4aeb5eeac16ddf44d092dc6e12db473f4e3e2297
[reactos.git] / reactos / dll / opengl / glu32 / src / libnurbs / internals / trimregion.cc
1 /*
2 ** License Applicability. Except to the extent portions of this file are
3 ** made subject to an alternative license as permitted in the SGI Free
4 ** Software License B, Version 1.1 (the "License"), the contents of this
5 ** file are subject only to the provisions of the License. You may not use
6 ** this file except in compliance with the License. You may obtain a copy
7 ** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
8 ** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
9 **
10 ** http://oss.sgi.com/projects/FreeB
11 **
12 ** Note that, as provided in the License, the Software is distributed on an
13 ** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
14 ** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
15 ** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
16 ** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
17 **
18 ** Original Code. The Original Code is: OpenGL Sample Implementation,
19 ** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
20 ** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
21 ** Copyright in any portions created by third parties is as indicated
22 ** elsewhere herein. All Rights Reserved.
23 **
24 ** Additional Notice Provisions: The application programming interfaces
25 ** established by SGI in conjunction with the Original Code are The
26 ** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
27 ** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
28 ** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
29 ** Window System(R) (Version 1.3), released October 19, 1998. This software
30 ** was created using the OpenGL(R) version 1.2.1 Sample Implementation
31 ** published by SGI, but has not been independently verified as being
32 ** compliant with the OpenGL(R) version 1.2.1 Specification.
33 */
34
35 /*
36 * trimregion.c++
37 *
38 */
39
40 #include "glimports.h"
41 #include "myassert.h"
42 #include "mystdio.h"
43 #include "trimregion.h"
44
45 TrimRegion::TrimRegion( void )
46 {
47 }
48
49 void
50 TrimRegion::setDu( REAL du )
51 {
52 oneOverDu = 1.0/du;
53 }
54
55 void
56 TrimRegion::init( long npts, Arc_ptr extrema )
57 {
58 left.init( npts, extrema, extrema->pwlArc->npts - 1 );
59 left.getNextPt();
60
61 right.init( npts, extrema, 0 );
62 right.getPrevPt();
63 }
64
65 void
66 TrimRegion::getPts( Arc_ptr extrema )
67 {
68 left.getNextPts( extrema );
69 right.getPrevPts( extrema );
70 }
71
72 void
73 TrimRegion::getPts( Backend &backend )
74 {
75 left.getNextPts( bot.vval, backend );
76 right.getPrevPts( bot.vval, backend );
77 }
78
79 void
80 TrimRegion::getGridExtent( void )
81 {
82 getGridExtent( left.last(), right.last() );
83 }
84
85 void
86 TrimRegion::getGridExtent( TrimVertex *l, TrimVertex *r )
87 {
88 bot.ustart = (long) ((l->param[0] - uarray.uarray[0])*oneOverDu);
89 if( l->param[0] >= uarray.uarray[bot.ustart] ) bot.ustart++;
90 // if( l->param[0] > uarray.uarray[bot.ustart] ) bot.ustart++;
91 assert( l->param[0] <= uarray.uarray[bot.ustart] );
92 assert( l->param[0] >= uarray.uarray[bot.ustart-1] );
93
94 bot.uend = (long) ((r->param[0] - uarray.uarray[0])*oneOverDu);
95 if( uarray.uarray[bot.uend] >= r->param[0] ) bot.uend--;
96 // if( uarray.uarray[bot.uend] > r->param[0] ) bot.uend--;
97 assert( r->param[0] >= uarray.uarray[bot.uend] );
98 assert( r->param[0] <= uarray.uarray[bot.uend+1] );
99 }
100
101 int
102 TrimRegion::canTile( void )
103 {
104 TrimVertex *lf = left.first();
105 TrimVertex *ll = left.last();
106 TrimVertex *l = ( ll->param[0] > lf->param[0] ) ? ll : lf;
107
108 TrimVertex *rf = right.first();
109 TrimVertex *rl = right.last();
110 TrimVertex *r = ( rl->param[0] < rf->param[0] ) ? rl : rf;
111 return (l->param[0] <= r->param[0]) ? 1 : 0;
112 }
113