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
86/**
87 * For indexed drawing, this function determines what kind of primitive
88 * transformation is needed (if any) for handling:
89 * - unsupported primitive types (such as PIPE_PRIM_POLYGON)
90 * - changing the provoking vertex
91 * - primitive restart
92 * - index size (1 byte, 2 byte or 4 byte indexes)
93 */
94enum indices_mode
95u_index_translator(unsigned hw_mask,
96                   enum pipe_prim_type prim,
97                   unsigned in_index_size,
98                   unsigned nr,
99                   unsigned in_pv,   /* API */
100                   unsigned out_pv,  /* hardware */
101                   unsigned prim_restart,
102                   enum pipe_prim_type *out_prim,
103                   unsigned *out_index_size,
104                   unsigned *out_nr,
105                   u_translate_func *out_translate);
106
107
108/**
109 * For non-indexed drawing, this function determines what kind of primitive
110 * transformation is needed (see above).
111 *
112 * Note that even when generating it is necessary to know what the
113 * API's PV is, as the indices generated will depend on whether it is
114 * the same as hardware or not, and in the case of triangle strips,
115 * whether it is first or last.
116 */
117enum indices_mode
118u_index_generator(unsigned hw_mask,
119                  enum pipe_prim_type prim,
120                  unsigned start,
121                  unsigned nr,
122                  unsigned in_pv,   /* API */
123                  unsigned out_pv,  /* hardware */
124                  enum pipe_prim_type *out_prim,
125                  unsigned *out_index_size,
126                  unsigned *out_nr,
127                  u_generate_func *out_generate);
128
129
130void u_unfilled_init( void );
131
132/**
133 * If the driver can't handle "unfilled" primitives (i.e. drawing triangle
134 * primitives as 3 lines or 3 points) this function can be used to translate
135 * an indexed primitive into a new indexed primitive to draw as lines or
136 * points.
137 */
138enum indices_mode
139u_unfilled_translator(enum pipe_prim_type prim,
140                      unsigned in_index_size,
141                      unsigned nr,
142                      unsigned unfilled_mode,
143                      enum pipe_prim_type *out_prim,
144                      unsigned *out_index_size,
145                      unsigned *out_nr,
146                      u_translate_func *out_translate);
147
148/**
149 * As above, but for non-indexed (array) primitives.
150 */
151enum indices_mode
152u_unfilled_generator(enum pipe_prim_type prim,
153                     unsigned start,
154                     unsigned nr,
155                     unsigned unfilled_mode,
156                     enum pipe_prim_type *out_prim,
157                     unsigned *out_index_size,
158                     unsigned *out_nr,
159                     u_generate_func *out_generate);
160
161#endif
162