1 /**************************************************************************
2 *
3 * Copyright 2008 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
29 #ifndef U_PRIM_H
30 #define U_PRIM_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 struct u_prim_vertex_count {
41 unsigned min;
42 unsigned incr;
43 };
44
45 /**
46 * Decompose a primitive that is a loop, a strip, or a fan. Return the
47 * original primitive if it is already decomposed.
48 */
49 static inline unsigned
u_decomposed_prim(unsigned prim)50 u_decomposed_prim(unsigned prim)
51 {
52 switch (prim) {
53 case PIPE_PRIM_LINE_LOOP:
54 case PIPE_PRIM_LINE_STRIP:
55 return PIPE_PRIM_LINES;
56 case PIPE_PRIM_TRIANGLE_STRIP:
57 case PIPE_PRIM_TRIANGLE_FAN:
58 return PIPE_PRIM_TRIANGLES;
59 case PIPE_PRIM_QUAD_STRIP:
60 return PIPE_PRIM_QUADS;
61 case PIPE_PRIM_LINE_STRIP_ADJACENCY:
62 return PIPE_PRIM_LINES_ADJACENCY;
63 case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
64 return PIPE_PRIM_TRIANGLES_ADJACENCY;
65 default:
66 return prim;
67 }
68 }
69
70 /**
71 * Reduce a primitive to one of PIPE_PRIM_POINTS, PIPE_PRIM_LINES, and
72 * PIPE_PRIM_TRIANGLES.
73 */
74 static inline unsigned
u_reduced_prim(unsigned prim)75 u_reduced_prim(unsigned prim)
76 {
77 switch (prim) {
78 case PIPE_PRIM_POINTS:
79 return PIPE_PRIM_POINTS;
80 case PIPE_PRIM_LINES:
81 case PIPE_PRIM_LINE_LOOP:
82 case PIPE_PRIM_LINE_STRIP:
83 case PIPE_PRIM_LINES_ADJACENCY:
84 case PIPE_PRIM_LINE_STRIP_ADJACENCY:
85 return PIPE_PRIM_LINES;
86 default:
87 return PIPE_PRIM_TRIANGLES;
88 }
89 }
90
91 /**
92 * Re-assemble a primitive to remove its adjacency.
93 */
94 static inline unsigned
u_assembled_prim(unsigned prim)95 u_assembled_prim(unsigned prim)
96 {
97 switch (prim) {
98 case PIPE_PRIM_LINES_ADJACENCY:
99 case PIPE_PRIM_LINE_STRIP_ADJACENCY:
100 return PIPE_PRIM_LINES;
101 case PIPE_PRIM_TRIANGLES_ADJACENCY:
102 case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
103 return PIPE_PRIM_TRIANGLES;
104 default:
105 return prim;
106 }
107 }
108
109 /**
110 * Return the vertex count information for a primitive.
111 *
112 * Note that if this function is called directly or indirectly anywhere in a
113 * source file, it will increase the size of the binary slightly more than
114 * expected because of the use of a table.
115 */
116 static inline const struct u_prim_vertex_count *
u_prim_vertex_count(unsigned prim)117 u_prim_vertex_count(unsigned prim)
118 {
119 static const struct u_prim_vertex_count prim_table[PIPE_PRIM_MAX] = {
120 { 1, 1 }, /* PIPE_PRIM_POINTS */
121 { 2, 2 }, /* PIPE_PRIM_LINES */
122 { 2, 1 }, /* PIPE_PRIM_LINE_LOOP */
123 { 2, 1 }, /* PIPE_PRIM_LINE_STRIP */
124 { 3, 3 }, /* PIPE_PRIM_TRIANGLES */
125 { 3, 1 }, /* PIPE_PRIM_TRIANGLE_STRIP */
126 { 3, 1 }, /* PIPE_PRIM_TRIANGLE_FAN */
127 { 4, 4 }, /* PIPE_PRIM_QUADS */
128 { 4, 2 }, /* PIPE_PRIM_QUAD_STRIP */
129 { 3, 1 }, /* PIPE_PRIM_POLYGON */
130 { 4, 4 }, /* PIPE_PRIM_LINES_ADJACENCY */
131 { 4, 1 }, /* PIPE_PRIM_LINE_STRIP_ADJACENCY */
132 { 6, 6 }, /* PIPE_PRIM_TRIANGLES_ADJACENCY */
133 { 6, 2 }, /* PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY */
134 };
135
136 return (likely(prim < PIPE_PRIM_MAX)) ? &prim_table[prim] : NULL;
137 }
138
u_validate_pipe_prim(unsigned pipe_prim,unsigned nr)139 static inline boolean u_validate_pipe_prim( unsigned pipe_prim, unsigned nr )
140 {
141 const struct u_prim_vertex_count *count = u_prim_vertex_count(pipe_prim);
142
143 return (count && nr >= count->min);
144 }
145
146
u_trim_pipe_prim(unsigned pipe_prim,unsigned * nr)147 static inline boolean u_trim_pipe_prim( unsigned pipe_prim, unsigned *nr )
148 {
149 const struct u_prim_vertex_count *count = u_prim_vertex_count(pipe_prim);
150
