SGI SI GLU library

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diff --git a/src/glu/sgi/libnurbs/internals/varray.cc b/src/glu/sgi/libnurbs/internals/varray.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.
+*/
+
+/*
+ * varray.c++
+ *
+ * $Date: 2001/03/17 00:25:41 $ $Revision: 1.1 $
+ * $Header: /home/krh/git/sync/mesa-cvs-repo/Mesa/src/glu/sgi/libnurbs/internals/varray.cc,v 1.1 2001/03/17 00:25:41 brianp Exp $
+ */
+
+#include "glimports.h"
+#include "myassert.h"
+#include "mystdio.h"
+#include "varray.h"
+#include "arc.h"
+#include "math.h"         // fabs()
+
+#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( fabs(left->tail()[1] - botarc->tail()[1]) < TINY) goto end;
+            if( fabs(left->tail()[0]-right->prev->tail()[0]) < TINY &&
+                fabs(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;
+}
+