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 ** Author: Eric Veach, July 1994. 37 ** 38 ** $Date$ $Revision$ 39 ** $Header: //depot/main/gfx/lib/glu/libtess/geom.h#5 $ 40 */ 41 42 #ifndef __geom_h_ 43 #define __geom_h_ 44 45 #include "mesh.h" 46 47 #ifdef NO_BRANCH_CONDITIONS 48 /* MIPS architecture has special instructions to evaluate boolean 49 * conditions -- more efficient than branching, IF you can get the 50 * compiler to generate the right instructions (SGI compiler doesn't) 51 */ 52 #define VertEq(u,v) (((u)->s == (v)->s) & ((u)->t == (v)->t)) 53 #define VertLeq(u,v) (((u)->s < (v)->s) | \ 54 ((u)->s == (v)->s & (u)->t <= (v)->t)) 55 #else 56 #define VertEq(u,v) ((u)->s == (v)->s && (u)->t == (v)->t) 57 #define VertLeq(u,v) (((u)->s < (v)->s) || \ 58 ((u)->s == (v)->s && (u)->t <= (v)->t)) 59 #endif 60 61 #define EdgeEval(u,v,w) __gl_edgeEval(u,v,w) 62 #define EdgeSign(u,v,w) __gl_edgeSign(u,v,w) 63 64 /* Versions of VertLeq, EdgeSign, EdgeEval with s and t transposed. */ 65 66 #define TransLeq(u,v) (((u)->t < (v)->t) || \ 67 ((u)->t == (v)->t && (u)->s <= (v)->s)) 68 #define TransEval(u,v,w) __gl_transEval(u,v,w) 69 #define TransSign(u,v,w) __gl_transSign(u,v,w) 70 71 72 #define EdgeGoesLeft(e) VertLeq( (e)->Dst, (e)->Org ) 73 #define EdgeGoesRight(e) VertLeq( (e)->Org, (e)->Dst ) 74 75 #define ABS(x) ((x) < 0 ? -(x) : (x)) 76 #define VertL1dist(u,v) (ABS(u->s - v->s) + ABS(u->t - v->t)) 77 78 #define VertCCW(u,v,w) __gl_vertCCW(u,v,w) 79 80 int __gl_vertLeq( GLUvertex *u, GLUvertex *v ); 81 GLdouble __gl_edgeEval( GLUvertex *u, GLUvertex *v, GLUvertex *w ); 82 GLdouble __gl_edgeSign( GLUvertex *u, GLUvertex *v, GLUvertex *w ); 83 GLdouble __gl_transEval( GLUvertex *u, GLUvertex *v, GLUvertex *w ); 84 GLdouble __gl_transSign( GLUvertex *u, GLUvertex *v, GLUvertex *w ); 85 int __gl_vertCCW( GLUvertex *u, GLUvertex *v, GLUvertex *w ); 86 void __gl_edgeIntersect( GLUvertex *o1, GLUvertex *d1, 87 GLUvertex *o2, GLUvertex *d2, 88 GLUvertex *v ); 89 90 #endif 91