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.
40 #include "glimports.h"
48 size = 0; pts = 0; numverts = 0;
49 tinterp = &t; binterp = &b;
54 if( pts ) delete[] pts;
58 Trimline::init( TrimVertex *v )
66 Trimline::grow( long npts )
70 if( pts ) delete[] pts;
71 pts = new TrimVertex_p[size];
76 Trimline::append( TrimVertex *v )
78 assert( numverts != size );
83 Trimline::init( long npts, Arc_ptr jarc, long last )
85 jarcl.init( jarc, 0, last );
92 TrimVertex *tmp=tinterp;
100 *binterp = *jarcl.getnextpt();
104 Trimline::getPrevPt()
106 *binterp = *jarcl.getprevpt();
109 /*----------------------------------------------------------------------
110 * getNextPts - make arrays of pointers to trim points on left and right
111 * hulls of trim strip.
112 *----------------------------------------------------------------------
115 Trimline::getNextPts( REAL vval, Backend& backend )
117 reset(); swap(); append( tinterp );
118 assert( tinterp->param[1] >= vval );
120 register TrimVertex *p;
121 for( p=jarcl.getnextpt() ; p->param[1] >= vval; p=jarcl.getnextpt() ) {
125 /* compute and copy pointer to final point on left hull */
126 if( interpvert( last(), p, binterp, vval ) ) {
127 binterp->nuid = p->nuid;
128 backend.triangle( p, binterp, last() );
132 (void) jarcl.getprevpt(); /* reset jarcl to proper position */
137 Trimline::getPrevPts( REAL vval, Backend& backend )
139 reset(); swap(); append( tinterp );
140 assert( tinterp->param[1] >= vval );
142 register TrimVertex *q;
143 for( q=jarcl.getprevpt(); q->param[1] >= vval; q=jarcl.getprevpt() ) {
147 /* compute and copy pointer to final point on right hull */
148 if( interpvert( q, last(), binterp, vval ) ) {
149 binterp->nuid = q->nuid;
150 backend.triangle( last(), binterp, q );
154 (void) jarcl.getnextpt(); /* reset jarcl to proper position */
159 Trimline::getNextPts( Arc_ptr botarc )
161 reset(); swap(); append( tinterp );
164 PwlArc *lastpwl = botarc->prev->pwlArc;
165 TrimVertex *lastpt1 = &lastpwl->pts[lastpwl->npts-1];
167 TrimVertex *lastpt2 = botarc->pwlArc->pts;
168 register TrimVertex *p = jarcl.getnextpt();
169 for( append( p ); p != lastpt2; append( p ) ) {
170 assert( p != lastpt1 );
171 p = jarcl.getnextpt();
176 Trimline::getPrevPts( Arc_ptr botarc )
178 reset(); swap(); append( tinterp );
180 PwlArc *lastpwl = botarc->prev->pwlArc;
181 TrimVertex *lastpt1 = &lastpwl->pts[lastpwl->npts-1];
183 TrimVertex *lastpt2 = botarc->pwlArc->pts;
186 register TrimVertex *q = jarcl.getprevpt();
187 for( append( q ); q != lastpt1; append( q ) ) {
188 assert( q != lastpt2 );
189 q = jarcl.getprevpt();
195 Trimline::interpvert( TrimVertex *a, TrimVertex *b, TrimVertex *c, REAL vval )
197 REAL denom = a->param[1] - b->param[1];
200 if( vval == a->param[1] ) {
201 c->param[0] = a->param[0];
202 c->param[1] = a->param[1];
205 } else if( vval == b->param[1] ) {
206 c->param[0] = b->param[0];
207 c->param[1] = b->param[1];
211 REAL r = (a->param[1] - vval)/denom;
212 c->param[0] = a->param[0] - r * (a->param[0] - b->param[0]);
217 c->param[0] = a->param[0];
218 c->param[1] = a->param[1];