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diff --git a/mesalib/src/glu/sgi/libnurbs/internals/curve.cc b/mesalib/src/glu/sgi/libnurbs/internals/curve.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.
+*/
+
+/*
+ * curve.c++
+ *
+ */
+
+#include "glimports.h"
+#include "myassert.h"
+#include "mystdio.h"
+#include "mymath.h"
+#include "curve.h"
+#include "mapdesc.h"
+#include "types.h"
+#include "quilt.h"
+#include "nurbsconsts.h"
+
+/*--------------------------------------------------------------------------
+ * Curve::Curve - copy curve from quilt and transform control points
+ *--------------------------------------------------------------------------
+ */
+
+Curve::Curve( Quilt_ptr geo, REAL pta, REAL ptb, Curve *c )
+{
+ mapdesc = geo->mapdesc;
+ next = c;
+ needsSampling = mapdesc->isRangeSampling() ? 1 : 0;
+ cullval = mapdesc->isCulling() ? CULL_ACCEPT : CULL_TRIVIAL_ACCEPT;
+ order = geo->qspec[0].order;
+ stride = MAXCOORDS;
+
+ REAL *ps = geo->cpts;
+ Quiltspec_ptr qs = geo->qspec;
+ ps += qs->offset;
+ ps += qs->index * qs->order * qs->stride;
+
+ if( needsSampling )
+ mapdesc->xformSampling( ps, qs->order, qs->stride, spts, stride );
+
+ if( cullval == CULL_ACCEPT )
+ mapdesc->xformCulling( ps, qs->order, qs->stride, cpts, stride );
+
+ /* set untrimmed curve range */
+ range[0] = qs->breakpoints[qs->index];
+ range[1] = qs->breakpoints[qs->index+1];
+ range[2] = range[1] - range[0];
+
+ if( range[0] != pta ) {
+ Curve lower( *this, pta, 0 );
+ lower.next = next;
+ *this = lower;
+ }
+ if( range[1] != ptb ) {
+ Curve lower( *this, ptb, 0 );
+ }
+}
+
+/*--------------------------------------------------------------------------
+ * Curve::Curve - subdivide a curve along an isoparametric line
+ *--------------------------------------------------------------------------
+ */
+
+Curve::Curve( Curve& upper, REAL value, Curve *c )
+{
+ Curve &lower = *this;
+
+ lower.next = c;
+ lower.mapdesc = upper.mapdesc;
+ lower.needsSampling = upper.needsSampling;
+ lower.order = upper.order;
+ lower.stride = upper.stride;
+ lower.cullval = upper.cullval;
+
+ REAL d = (value - upper.range[0]) / upper.range[2];
+
+ if( needsSampling )
+ mapdesc->subdivide( upper.spts, lower.spts, d, upper.stride, upper.order );
+
+ if( cullval == CULL_ACCEPT )
+ mapdesc->subdivide( upper.cpts, lower.cpts, d, upper.stride, upper.order );
+
+ lower.range[0] = upper.range[0];
+ lower.range[1] = value;
+ lower.range[2] = value - upper.range[0];
+ upper.range[0] = value;
+ upper.range[2] = upper.range[1] - value;
+}
+
+
+/*--------------------------------------------------------------------------
+ * Curve::clamp - clamp the sampling rate to a given maximum
+ *--------------------------------------------------------------------------
+ */
+
+void
+Curve::clamp( void )
+{
+ if( stepsize < minstepsize )
+ stepsize = mapdesc->clampfactor * minstepsize;
+}
+
+void
+Curve::setstepsize( REAL max )
+{
+ stepsize = ( max >= 1.0 ) ? (range[2] / max) : range[2];
+ minstepsize = stepsize;
+}
+
+void
+Curve::getstepsize( void )
+{
+ minstepsize= 0;
+
+ if( mapdesc->isConstantSampling() ) {
+ // fixed number of samples per patch in each direction
+ // maxrate is number of s samples per patch
+ setstepsize( mapdesc->maxrate );
+ } else if( mapdesc->isDomainSampling() ) {
+ // maxrate is number of s samples per unit s length of domain
+ setstepsize( mapdesc->maxrate * range[2] );
+ } else {
+ // upper bound on path length between sample points
+
+ assert( order <= MAXORDER );
+
+ /* points have been transformed, therefore they are homogeneous */
+ REAL tmp[MAXORDER][MAXCOORDS];
+ const int tstride = sizeof(tmp[0]) / sizeof(REAL);
+ int val = mapdesc->project( spts, stride, &tmp[0][0], tstride, order );
+
+ if( val == 0 ) {
+ // control points cross infinity, therefore derivatives are undefined
+ setstepsize( mapdesc->maxrate );
+ } else {
+ REAL t = mapdesc->getProperty( N_PIXEL_TOLERANCE );
+ if( mapdesc->isParametricDistanceSampling() ) {
+ REAL d = mapdesc->calcPartialVelocity( &tmp[0][0], tstride, order, 2, range[2] );
+ stepsize = (d > 0.0) ? sqrtf( 8.0 * t / d ) : range[2];
+ minstepsize = ( mapdesc->maxrate > 0.0 ) ? (range[2] / mapdesc->maxrate) : 0.0;
+ } else if( mapdesc->isPathLengthSampling() ) {
+ // t is upper bound on path (arc) length
+ REAL d = mapdesc->calcPartialVelocity( &tmp[0][0], tstride, order, 1, range[2] );
+ stepsize = ( d > 0.0 ) ? (t / d) : range[2];
+ minstepsize = ( mapdesc->maxrate > 0.0 ) ? (range[2] / mapdesc->maxrate) : 0.0;
+ } else {
+ // control points cross infinity, therefore partials are undefined
+ setstepsize( mapdesc->maxrate );
+ }
+ }
+ }
+}
+
+int
+Curve::needsSamplingSubdivision( void )
+{
+ return ( stepsize < minstepsize ) ? 1 : 0;
+}
+
+int
+Curve::cullCheck( void )
+{
+ if( cullval == CULL_ACCEPT )
+ cullval = mapdesc->cullCheck( cpts, order, stride );
+ return cullval;
+}
+