEX3,                /* VERT_ATTRIB_TEX3 */
  86       VBO_ATTRIB_TEX4,                /* VERT_ATTRIB_TEX4 */
  87       VBO_ATTRIB_TEX5,                /* VERT_ATTRIB_TEX5 */
  88       VBO_ATTRIB_TEX6,                /* VERT_ATTRIB_TEX6 */
  89       VBO_ATTRIB_TEX7,                /* VERT_ATTRIB_TEX7 */
  90       VBO_ATTRIB_POINT_SIZE,          /* VERT_ATTRIB_POINT_SIZE */
  91       VBO_ATTRIB_GENERIC0,            /* VERT_ATTRIB_GENERIC0 */
  92       VBO_ATTRIB_GENERIC1,            /* VERT_ATTRIB_GENERIC1 */
  93       VBO_ATTRIB_GENERIC2,            /* VERT_ATTRIB_GENERIC2 */
  94       VBO_ATTRIB_GENERIC3,            /* VERT_ATTRIB_GENERIC3 */
  95       VBO_ATTRIB_GENERIC4,            /* VERT_ATTRIB_GENERIC4 */
  96       VBO_ATTRIB_GENERIC5,            /* VERT_ATTRIB_GENERIC5 */
  97       VBO_ATTRIB_GENERIC6,            /* VERT_ATTRIB_GENERIC6 */
  98       VBO_ATTRIB_GENERIC7,            /* VERT_ATTRIB_GENERIC7 */
  99       VBO_ATTRIB_GENERIC8,            /* VERT_ATTRIB_GENERIC8 */
 100       VBO_ATTRIB_GENERIC9,            /* VERT_ATTRIB_GENERIC9 */
 101       VBO_ATTRIB_GENERIC10,           /* VERT_ATTRIB_GENERIC10 */
 102       VBO_ATTRIB_GENERIC11,           /* VERT_ATTRIB_GENERIC11 */
 103       VBO_ATTRIB_GENERIC12,           /* VERT_ATTRIB_GENERIC12 */
 104       VBO_ATTRIB_GENERIC13,           /* VERT_ATTRIB_GENERIC13 */
 105       VBO_ATTRIB_GENERIC14,           /* VERT_ATTRIB_GENERIC14 */
 106       VBO_ATTRIB_GENERIC15            /* VERT_ATTRIB_GENERIC15 */
 107    }
 108 };
 109
 110
 111 void
 112 vbo_exec_init(struct gl_context *ctx, bool use_buffer_objects)
 113 {
 114    struct vbo_exec_context *exec = &vbo_context(ctx)->exec;
 115
 116    exec->ctx = ctx;
 117
 118    vbo_exec_vtx_init(exec, use_buffer_objects);
 119
 120    ctx->Driver.NeedFlush = 0;
 121    ctx->Driver.CurrentExecPrimitive = PRIM_OUTSIDE_BEGIN_END;
 122
 123    exec->eval.recalculate_maps = GL_TRUE;
 124 }
 125
 126
 127 void vbo_exec_destroy( struct gl_context *ctx )
 128 {
 129    struct vbo_exec_context *exec = &vbo_context(ctx)->exec;
 130
 131    vbo_exec_vtx_destroy( exec );
 132 }
 133
 134
 135 /**
 136  * In some degenarate cases we can improve our ability to merge
 137  * consecutive primitives.  For example:
 138  * glBegin(GL_LINE_STRIP);
 139  * glVertex(1);
 140  * glVertex(1);
 141  * glEnd();
 142  * glBegin(GL_LINE_STRIP);
 143  * glVertex(1);
 144  * glVertex(1);
 145  * glEnd();
 146  * Can be merged as a GL_LINES prim with four vertices.
 147  *
 148  * This function converts 2-vertex line strips/loops into GL_LINES, etc.
 149  */
 150 void
 151 vbo_try_prim_conversion(struct _mesa_prim *p)
 152 {
 153    if (p->mode == GL_LINE_STRIP && p->count == 2) {
 154       /* convert 2-vertex line strip to a separate line */
 155       p->mode = GL_LINES;
 156    }
 157    else if ((p->mode == GL_TRIANGLE_STRIP || p->mode == GL_TRIANGLE_FAN)
 158        && p->count == 3) {
 159       /* convert 3-vertex tri strip or fan to a separate triangle */
 160       p->mode = GL_TRIANGLES;
 161    }
 162
 163    /* Note: we can't convert a 4-vertex quad strip to a separate quad
 164     * because the vertex ordering is different.  We'd have to muck
 165     * around in the vertex data to make it work.
 166     */
 167 }
 168
 169
 170 /**
 171  * Helper function for determining if two subsequent glBegin/glEnd
 172  * primitives can be combined.  This is only possible for GL_POINTS,
 173  * GL_LINES, GL_TRIANGLES and GL_QUADS.
 174  * If we return true, it means that we can concatenate p1 onto p0 (and
 175  * discard p1).
