src/gallium/auxiliary/util/u_prim.h

   1 /**************************************************************************
   2  *
   3  * Copyright 2008 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 #ifndef U_BLIT_H
  30 #define U_BLIT_H
  31
  32
  33 #include "pipe/p_defines.h"
  34 #include "util/u_debug.h"
  35
  36 #ifdef __cplusplus
  37 extern "C" {
  38 #endif
  39
  40 static INLINE boolean u_validate_pipe_prim( unsigned pipe_prim, unsigned nr )
  41 {
  42    boolean ok = TRUE;
  43
  44    switch (pipe_prim) {
  45    case PIPE_PRIM_POINTS:
  46       ok = (nr >= 1);
  47       break;
  48    case PIPE_PRIM_LINES:
  49       ok = (nr >= 2);
  50       break;
  51    case PIPE_PRIM_LINE_STRIP:
  52    case PIPE_PRIM_LINE_LOOP:
  53       ok = (nr >= 2);
  54       break;
  55    case PIPE_PRIM_TRIANGLES:
  56       ok = (nr >= 3);
  57       break;
  58    case PIPE_PRIM_TRIANGLE_STRIP:
  59    case PIPE_PRIM_TRIANGLE_FAN:
  60    case PIPE_PRIM_POLYGON:
  61       ok = (nr >= 3);
  62       break;
  63    case PIPE_PRIM_QUADS:
  64       ok = (nr >= 4);
  65       break;
  66    case PIPE_PRIM_QUAD_STRIP:
  67       ok = (nr >= 4);
  68       break;
  69    default:
  70       ok = 0;
  71       break;
  72    }
  73
  74    return ok;
  75 }
  76
  77
  78 static INLINE boolean u_trim_pipe_prim( unsigned pipe_prim, unsigned *nr )
  79 {
  80    boolean ok = TRUE;
  81
  82    switch (pipe_prim) {
  83    case PIPE_PRIM_POINTS:
  84       ok = (*nr >= 1);
  85       break;
  86    case PIPE_PRIM_LINES:
  87       ok = (*nr >= 2);
  88       *nr -= (*nr % 2);
  89       break;
  90    case PIPE_PRIM_LINE_STRIP:
  91    case PIPE_PRIM_LINE_LOOP:
  92       ok = (*nr >= 2);
  93       break;
  94    case PIPE_PRIM_TRIANGLES:
  95       ok = (*nr >= 3);
  96       *nr -= (*nr % 3);
  97       break;
  98    case PIPE_PRIM_TRIANGLE_STRIP:
  99    case PIPE_PRIM_TRIANGLE_FAN:
 100    case PIPE_PRIM_POLYGON:
 101       ok = (*nr >= 3);
 102       break;
 103    case PIPE_PRIM_QUADS:
 104       ok = (*nr >= 4);
 105       *nr -= (*nr % 4);
 106       break;
 107    case PIPE_PRIM_QUAD_STRIP:
 108       ok = (*nr >= 4);
 109       *nr -= (*nr % 2);
 110       break;
 111    case PIPE_PRIM_LINES_ADJACENCY:
 112       ok = (*nr >= 4);
 113       *nr -= (*nr % 4);
 114       break;
 115    case PIPE_PRIM_LINE_STRIP_ADJACENCY:
 116       ok = (*nr >= 4);
 117       break;
 118    case PIPE_PRIM_TRIANGLES_ADJACENCY:
 119       ok = (*nr >= 6);
 120       *nr -= (*nr % 5);
 121       break;
 122    case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
 123       ok = (*nr >= 4);
 124       break;
 125    default:
 126       ok = 0;
 127       break;
 128    }
 129
 130    if (!ok)
 131       *nr = 0;
 132
 133    return ok;
 134 }
 135
 136
 137 static INLINE unsigned u_reduced_prim( unsigned pipe_prim )
 138 {
 139    switch (pipe_prim) {
 140    case PIPE_PRIM_POINTS:
 141       return PIPE_PRIM_POINTS;
 142
 143    case PIPE_PRIM_LINES:
 144    case PIPE_PRIM_LINE_STRIP:
 145    case PIPE_PRIM_LINE_LOOP:
 146       return PIPE_PRIM_LINES;
 147
 148    default:
 149       return PIPE_PRIM_TRIANGLES;
 150    }
 151 }
 152
 153 static INLINE unsigned
 154 u_vertices_per_prim(int primitive)
 155 {
 156    switch(primitive) {
 157    case PIPE_PRIM_POINTS:
 158       return 1;
 159    case PIPE_PRIM_LINES:
 160    case PIPE_PRIM_LINE_LOOP:
 161    case PIPE_PRIM_LINE_STRIP:
 162       return 2;
 163    case PIPE_PRIM_TRIANGLES:
 164    case PIPE_PRIM_TRIANGLE_STRIP:
 165    case PIPE_PRIM_TRIANGLE_FAN:
 166       return 3;
 167    case PIPE_PRIM_LINES_ADJACENCY:
 168    case PIPE_PRIM_LINE_STRIP_ADJACENCY:
 169       return 4;
 170    case PIPE_PRIM_TRIANGLES_ADJACENCY:
 171    case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
 172       return 6;
 173
 174    /* following primitives should never be used
 175     * with geometry shaders abd their size is
 176     * undefined */
 177    case PIPE_PRIM_POLYGON:
 178    case PIPE_PRIM_QUADS:
 179    case PIPE_PRIM_QUAD_STRIP:
 180    default:
 181       debug_printf("Unrecognized geometry shader primitive");
 182       return 3;
 183    }
 184 }
 185
 186 /**
 187  * Returns the number of decomposed primitives for the given
 188  * vertex count.
 189  * Geometry shader is invoked once for each triangle in
 190  * triangle strip, triangle fans and triangles and once
 191  * for each line in line strip, line loop, lines.
 192  */
 193 static INLINE unsigned
 194 u_gs_prims_for_vertices(int primitive, int vertices)
 195 {
 196    switch(primitive) {
 197    case PIPE_PRIM_POINTS:
 198       return vertices;
 199    case PIPE_PRIM_LINES:
 200       return vertices / 2;
 201    case PIPE_PRIM_LINE_LOOP:
 202       return vertices;
 203    case PIPE_PRIM_LINE_STRIP:
 204       return vertices - 1;
 205    case PIPE_PRIM_TRIANGLES:
 206       return vertices /  3;
 207    case PIPE_PRIM_TRIANGLE_STRIP:
 208       return vertices - 2;
 209    case PIPE_PRIM_TRIANGLE_FAN:
 210       return vertices - 2;
 211    case PIPE_PRIM_LINES_ADJACENCY:
 212       return vertices / 2;
 213    case PIPE_PRIM_LINE_STRIP_ADJACENCY:
 214       return vertices - 1;
 215    case PIPE_PRIM_TRIANGLES_ADJACENCY:
 216       return vertices / 3;
 217    case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
 218       return vertices - 2;
 219
 220    /* following primitives should never be used
 221     * with geometry shaders abd their size is
 222     * undefined */
 223    case PIPE_PRIM_POLYGON:
 224    case PIPE_PRIM_QUADS:
 225    case PIPE_PRIM_QUAD_STRIP:
 226    default:
 227       debug_printf("Unrecognized geometry shader primitive");
 228       return 3;
 229    }
 230 }
 231
 232 const char *u_prim_name( unsigned pipe_prim );
 233
 234 #endif