xref: /aosp_15_r20/external/mesa3d/src/gallium/auxiliary/draw/draw_pt_util.c (revision 6104692788411f58d303aa86923a9ff6ecaded22)
1 /**************************************************************************
2  *
3  * Copyright 2007 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   * Authors:
30   *   Keith Whitwell <[email protected]>
31   */
32 
33 #include "draw/draw_context.h"
34 #include "draw/draw_private.h"
35 #include "draw/draw_pt.h"
36 #include "util/u_debug.h"
37 
38 
39 void
draw_pt_split_prim(enum mesa_prim prim,unsigned * first,unsigned * incr)40 draw_pt_split_prim(enum mesa_prim prim, unsigned *first, unsigned *incr)
41 {
42    switch (prim) {
43    case MESA_PRIM_POINTS:
44       *first = 1;
45       *incr = 1;
46       break;
47    case MESA_PRIM_LINES:
48       *first = 2;
49       *incr = 2;
50       break;
51    case MESA_PRIM_LINE_STRIP:
52    case MESA_PRIM_LINE_LOOP:
53       *first = 2;
54       *incr = 1;
55       break;
56    case MESA_PRIM_LINES_ADJACENCY:
57       *first = 4;
58       *incr = 4;
59       break;
60    case MESA_PRIM_LINE_STRIP_ADJACENCY:
61       *first = 4;
62       *incr = 1;
63       break;
64    case MESA_PRIM_TRIANGLES:
65       *first = 3;
66       *incr = 3;
67       break;
68    case MESA_PRIM_TRIANGLES_ADJACENCY:
69       *first = 6;
70       *incr = 6;
71       break;
72    case MESA_PRIM_TRIANGLE_STRIP:
73    case MESA_PRIM_TRIANGLE_FAN:
74    case MESA_PRIM_POLYGON:
75       *first = 3;
76       *incr = 1;
77       break;
78    case MESA_PRIM_TRIANGLE_STRIP_ADJACENCY:
79       *first = 6;
80       *incr = 2;
81       break;
82    case MESA_PRIM_QUADS:
83       *first = 4;
84       *incr = 4;
85       break;
86    case MESA_PRIM_QUAD_STRIP:
87       *first = 4;
88       *incr = 2;
89       break;
90    default:
91       assert(0);
92       *first = 0;
93       *incr = 1;		/* set to one so that count % incr works */
94       break;
95    }
96 }
97 
98 
99 unsigned
draw_pt_trim_count(unsigned count,unsigned first,unsigned incr)100 draw_pt_trim_count(unsigned count, unsigned first, unsigned incr)
101 {
102    if (count < first)
103       return 0;
104    return count - (count - first) % incr;
105 }
106