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.
36 ** Author: Eric Veach, July 1994.
45 #ifdef NO_BRANCH_CONDITIONS
46 /* MIPS architecture has special instructions to evaluate boolean
47 * conditions -- more efficient than branching, IF you can get the
48 * compiler to generate the right instructions (SGI compiler doesn't)
50 #define VertEq(u,v) (((u)->s == (v)->s) & ((u)->t == (v)->t))
51 #define VertLeq(u,v) (((u)->s < (v)->s) | \
52 ((u)->s == (v)->s & (u)->t <= (v)->t))
54 #define VertEq(u,v) ((u)->s == (v)->s && (u)->t == (v)->t)
55 #define VertLeq(u,v) (((u)->s < (v)->s) || \
56 ((u)->s == (v)->s && (u)->t <= (v)->t))
59 #define EdgeEval(u,v,w) __gl_edgeEval(u,v,w)
60 #define EdgeSign(u,v,w) __gl_edgeSign(u,v,w)
62 /* Versions of VertLeq, EdgeSign, EdgeEval with s and t transposed. */
64 #define TransLeq(u,v) (((u)->t < (v)->t) || \
65 ((u)->t == (v)->t && (u)->s <= (v)->s))
66 #define TransEval(u,v,w) __gl_transEval(u,v,w)
67 #define TransSign(u,v,w) __gl_transSign(u,v,w)
70 #define EdgeGoesLeft(e) VertLeq( (e)->Dst, (e)->Org )
71 #define EdgeGoesRight(e) VertLeq( (e)->Org, (e)->Dst )
74 #define ABS(x) ((x) < 0 ? -(x) : (x))
75 #define VertL1dist(u,v) (ABS(u->s - v->s) + ABS(u->t - v->t))
77 #define VertCCW(u,v,w) __gl_vertCCW(u,v,w)
79 int __gl_vertLeq( GLUvertex
*u
, GLUvertex
*v
);
80 GLdouble
__gl_edgeEval( GLUvertex
*u
, GLUvertex
*v
, GLUvertex
*w
);
81 GLdouble
__gl_edgeSign( GLUvertex
*u
, GLUvertex
*v
, GLUvertex
*w
);
82 GLdouble
__gl_transEval( GLUvertex
*u
, GLUvertex
*v
, GLUvertex
*w
);
83 GLdouble
__gl_transSign( GLUvertex
*u
, GLUvertex
*v
, GLUvertex
*w
);
84 int __gl_vertCCW( GLUvertex
*u
, GLUvertex
*v
, GLUvertex
*w
);
85 void __gl_edgeIntersect( GLUvertex
*o1
, GLUvertex
*d1
,
86 GLUvertex
*o2
, GLUvertex
*d2
,