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];