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** License Applicability. Except to the extent portions of this file are
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** made subject to an alternative license as permitted in the SGI Free
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** Software License B, Version 1.1 (the "License"), the contents of this
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** file are subject only to the provisions of the License. You may not use
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** this file except in compliance with the License. You may obtain a copy
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** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
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** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
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** 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
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** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
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** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
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** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
18
** Original Code. The Original Code is: OpenGL Sample Implementation,
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** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
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** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
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** Copyright in any portions created by third parties is as indicated
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** elsewhere herein. All Rights Reserved.
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** Additional Notice Provisions: The application programming interfaces
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** established by SGI in conjunction with the Original Code are The
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** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
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** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
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** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
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** Window System(R) (Version 1.3), released October 19, 1998. This software
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** was created using the OpenGL(R) version 1.2.1 Sample Implementation
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** published by SGI, but has not been independently verified as being
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** compliant with the OpenGL(R) version 1.2.1 Specification.
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* $Header: //depot/main/gfx/lib/glu/libnurbs/internals/varray.cc#4 $
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#include "glimports.h"
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#include "math.h" // fabs()
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inline long sgn( REAL x )
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return (x < -TINY) ? -1 : ((x > TINY) ? 1 : 0 );
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Varray::Varray( void )
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Varray::~Varray( void )
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if( varray ) delete[] varray;
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Varray::update( Arc_ptr arc, long dir[2], REAL val )
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register long ds = sgn(arc->tail()[0] - arc->prev->tail()[0]);
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register long dt = sgn(arc->tail()[1] - arc->prev->tail()[1]);
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if( dir[0] != ds || dir[1] != dt ) {
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Varray::grow( long guess )
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if( varray ) delete[] varray;
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varray = new REAL[size];
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assert( varray != 0 );
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Varray::init( REAL delta, Arc_ptr toparc, Arc_ptr botarc )
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Arc_ptr left = toparc->next;
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Arc_ptr right = toparc;
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long ldir[2], rdir[2];
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ldir[0] = sgn( left->tail()[0] - left->prev->tail()[0] );
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ldir[1] = sgn( left->tail()[1] - left->prev->tail()[1] );
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rdir[0] = sgn( right->tail()[0] - right->prev->tail()[0] );
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rdir[1] = sgn( right->tail()[1] - right->prev->tail()[1] );
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vval[0] = toparc->tail()[1];
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switch( sgn( left->tail()[1] - right->prev->tail()[1] ) ) {
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update( left, ldir, left->prev->tail()[1] );
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update( right, rdir, right->tail()[1] );
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if( fabs(left->tail()[1] - botarc->tail()[1]) < TINY) goto end;
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if( fabs(left->tail()[0]-right->prev->tail()[0]) < TINY &&
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fabs(left->tail()[1]-right->prev->tail()[1]) < TINY) goto end;
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append( botarc->tail()[1] );
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grow( ((long) ((vval[0] - vval[numquads])/delta)) + numquads + 2 );
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for( i=0; i<numquads; i++ ) {
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varray[index++] = vval[i];
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REAL dist = vval[i] - vval[i+1];
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long steps = ((long) (dist/delta)) +1;
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float deltav = - dist / (REAL) steps;
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for( long j=1; j<steps; j++ )
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varray[index++] = vval[i] + j * deltav;
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varray[index] = vval[i];