1/*
2 * Copyright 2009 VMware, Inc.
3 * All Rights Reserved.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * on the rights to use, copy, modify, merge, publish, distribute, sub
9 * license, and/or sell copies of the Software, and to permit persons to whom
10 * the Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the next
13 * paragraph) shall be included in all copies or substantial portions of the
14 * Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.  IN NO EVENT SHALL
19 * VMWARE AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
20 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
21 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
22 * USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25#ifndef U_INDICES_H
26#define U_INDICES_H
27
28#include "pipe/p_compiler.h"
29#include "pipe/p_defines.h"
30
31/* First/last provoking vertex */
32#define PV_FIRST      0
33#define PV_LAST       1
34#define PV_COUNT      2
35
36/* primitive restart disable/enable flags */
37#define PR_DISABLE 0
38#define PR_ENABLE 1
39#define PR_COUNT 2
40
41
42/**
43 * Index translator function (for glDrawElements() case)
44 *
45 * \param in     the input index buffer
46 * \param start  the index of the first vertex (pipe_draw_info::start)
47 * \param nr     the number of vertices (pipe_draw_info::count)
48 * \param out    output buffer big enough for nr vertices (of
49 *    @out_index_size bytes each)
50 */
51typedef void (*u_translate_func)( const void *in,
52                                  unsigned start,
53                                  unsigned in_nr,
54                                  unsigned out_nr,
55                                  unsigned restart_index,
56                                  void *out );
57
58/**
59 * Index generator function (for glDrawArrays() case)
60 *
61 * \param start  the index of the first vertex (pipe_draw_info::start)
62 * \param nr     the number of vertices (pipe_draw_info::count)
63 * \param out    output buffer big enough for nr vertices (of
64 *    @out_index_size bytes each)
65 */
66typedef void (*u_generate_func)( unsigned start,
67                                 unsigned nr,
68                                 void *out );
69
70
71/* Return codes describe the translate/generate operation.  Caller may
72 * be able to reuse translated indices under some circumstances.
73 */
74enum indices_mode {
75   U_TRANSLATE_ERROR = -1,
76   U_TRANSLATE_NORMAL = 1,
77   U_TRANSLATE_MEMCPY = 2,
78   U_GENERATE_LINEAR  = 3,
79   U_GENERATE_REUSABLE= 4,
80   U_GENERATE_ONE_OFF = 5,
81};
82
83void u_index_init( void );
84
85/* returns the primitive type resulting from index translation */
86enum pipe_prim_type
87u_index_prim_type_convert(unsigned hw_mask, enum pipe_prim_type prim, bool pv_matches);
88
89static inline unsigned
90u_index_size_convert(unsigned index_size)
91{
92   return (index_size == 4) ? 4 : 2;
93}
94
95unsigned
96u_index_count_converted_indices(unsigned hw_mask, bool pv_matches, enum pipe_prim_type prim, unsigned nr);
97
98/**
99 * For indexed drawing, this function determines what kind of primitive
100 * transformation is needed (if any) for handling:
101 * - unsupported primitive types (such as PIPE_PRIM_POLYGON)
102 * - changing the provoking vertex
103 * - primitive restart
104 * - index size (1 byte, 2 byte or 4 byte indexes)
105 */
106enum indices_mode
107u_index_translator(unsigned hw_mask,
108                   enum pipe_prim_type prim,
109                   unsigned in_index_size,
110                   unsigned nr,
111                   unsigned in_pv,   /* API */
112                   unsigned out_pv,  /* hardware */
113                   unsigned prim_restart,
114                   enum pipe_prim_type *out_prim,
115                   unsigned *out_index_size,
116                   unsigned *out_nr,
117                   u_translate_func *out_translate);
118
119
120/**
121 * For non-indexed drawing, this function determines what kind of primitive
122 * transformation is needed (see above).
123 *
124 * Note that even when generating it is necessary to know what the
125 * API's PV is, as the indices generated will depend on whether it is
126 * the same as hardware or not, and in the case of triangle strips,
127 * whether it is first or last.
128 */
129enum indices_mode
130u_index_generator(unsigned hw_mask,
131                  enum pipe_prim_type prim,
132                  unsigned start,
133                  unsigned nr,
134                  unsigned in_pv,   /* API */
135                  unsigned out_pv,  /* hardware */
136                  enum pipe_prim_type *out_prim,
137                  unsigned *out_index_size,
138                  unsigned *out_nr,
139                  u_generate_func *out_generate);
140
141
142void u_unfilled_init( void );
143
144/**
145 * If the driver can't handle "unfilled" primitives (i.e. drawing triangle
146 * primitives as 3 lines or 3 points) this function can be used to translate
147 * an indexed primitive into a new indexed primitive to draw as lines or
148 * points.
149 */
150enum indices_mode
151u_unfilled_translator(enum pipe_prim_type prim,
152                      unsigned in_index_size,
153                      unsigned nr,
154                      unsigned unfilled_mode,
155                      enum pipe_prim_type *out_prim,
156                      unsigned *out_index_size,
157                      unsigned *out_nr,
158                      u_translate_func *out_translate);
159
160/**
161 * As above, but for non-indexed (array) primitives.
162 */
163enum indices_mode
164u_unfilled_generator(enum pipe_prim_type prim,
165                     unsigned start,
166                     unsigned nr,
167                     unsigned unfilled_mode,
168                     enum pipe_prim_type *out_prim,
169                     unsigned *out_index_size,
170                     unsigned *out_nr,
171                     u_generate_func *out_generate);
172
173#endif
174