/**************************************************************************
*
* Copyright 2008 VMware, Inc.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
* IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
#ifndef U_PRIM_H
#define U_PRIM_H
#include "pipe/p_defines.h"
#include "util/u_debug.h"
#ifdef __cplusplus
extern "C" {
#endif
struct u_prim_vertex_count {
unsigned min;
unsigned incr;
};
/**
* Decompose a primitive that is a loop, a strip, or a fan. Return the
* original primitive if it is already decomposed.
*/
static inline enum pipe_prim_type
u_decomposed_prim(enum pipe_prim_type prim)
{
switch (prim) {
case PIPE_PRIM_LINE_LOOP:
case PIPE_PRIM_LINE_STRIP:
return PIPE_PRIM_LINES;
case PIPE_PRIM_TRIANGLE_STRIP:
case PIPE_PRIM_TRIANGLE_FAN:
return PIPE_PRIM_TRIANGLES;
case PIPE_PRIM_QUAD_STRIP:
return PIPE_PRIM_QUADS;
case PIPE_PRIM_LINE_STRIP_ADJACENCY:
return PIPE_PRIM_LINES_ADJACENCY;
case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
return PIPE_PRIM_TRIANGLES_ADJACENCY;
default:
return prim;
}
}
/**
* Reduce a primitive to one of PIPE_PRIM_POINTS, PIPE_PRIM_LINES, and
* PIPE_PRIM_TRIANGLES.
*/
static inline enum pipe_prim_type
u_reduced_prim(enum pipe_prim_type prim)
{
switch (prim) {
case PIPE_PRIM_POINTS:
return PIPE_PRIM_POINTS;
case PIPE_PRIM_LINES:
case PIPE_PRIM_LINE_LOOP:
case PIPE_PRIM_LINE_STRIP:
case PIPE_PRIM_LINES_ADJACENCY:
case PIPE_PRIM_LINE_STRIP_ADJACENCY:
return PIPE_PRIM_LINES;
default:
return PIPE_PRIM_TRIANGLES;
}
}
/**
* Re-assemble a primitive to remove its adjacency.
*/
static inline enum pipe_prim_type
u_assembled_prim(enum pipe_prim_type prim)
{
switch (prim) {
case PIPE_PRIM_LINES_ADJACENCY:
case PIPE_PRIM_LINE_STRIP_ADJACENCY:
return PIPE_PRIM_LINES;
case PIPE_PRIM_TRIANGLES_ADJACENCY:
case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
return PIPE_PRIM_TRIANGLES;
default:
return prim;
}
}
/**
* Return the vertex count information for a primitive.
*
* Note that if this function is called directly or indirectly anywhere in a
* source file, it will increase the size of the binary slightly more than
* expected because of the use of a table.
*/
static inline const struct u_prim_vertex_count *
u_prim_vertex_count(enum pipe_prim_type prim)
{
static const struct u_prim_vertex_count prim_table[PIPE_PRIM_MAX] = {
{ 1, 1 }, /* PIPE_PRIM_POINTS */
{ 2, 2 }, /* PIPE_PRIM_LINES */
{ 2, 1 }, /* PIPE_PRIM_LINE_LOOP */
{ 2, 1 }, /* PIPE_PRIM_LINE_STRIP */
{ 3, 3 }, /* PIPE_PRIM_TRIANGLES */
{ 3, 1 }, /* PIPE_PRIM_TRIANGLE_STRIP */
{ 3, 1 }, /* PIPE_PRIM_TRIANGLE_FAN */
{ 4, 4 }, /* PIPE_PRIM_QUADS */
{ 4, 2 }, /* PIPE_PRIM_QUAD_STRIP */
{ 3, 1 }, /* PIPE_PRIM_POLYGON */
{ 4, 4 }, /* PIPE_PRIM_LINES_ADJACENCY */
{ 4, 1 }, /* PIPE_PRIM_LINE_STRIP_ADJACENCY */
{ 6, 6 }, /* PIPE_PRIM_TRIANGLES_ADJACENCY */
{ 6, 2 }, /* PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY */
};
return (likely(prim < PIPE_PRIM_MAX)) ? &prim_table[prim] : NULL;
}
/**
* Given a vertex count, return the number of primitives.
* For polygons, return the number of triangles.