151 if (count && *nr >= count->min) {
152 if (count->incr > 1)
153 *nr -= (*nr % count->incr);
154 return TRUE;
155 }
156 else {
157 *nr = 0;
158 return FALSE;
159 }
160 }
161
162 static inline unsigned
u_vertices_per_prim(int primitive)163 u_vertices_per_prim(int primitive)
164 {
165 switch(primitive) {
166 case PIPE_PRIM_POINTS:
167 return 1;
168 case PIPE_PRIM_LINES:
169 case PIPE_PRIM_LINE_LOOP:
170 case PIPE_PRIM_LINE_STRIP:
171 return 2;
172 case PIPE_PRIM_TRIANGLES:
173 case PIPE_PRIM_TRIANGLE_STRIP:
174 case PIPE_PRIM_TRIANGLE_FAN:
175 return 3;
176 case PIPE_PRIM_LINES_ADJACENCY:
177 case PIPE_PRIM_LINE_STRIP_ADJACENCY:
178 return 4;
179 case PIPE_PRIM_TRIANGLES_ADJACENCY:
180 case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
181 return 6;
182
183 /* following primitives should never be used
184 * with geometry shaders abd their size is
185 * undefined */
186 case PIPE_PRIM_POLYGON:
187 case PIPE_PRIM_QUADS:
188 case PIPE_PRIM_QUAD_STRIP:
189 default:
190 debug_printf("Unrecognized geometry shader primitive");
191 return 3;
192 }
193 }
194
195 /**
196 * Returns the number of decomposed primitives for the given
197 * vertex count.
198 * Parts of the pipline are invoked once for each triangle in
199 * triangle strip, triangle fans and triangles and once
200 * for each line in line strip, line loop, lines. Also
201 * statistics depend on knowing the exact number of decomposed
202 * primitives for a set of vertices.
203 */
204 static inline unsigned
u_decomposed_prims_for_vertices(int primitive,int vertices)205 u_decomposed_prims_for_vertices(int primitive, int vertices)
206 {
207 switch (primitive) {
208 case PIPE_PRIM_POINTS:
209 return vertices;
210 case PIPE_PRIM_LINES:
211 return vertices / 2;
212 case PIPE_PRIM_LINE_LOOP:
213 return (vertices >= 2) ? vertices : 0;
214 case PIPE_PRIM_LINE_STRIP:
215 return (vertices >= 2) ? vertices - 1 : 0;
216 case PIPE_PRIM_TRIANGLES:
217 return vertices / 3;
218 case PIPE_PRIM_TRIANGLE_STRIP:
219 return (vertices >= 3) ? vertices - 2 : 0;
220 case PIPE_PRIM_TRIANGLE_FAN:
221 return (vertices >= 3) ? vertices - 2 : 0;
222 case PIPE_PRIM_LINES_ADJACENCY:
223 return vertices / 4;
224 case PIPE_PRIM_LINE_STRIP_ADJACENCY:
225 return (vertices >= 4) ? vertices - 3 : 0;
226 case PIPE_PRIM_TRIANGLES_ADJACENCY:
227 return vertices / 6;
228 case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
229 return (vertices >= 6) ? 1 + (vertices - 6) / 2 : 0;
230 case PIPE_PRIM_QUADS:
231 return vertices / 4;
232 case PIPE_PRIM_QUAD_STRIP:
233 return (vertices >= 4) ? (vertices - 2) / 2 : 0;
234 /* Polygons can't be decomposed
235 * because the number of their vertices isn't known so
236 * for them and whatever else we don't recognize just
237 * return 1 if the number of vertices is greater than
238 * or equal to 3 and zero otherwise */
239 case PIPE_PRIM_POLYGON:
240 default:
241 debug_printf("Invalid decomposition primitive!\n");
242 return (vertices >= 3) ? 1 : 0;
243 }
244 }
245
246 /**
247 * Returns the number of reduced/tessellated primitives for the given vertex
248 * count. Each quad is treated as two triangles. Polygons are treated as
249 * triangle fans.
250 */
251 static inline unsigned
u_reduced_prims_for_vertices(int primitive,int vertices)252 u_reduced_prims_for_vertices(int primitive, int vertices)
253 {
254 switch (primitive) {
255 case PIPE_PRIM_QUADS:
256 case PIPE_PRIM_QUAD_STRIP:
257 return u_decomposed_prims_for_vertices(primitive, vertices) * 2;
258 case PIPE_PRIM_POLYGON:
259 primitive = PIPE_PRIM_TRIANGLE_FAN;
260 /* fall through */
261 default:
262 return u_decomposed_prims_for_vertices(primitive, vertices);
263 }
264 }
265
266 const char *u_prim_name( unsigned pipe_prim );
267
268 #endif
269