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    const static unsigned values[][2] = {
  82       { 1, 0 }, /* PIPE_PRIM_POINTS */
  83       { 2, 2 }, /* PIPE_PRIM_LINES */
  84       { 2, 0 }, /* PIPE_PRIM_LINE_LOOP */
  85       { 2, 0 }, /* PIPE_PRIM_LINE_STRIP */
  86       { 3, 3 }, /* PIPE_PRIM_TRIANGLES */
  87       { 3, 0 }, /* PIPE_PRIM_TRIANGLE_STRIP */
  88       { 3, 0 }, /* PIPE_PRIM_TRIANGLE_FAN */
  89       { 4, 4 }, /* PIPE_PRIM_TRIANGLE_QUADS */
  90       { 4, 2 }, /* PIPE_PRIM_TRIANGLE_QUAD_STRIP */
  91       { 3, 0 }, /* PIPE_PRIM_TRIANGLE_POLYGON */
  92       { 4, 4 }, /* PIPE_PRIM_LINES_ADJACENCY */
  93       { 4, 0 }, /* PIPE_PRIM_LINE_STRIP_ADJACENCY */
  94       { 6, 5 }, /* PIPE_PRIM_TRIANGLES_ADJACENCY */
  95       { 4, 0 }, /* PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY */
  96    };
  97
  98    if (unlikely(pipe_prim >= PIPE_PRIM_MAX)) {
  99        *nr = 0;
 100        return FALSE;
 101    }
 102
 103    ok = (*nr >= values[pipe_prim][0]);
 104    if (values[pipe_prim][1])
 105        *nr -= (*nr % values[pipe_prim][1]);
 106
 107    if (!ok)
 108       *nr = 0;
 109
 110    return ok;
 111 }
 112
 113
 114 static INLINE unsigned u_reduced_prim( unsigned pipe_prim )
 115 {
 116    switch (pipe_prim) {
 117    case PIPE_PRIM_POINTS:
 118       return PIPE_PRIM_POINTS;
 119
 120    case PIPE_PRIM_LINES:
 121    case PIPE_PRIM_LINE_STRIP:
 122    case PIPE_PRIM_LINE_LOOP:
 123       return PIPE_PRIM_LINES;
 124
 125    default:
 126       return PIPE_PRIM_TRIANGLES;
 127    }
 128 }
 129
 130 static INLINE unsigned
 131 u_vertices_per_prim(int primitive)
 132 {
 133    switch(primitive) {
 134    case PIPE_PRIM_POINTS:
 135       return 1;
 136    case PIPE_PRIM_LINES:
 137    case PIPE_PRIM_LINE_LOOP:
 138    case PIPE_PRIM_LINE_STRIP:
 139       return 2;
 140    case PIPE_PRIM_TRIANGLES:
 141    case PIPE_PRIM_TRIANGLE_STRIP:
 142    case PIPE_PRIM_TRIANGLE_FAN:
 143       return 3;
 144    case PIPE_PRIM_LINES_ADJACENCY:
 145    case PIPE_PRIM_LINE_STRIP_ADJACENCY:
 146       return 4;
 147    case PIPE_PRIM_TRIANGLES_ADJACENCY:
 148    case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
 149       return 6;
 150
 151    /* following primitives should never be used
 152     * with geometry shaders abd their size is
 153     * undefined */
 154    case PIPE_PRIM_POLYGON:
 155    case PIPE_PRIM_QUADS:
 156    case PIPE_PRIM_QUAD_STRIP:
 157    default:
 158       debug_printf("Unrecognized geometry shader primitive");
 159       return 3;
 160    }
 161 }
 162
 163 /**
 164  * Returns the number of decomposed primitives for the given
 165  * vertex count.
 166  * Geometry shader is invoked once for each triangle in
 167  * triangle strip, triangle fans and triangles and once
 168  * for each line in line strip, line loop, lines.
 169  */
 170 static INLINE unsigned
 171 u_gs_prims_for_vertices(int primitive, int vertices)
 172 {
 173    switch(primitive) {
 174    case PIPE_PRIM_POINTS:
 175       return vertices;
 176    case PIPE_PRIM_LINES:
 177       return vertices / 2;
 178    case PIPE_PRIM_LINE_LOOP:
 179       return vertices;
 180    case PIPE_PRIM_LINE_STRIP:
 181       return vertices - 1;
 182    case PIPE_PRIM_TRIANGLES:
 183       return vertices /  3;
 184    case PIPE_PRIM_TRIANGLE_STRIP:
 185       return vertices - 2;
 186    case PIPE_PRIM_TRIANGLE_FAN:
 187       return vertices - 2;
 188    case PIPE_PRIM_LINES_ADJACENCY:
 189       return vertices / 2;
 190    case PIPE_PRIM_LINE_STRIP_ADJACENCY:
 191       return vertices - 1;
 192    case PIPE_PRIM_TRIANGLES_ADJACENCY:
 193       return vertices / 3;
 194    case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
 195       return vertices - 2;
 196
 197    /* following primitives should never be used
 198     * with geometry shaders abd their size is
 199     * undefined */
 200    case PIPE_PRIM_POLYGON:
 201    case PIPE_PRIM_QUADS:
 202    case PIPE_PRIM_QUAD_STRIP:
 203    default:
 204       debug_printf("Unrecognized geometry shader primitive");
 205       return 3;
 206    }
 207 }
 208
 209 const char *u_prim_name( unsigned pipe_prim );
 210
 211 #endif