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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++
*
* $Date: 2002/11/01 23:35:07 $ $Revision: 1.2 $
* $Header: /home/krh/git/sync/mesa-cvs-repo/Mesa/src/glu/sgi/libnurbs/internals/varray.cc,v 1.2 2002/11/01 23:35:07 brianp Exp $
*/
#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;
}
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