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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.
+*/
+
+/*
+ * varray.c++
+ *
+ */
+
+#include "glimports.h"
+#include "myassert.h"
+#include "mystdio.h"
+#include "varray.h"
+#include "arc.h"
+#include "simplemath.h" // glu_abs()
+
+#define TINY 0.0001
+inline long sgn( REAL x )
+{
+ return (x < -TINY) ? -1 : ((x > TINY) ? 1 : 0 );
+}
+
+
+Varray::Varray( void )
+{
+ varray = 0;
+ size = 0;
+}
+
+Varray::~Varray( void )
+{
+ if( varray ) delete[] varray;
+}
+
+inline void
+Varray::update( Arc_ptr arc, long dir[2], REAL val )
+{
+ register long ds = sgn(arc->tail()[0] - arc->prev->tail()[0]);
+ register long dt = sgn(arc->tail()[1] - arc->prev->tail()[1]);
+
+ if( dir[0] != ds || dir[1] != dt ) {
+ dir[0] = ds;
+ dir[1] = dt;
+ append( val );
+ }
+}
+
+void
+Varray::grow( long guess )
+{
+ if( size < guess ) {
+ size = guess * 2;
+ if( varray ) delete[] varray;
+ varray = new REAL[size];
+ assert( varray != 0 );
+ }
+}
+
+long
+Varray::init( REAL delta, Arc_ptr toparc, Arc_ptr botarc )
+{
+ Arc_ptr left = toparc->next;
+ Arc_ptr right = toparc;
+ long ldir[2], rdir[2];
+
+ ldir[0] = sgn( left->tail()[0] - left->prev->tail()[0] );
+ ldir[1] = sgn( left->tail()[1] - left->prev->tail()[1] );
+ rdir[0] = sgn( right->tail()[0] - right->prev->tail()[0] );
+ rdir[1] = sgn( right->tail()[1] - right->prev->tail()[1] );
+
+ vval[0] = toparc->tail()[1];
+ numquads = 0;
+
+ while( 1 ) {
+ switch( sgn( left->tail()[1] - right->prev->tail()[1] ) ) {
+ case 1:
+ left = left->next;
+ update( left, ldir, left->prev->tail()[1] );
+ break;
+ case -1:
+ right = right->prev;
+ update( right, rdir, right->tail()[1] );
+ break;
+ case 0:
+ if( glu_abs(left->tail()[1] - botarc->tail()[1]) < TINY) goto end;
+ if( glu_abs(left->tail()[0]-right->prev->tail()[0]) < TINY &&
+ glu_abs(left->tail()[1]-right->prev->tail()[1]) < TINY) goto end;
+ left = left->next;
+ break;
+ }
+ }
+
+end:
+ append( botarc->tail()[1] );
+
+ grow( ((long) ((vval[0] - vval[numquads])/delta)) + numquads + 2 );
+
+ long i, index = 0;
+ for( i=0; i<numquads; i++ ) {
+ voffset[i] = index;
+ varray[index++] = vval[i];
+ REAL dist = vval[i] - vval[i+1];
+ if( dist > delta ) {
+ long steps = ((long) (dist/delta)) +1;
+ float deltav = - dist / (REAL) steps;
+ for( long j=1; j<steps; j++ )
+ varray[index++] = vval[i] + j * deltav;
+ }
+ }
+ voffset[i] = index;
+ varray[index] = vval[i];
+ return index;
+}
+