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diff --git a/mesalib/src/glu/sgi/libnurbs/internals/trimline.cc b/mesalib/src/glu/sgi/libnurbs/internals/trimline.cc
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+++ b/mesalib/src/glu/sgi/libnurbs/internals/trimline.cc
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+/*
+** License Applicability. Except to the extent portions of this file are
+** made subject to an alternative license as permitted in the SGI Free
+** Software License B, Version 1.1 (the "License"), the contents of this
+** file are subject only to the provisions of the License. You may not use
+** this file except in compliance with the License. You may obtain a copy
+** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
+** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
+**
+** http://oss.sgi.com/projects/FreeB
+**
+** Note that, as provided in the License, the Software is distributed on an
+** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
+** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
+** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
+** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
+**
+** Original Code. The Original Code is: OpenGL Sample Implementation,
+** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
+** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
+** Copyright in any portions created by third parties is as indicated
+** elsewhere herein. All Rights Reserved.
+**
+** Additional Notice Provisions: The application programming interfaces
+** established by SGI in conjunction with the Original Code are The
+** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
+** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
+** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
+** Window System(R) (Version 1.3), released October 19, 1998. This software
+** was created using the OpenGL(R) version 1.2.1 Sample Implementation
+** published by SGI, but has not been independently verified as being
+** compliant with the OpenGL(R) version 1.2.1 Specification.
+*/
+
+/*
+ * trimline.c++
+ *
+ */
+
+#include "glimports.h"
+#include "myassert.h"
+#include "mystdio.h"
+#include "trimline.h"
+#include "backend.h"
+
+Trimline::Trimline()
+{
+ size = 0; pts = 0; numverts = 0;
+ tinterp = &t; binterp = &b;
+}
+
+Trimline::~Trimline()
+{
+ if( pts ) delete[] pts;
+}
+
+void
+Trimline::init( TrimVertex *v )
+{
+ reset();
+ grow(1);
+ append(v);
+}
+
+inline void
+Trimline::grow( long npts )
+{
+ if( size < npts ) {
+ size = 2 * npts;
+ if( pts ) delete[] pts;
+ pts = new TrimVertex_p[size];
+ }
+}
+
+inline void
+Trimline::append( TrimVertex *v )
+{
+ assert( numverts != size );
+ pts[numverts++] = v;
+}
+
+void
+Trimline::init( long npts, Arc_ptr jarc, long last )
+{
+ jarcl.init( jarc, 0, last );
+ grow( npts + 2 );
+}
+
+inline void
+Trimline::swap()
+{
+ TrimVertex *tmp=tinterp;
+ tinterp=binterp;
+ binterp=tmp;
+}
+
+void
+Trimline::getNextPt()
+{
+ *binterp = *jarcl.getnextpt();
+}
+
+void
+Trimline::getPrevPt()
+{
+ *binterp = *jarcl.getprevpt();
+}
+
+/*----------------------------------------------------------------------
+ * getNextPts - make arrays of pointers to trim points on left and right
+ * hulls of trim strip.
+ *----------------------------------------------------------------------
+ */
+void
+Trimline::getNextPts( REAL vval, Backend& backend )
+{
+ reset(); swap(); append( tinterp );
+ assert( tinterp->param[1] >= vval );
+
+ register TrimVertex *p;
+ for( p=jarcl.getnextpt() ; p->param[1] >= vval; p=jarcl.getnextpt() ) {
+ append( p );
+ }
+
+ /* compute and copy pointer to final point on left hull */
+ if( interpvert( last(), p, binterp, vval ) ) {
+ binterp->nuid = p->nuid;
+ backend.triangle( p, binterp, last() );
+ append( binterp );
+ }
+ jarcl.reverse();
+ (void) jarcl.getprevpt(); /* reset jarcl to proper position */
+ jarcl.reverse();
+}
+
+void
+Trimline::getPrevPts( REAL vval, Backend& backend )
+{
+ reset(); swap(); append( tinterp );
+ assert( tinterp->param[1] >= vval );
+
+ register TrimVertex *q;
+ for( q=jarcl.getprevpt(); q->param[1] >= vval; q=jarcl.getprevpt() ) {
+ append( q );
+ }
+
+ /* compute and copy pointer to final point on right hull */
+ if( interpvert( q, last(), binterp, vval ) ) {
+ binterp->nuid = q->nuid;
+ backend.triangle( last(), binterp, q );
+ append( binterp );
+ }
+ jarcl.reverse();
+ (void) jarcl.getnextpt(); /* reset jarcl to proper position */
+ jarcl.reverse();
+}
+
+void
+Trimline::getNextPts( Arc_ptr botarc )
+{
+ reset(); swap(); append( tinterp );
+
+#ifndef NDEBUG
+ PwlArc *lastpwl = botarc->prev->pwlArc;
+ TrimVertex *lastpt1 = &lastpwl->pts[lastpwl->npts-1];
+#endif
+ TrimVertex *lastpt2 = botarc->pwlArc->pts;
+ register TrimVertex *p = jarcl.getnextpt();
+ for( append( p ); p != lastpt2; append( p ) ) {
+ assert( p != lastpt1 );
+ p = jarcl.getnextpt();
+ }
+}
+
+void
+Trimline::getPrevPts( Arc_ptr botarc )
+{
+ reset(); swap(); append( tinterp );
+
+ PwlArc *lastpwl = botarc->prev->pwlArc;
+ TrimVertex *lastpt1 = &lastpwl->pts[lastpwl->npts-1];
+#ifndef NDEBUG
+ TrimVertex *lastpt2 = botarc->pwlArc->pts;
+#endif
+
+ register TrimVertex *q = jarcl.getprevpt();
+ for( append( q ); q != lastpt1; append( q ) ) {
+ assert( q != lastpt2 );
+ q = jarcl.getprevpt();
+ }
+}
+
+
+long
+Trimline::interpvert( TrimVertex *a, TrimVertex *b, TrimVertex *c, REAL vval )
+{
+ REAL denom = a->param[1] - b->param[1];
+
+ if(denom != 0) {
+ if( vval == a->param[1] ) {
+ c->param[0] = a->param[0];
+ c->param[1] = a->param[1];
+ c->nuid = a->nuid;
+ return 0;
+ } else if( vval == b->param[1] ) {
+ c->param[0] = b->param[0];
+ c->param[1] = b->param[1];
+ c->nuid = b->nuid;
+ return 0;
+ } else {
+ REAL r = (a->param[1] - vval)/denom;
+ c->param[0] = a->param[0] - r * (a->param[0] - b->param[0]);
+ c->param[1] = vval;
+ return 1;
+ }
+ } else {
+ c->param[0] = a->param[0];
+ c->param[1] = a->param[1];
+ c->nuid = a->nuid;
+ return 0;
+ }
+}
+