 176  */
 177 bool
 178 vbo_can_merge_prims(const struct _mesa_prim *p0, const struct _mesa_prim *p1)
 179 {
 180    if (!p0->begin ||
 181        !p1->begin ||
 182        !p0->end ||
 183        !p1->end)
 184       return false;
 185
 186    /* The prim mode must match (ex: both GL_TRIANGLES) */
 187    if (p0->mode != p1->mode)
 188       return false;
 189
 190    /* p1's vertices must come right after p0 */
 191    if (p0->start + p0->count != p1->start)
 192       return false;
 193
 194    assert(p0->basevertex == p1->basevertex);
 195
 196    /* can always merge subsequent GL_POINTS primitives */
 197    if (p0->mode == GL_POINTS)
 198       return true;
 199
 200    /* independent lines with no extra vertices */
 201    if (p0->mode == GL_LINES && p0->count % 2 == 0)
 202       return true;
 203
 204    /* independent tris */
 205    if (p0->mode == GL_TRIANGLES && p0->count % 3 == 0)
 206       return true;
 207
 208    /* independent quads */
 209    if (p0->mode == GL_QUADS && p0->count % 4 == 0)
 210       return true;
 211
 212    return false;
 213 }
 214
 215
 216 /**
 217  * If we've determined that p0 and p1 can be merged, this function
 218  * concatenates p1 onto p0.
 219  */
 220 void
 221 vbo_merge_prims(struct _mesa_prim *p0, const struct _mesa_prim *p1)
 222 {
 223    assert(vbo_can_merge_prims(p0, p1));
 224
 225    p0->count += p1->count;
 226    p0->end = p1->end;
 227 }
 228
 229 /**
 230  * Copy zero, one or two vertices from the current vertex buffer into
 231  * the temporary "copy" buffer.
 232  * This is used when a single primitive overflows a vertex buffer and
 233  * we need to continue the primitive in a new vertex buffer.
 234  * The temporary "copy" buffer holds the vertices which need to get
 235  * copied from the old buffer to the new one.
 236  */
 237 unsigned
 238 vbo_copy_vertices(struct gl_context *ctx,
 239                   GLenum mode,
 240                   struct _mesa_prim *last_prim,
 241                   unsigned vertex_size,
 242                   bool in_dlist,
 243                   fi_type *dst,
 244                   const fi_type *src)
 245 {
 246    const unsigned count = last_prim->count;
 247    unsigned copy = 0;
 248
 249    switch (mode) {
 250    case GL_POINTS:
 251       return 0;
 252    case GL_LINES:
 253       copy = count % 2;
 254       break;
 255    case GL_TRIANGLES:
 256       copy = count % 3;
 257       break;
 258    case GL_QUADS:
 259    case GL_LINES_ADJACENCY:
 260       copy = count % 4;
 261       break;
 262    case GL_TRIANGLES_ADJACENCY:
 263       copy = count % 6;
 264       break;
 265    case GL_LINE_STRIP:
 266       copy = MIN2(1, count);
 267       break;
 268    case GL_LINE_STRIP_ADJACENCY:
 269       /* We need to copy 3 vertices, because:
 270        *    Last strip:  ---o---o---x     (last line)
 271        *    Next strip:     x---o---o---  (next line)
 272        */
 273       copy = MIN2(3, count);
 274       break;
 275    case GL_PATCHES:
 276       if (in_dlist) {
 277          /* We don't know the value of GL_PATCH_VERTICES when compiling
 278           * a display list.
 279           *
 280           * Fail an assertion in debug builds and use the value of 3
 281           * in release builds, which is more likely than any other value.
 282           */
 283          assert(!"patch_vertices is unknown");
 284          copy = count % 3;
 285       } else {
 286          copy = count % ctx->TessCtrlProgram.patch_vertices;
 287       }
 288       break;
 289    case GL_LINE_LOOP:
 290       if (!in_dlist && last_prim->begin == 0) {
 291          /* We're dealing with the second or later section of a split/wrapped
 292           * GL_LINE_LOOP.  Since we're converting line loops to line strips,
 293           * we've already incremented the last_prim->start counter by one to
 294           * skip the 0th vertex in the loop.  We need to undo that (effectively
 295           * subtract one from last_prim->start) so that we copy the 0th vertex
 296           * to the next vertex buffer.
 297           */
 298          assert(last_prim->start > 0);
 299          src -= vertex_size;
 300       }
 301       /* fall-through */
 302    case GL_TRIANGLE_FAN:
 303    case GL_POLYGON:
 304       if (count == 0) {
 305          return 0;
 306       } else if (count == 1) {
 307          memcpy(dst, src + 0, vertex_size * sizeof(GLfloat));
 308          return 1;
 309       } else {
 310          memcpy(dst, src + 0, vertex_size * sizeof(GLfloat));
 311          memcpy(dst + vertex_size, src + (count - 1) * vertex_size,
 312                 vertex_size * sizeof(GLfloat));
 313          return 2;
 314       }
 315    case GL_TRIANGLE_STRIP:
 316       /* Draw an even number of triangles to keep front/back facing the same. */
 317       last_prim->count -= count % 2;
 318       /* fallthrough */
 319    case GL_QUAD_STRIP:
 320       if (count <= 1)
 321          copy = count;
 322       else
 323          copy = 2 + (count % 2);
 324       break;
 325    case PRIM_OUTSIDE_BEGIN_END:
 326       return 0;
 327    case GL_TRIANGLE_STRIP_ADJACENCY:
 328       /* TODO: Splitting tri strips with adjacency is too complicated. */
 329    default:
 330       unreachable("Unexpected primitive type");
 331       return 0;
 332    }
 333
 334    memcpy(dst, src + (count - copy) * vertex_size,
 335           copy * vertex_size * sizeof(GLfloat));
 336    return copy;
 337 }