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
26/*
27 * NOTE: This file is not compiled by itself.  It's actually #included
28 * by the generated u_unfilled_gen.c file!
29 */
30
31#include "u_indices.h"
32#include "u_indices_priv.h"
33#include "util/u_prim.h"
34
35
36static void translate_ubyte_ushort( const void *in,
37                                    unsigned start,
38                                    unsigned in_nr,
39                                    unsigned out_nr,
40                                    unsigned restart_index,
41                                    void *out )
42{
43   const ubyte *in_ub = (const ubyte *)in;
44   ushort *out_us = (ushort *)out;
45   unsigned i;
46   for (i = 0; i < out_nr; i++)
47      out_us[i] = (ushort) in_ub[i+start];
48}
49
50static void translate_memcpy_ushort( const void *in,
51                                     unsigned start,
52                                     unsigned in_nr,
53                                     unsigned out_nr,
54                                     unsigned restart_index,
55                                     void *out )
56{
57   memcpy(out, &((short *)in)[start], out_nr*sizeof(short));
58}
59
60static void translate_memcpy_uint( const void *in,
61                                   unsigned start,
62                                   unsigned in_nr,
63                                   unsigned out_nr,
64                                   unsigned restart_index,
65                                   void *out )
66{
67   memcpy(out, &((int *)in)[start], out_nr*sizeof(int));
68}
69
70
71static void generate_linear_ushort( unsigned start,
72                                    unsigned nr,
73                                    void *out )
74{
75   ushort *out_us = (ushort *)out;
76   unsigned i;
77   for (i = 0; i < nr; i++)
78      out_us[i] = (ushort)(i + start);
79}
80
81static void generate_linear_uint( unsigned start,
82                                  unsigned nr,
83                                  void *out )
84{
85   unsigned *out_ui = (unsigned *)out;
86   unsigned i;
87   for (i = 0; i < nr; i++)
88      out_ui[i] = i + start;
89}
90
91
92/**
93 * Given a primitive type and number of vertices, return the number of vertices
94 * needed to draw the primitive with fill mode = PIPE_POLYGON_MODE_LINE using
95 * separate lines (PIPE_PRIM_LINES).
96 */
97static unsigned
98nr_lines(enum pipe_prim_type prim, unsigned nr)
99{
100   switch (prim) {
101   case PIPE_PRIM_TRIANGLES:
102      return (nr / 3) * 6;
103   case PIPE_PRIM_TRIANGLE_STRIP:
104      return (nr - 2) * 6;
105   case PIPE_PRIM_TRIANGLE_FAN:
106      return (nr - 2)  * 6;
107   case PIPE_PRIM_QUADS:
108      return (nr / 4) * 8;
109   case PIPE_PRIM_QUAD_STRIP:
110      return (nr - 2) / 2 * 8;
111   case PIPE_PRIM_POLYGON:
112      return 2 * nr; /* a line (two verts) for each polygon edge */
113   /* Note: these cases can't really be handled since drawing lines instead
114    * of triangles would also require changing the GS.  But if there's no GS,
115    * this should work.
116    */
117   case PIPE_PRIM_TRIANGLES_ADJACENCY:
118      return (nr / 6) * 6;
119   case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
120      return ((nr - 4) / 2) * 6;
121   default:
122      assert(0);
123      return 0;
124   }
125}
126
127
128enum indices_mode
129u_unfilled_translator(enum pipe_prim_type prim,
130                      unsigned in_index_size,
131                      unsigned nr,
132                      unsigned unfilled_mode,
133                      enum pipe_prim_type *out_prim,
134                      unsigned *out_index_size,
135                      unsigned *out_nr,
136                      u_translate_func *out_translate)
137{
138   unsigned in_idx;
139   unsigned out_idx;
140
141   assert(u_reduced_prim(prim) == PIPE_PRIM_TRIANGLES);
142
143   u_unfilled_init();
144
145   in_idx = in_size_idx(in_index_size);
146   *out_index_size = (in_index_size == 4) ? 4 : 2;
147   out_idx = out_size_idx(*out_index_size);
148
149   if (unfilled_mode == PIPE_POLYGON_MODE_POINT) {
150      *out_prim = PIPE_PRIM_POINTS;
151      *out_nr = nr;
152
153      switch (in_index_size) {
154      case 1:
155         *out_translate = translate_ubyte_ushort;
156         return U_TRANSLATE_NORMAL;
157      case 2:
158         *out_translate = translate_memcpy_uint;
159         return U_TRANSLATE_MEMCPY;
160      case 4:
161         *out_translate = translate_memcpy_ushort;
162         return U_TRANSLATE_MEMCPY;
163      default:
164         *out_translate = translate_memcpy_uint;
165         *out_nr = 0;
166         assert(0);
167         return U_TRANSLATE_ERROR;
168      }
169   }
170   else {
171      assert(unfilled_mode == PIPE_POLYGON_MODE_LINE);
172      *out_prim = PIPE_PRIM_LINES;
173      *out_translate = translate_line[in_idx][out_idx][prim];
174      *out_nr = nr_lines( prim, nr );
175      return U_TRANSLATE_NORMAL;
176   }
177}
178
179
180/**
181 * Utility for converting unfilled polygons into points, lines, triangles.
182 * Few drivers have direct support for OpenGL's glPolygonMode.
183 * This function helps with converting triangles into points or lines
184 * when the front and back fill modes are the same.  When there's
185 * different front/back fill modes, that can be handled with the
186 * 'draw' module.
187 */
188enum indices_mode
189u_unfilled_generator(enum pipe_prim_type prim,
190                     unsigned start,
191                     unsigned nr,
192                     unsigned unfilled_mode,
193                     enum pipe_prim_type *out_prim,
194                     unsigned *out_index_size,
195                     unsigned *out_nr,
196                     u_generate_func *out_generate)
197{
198   unsigned out_idx;
199
200   assert(u_reduced_prim(prim) == PIPE_PRIM_TRIANGLES);
201
202   u_unfilled_init();
203
204   *out_index_size = ((start + nr) > 0xfffe) ? 4 : 2;
205   out_idx = out_size_idx(*out_index_size);
206
207   if (unfilled_mode == PIPE_POLYGON_MODE_POINT) {
208      if (*out_index_size == 4)
209         *out_generate = generate_linear_uint;
210      else
211         *out_generate = generate_linear_ushort;
212
213      *out_prim = PIPE_PRIM_POINTS;
214      *out_nr = nr;
215      return U_GENERATE_LINEAR;
216   }
217   else {
218      assert(unfilled_mode == PIPE_POLYGON_MODE_LINE);
219      *out_prim = PIPE_PRIM_LINES;
220      *out_generate = generate_line[out_idx][prim];
221      *out_nr = nr_lines( prim, nr );
222
223      return U_GENERATE_REUSABLE;
224   }
225}
226