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:
10 ** http://oss.sgi.com/projects/FreeB
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.
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.
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.
38 * $Date$ $Revision: 1.1 $
39 * $Header: /cygdrive/c/RCVS/CVS/ReactOS/reactos/lib/glu32/libnurbs/internals/curvesub.cc,v 1.1 2004/02/02 16:39:11 navaraf Exp $
42 #include "glimports.h"
45 #include "subdivider.h"
46 #include "renderhints.h"
49 #include "curvelist.h"
51 #include "nurbsconsts.h"
53 /*--------------------------------------------------------------------------
54 * drawCurves - main curve rendering entry point
55 *--------------------------------------------------------------------------
59 Subdivider::drawCurves( void )
63 qlist
->getRange( from
, to
, bpts
);
68 for( int i
=bpts
.start
; i
<bpts
.end
-1; i
++ ) {
73 qlist
->downloadAll( &pta
, &ptb
, backend
);
75 Curvelist
curvelist( qlist
, pta
, ptb
);
76 samplingSplit( curvelist
, renderhints
.maxsubdivisions
);
82 /*--------------------------------------------------------------------------
83 * samplingSplit - recursively subdivide patch, cull check each subpatch
84 *--------------------------------------------------------------------------
88 Subdivider::samplingSplit( Curvelist
& curvelist
, int subdivisions
)
90 if( curvelist
.cullCheck() == CULL_TRIVIAL_REJECT
) return;
92 curvelist
.getstepsize();
94 if( curvelist
.needsSamplingSubdivision() && (subdivisions
> 0) ) {
95 REAL mid
= ( curvelist
.range
[0] + curvelist
.range
[1] ) * 0.5;
96 Curvelist
lowerlist( curvelist
, mid
);
97 samplingSplit( lowerlist
, subdivisions
-1 ); // lower
98 samplingSplit( curvelist
, subdivisions
-1 ); // upper
100 long nu
= 1 + ((long) (curvelist
.range
[2] / curvelist
.stepsize
));
101 backend
.curvgrid( curvelist
.range
[0], curvelist
.range
[1], nu
);
102 backend
.curvmesh( 0, nu
);