*/
static inline unsigned
u_prims_for_vertices(enum pipe_prim_type prim, unsigned num)
{
const struct u_prim_vertex_count *info = u_prim_vertex_count(prim);
assert(info);
assert(info->incr != 0);
if (num < info->min)
return 0;
return 1 + ((num - info->min) / info->incr);
}
static inline boolean
u_validate_pipe_prim(enum pipe_prim_type pipe_prim, unsigned nr)
{
const struct u_prim_vertex_count *count = u_prim_vertex_count(pipe_prim);
return (count && nr >= count->min);
}
static inline boolean
u_trim_pipe_prim(enum pipe_prim_type pipe_prim, unsigned *nr)
{
const struct u_prim_vertex_count *count = u_prim_vertex_count(pipe_prim);
if (count && *nr >= count->min) {
if (count->incr > 1)
*nr -= (*nr % count->incr);
return TRUE;
}
else {
*nr = 0;
return FALSE;
}
}
static inline unsigned
u_vertices_per_prim(enum pipe_prim_type primitive)
{
switch(primitive) {
case PIPE_PRIM_POINTS:
return 1;
case PIPE_PRIM_LINES:
case PIPE_PRIM_LINE_LOOP:
case PIPE_PRIM_LINE_STRIP:
return 2;
case PIPE_PRIM_TRIANGLES:
case PIPE_PRIM_TRIANGLE_STRIP:
case PIPE_PRIM_TRIANGLE_FAN:
return 3;
case PIPE_PRIM_LINES_ADJACENCY:
case PIPE_PRIM_LINE_STRIP_ADJACENCY:
return 4;
case PIPE_PRIM_TRIANGLES_ADJACENCY:
case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
return 6;
/* following primitives should never be used
* with geometry shaders abd their size is
* undefined */
case PIPE_PRIM_POLYGON:
case PIPE_PRIM_QUADS:
case PIPE_PRIM_QUAD_STRIP:
default:
debug_printf("Unrecognized geometry shader primitive");
return 3;
}
}
/**
* Returns the number of decomposed primitives for the given
* vertex count.
* Parts of the pipline are invoked once for each triangle in
* triangle strip, triangle fans and triangles and once
* for each line in line strip, line loop, lines. Also
* statistics depend on knowing the exact number of decomposed
* primitives for a set of vertices.
*/
static inline unsigned
u_decomposed_prims_for_vertices(enum pipe_prim_type primitive, int vertices)
{
switch (primitive) {
case PIPE_PRIM_POINTS:
return vertices;
case PIPE_PRIM_LINES:
return vertices / 2;
case PIPE_PRIM_LINE_LOOP:
return (vertices >= 2) ? vertices : 0;
case PIPE_PRIM_LINE_STRIP:
return (vertices >= 2) ? vertices - 1 : 0;
case PIPE_PRIM_TRIANGLES:
return vertices / 3;
case PIPE_PRIM_TRIANGLE_STRIP:
return (vertices >= 3) ? vertices - 2 : 0;
case PIPE_PRIM_TRIANGLE_FAN:
return (vertices >= 3) ? vertices - 2 : 0;
case PIPE_PRIM_LINES_ADJACENCY:
return vertices / 4;
case PIPE_PRIM_LINE_STRIP_ADJACENCY:
return (vertices >= 4) ? vertices - 3 : 0;
case PIPE_PRIM_TRIANGLES_ADJACENCY:
return vertices / 6;
case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
return (vertices >= 6) ? 1 + (vertices - 6) / 2 : 0;
case PIPE_PRIM_QUADS:
return vertices / 4;
case PIPE_PRIM_QUAD_STRIP:
return (vertices >= 4) ? (vertices - 2) / 2 : 0;
/* Polygons can't be decomposed
* because the number of their vertices isn't known so
* for them and whatever else we don't recognize just
* return 1 if the number of vertices is greater than
* or equal to 3 and zero otherwise */
case PIPE_PRIM_POLYGON:
default:
debug_printf("Invalid decomposition primitive!\n");
return (vertices >= 3) ? 1 : 0;
}
}
/**
* Returns the number of reduced/tessellated primitives for the given vertex
* count. Each quad is treated as two triangles. Polygons are treated as
* triangle fans.
*/
static inline unsigned
u_reduced_prims_for_vertices(enum pipe_prim_type primitive, int vertices)
{
switch (primitive) {
case PIPE_PRIM_QUADS:
case PIPE_PRIM_QUAD_STRIP:
return u_decomposed_prims_for_vertices(primitive, vertices) * 2;
case PIPE_PRIM_POLYGON:
primitive = PIPE_PRIM_TRIANGLE_FAN;
/* fall through */
default:
return u_decomposed_prims_for_vertices(primitive, vertices);
}
}
const char *u_prim_name(enum pipe_prim_type pipe_prim);
#ifdef __cplusplus
}
#endif
#endif