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authormarha <marha@users.sourceforge.net>2009-10-08 13:15:52 +0000
committermarha <marha@users.sourceforge.net>2009-10-08 13:15:52 +0000
commita0c4815433ccd57322f4f7703ca35e9ccfa59250 (patch)
treef5213802ec12adb86ec3136001c1c29fe5343700 /mesalib/src/glu/sgi/libnurbs/internals/arctess.cc
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Added MesaLib-7.6
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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.
+*/
+
+/*
+ * arctessellator.c++
+ *
+ */
+
+#include "glimports.h"
+#include "mystdio.h"
+#include "myassert.h"
+#include "arctess.h"
+#include "bufpool.h"
+#include "simplemath.h"
+#include "bezierarc.h"
+#include "trimvertex.h"
+#include "trimvertpool.h"
+
+#define NOELIMINATION
+
+#define steps_function(large, small, rate) (max(1, 1+ (int) ((large-small)/rate)));
+
+/*-----------------------------------------------------------------------------
+ * ArcTessellator - construct an ArcTessellator
+ *-----------------------------------------------------------------------------
+ */
+
+ArcTessellator::ArcTessellator( TrimVertexPool& t, Pool& p )
+ : pwlarcpool(p), trimvertexpool(t)
+{
+}
+
+/*-----------------------------------------------------------------------------
+ * ~ArcTessellator - destroy an ArcTessellator
+ *-----------------------------------------------------------------------------
+ */
+
+ArcTessellator::~ArcTessellator( void )
+{
+}
+
+/*-----------------------------------------------------------------------------
+ * bezier - construct a bezier arc and attach it to an Arc
+ *-----------------------------------------------------------------------------
+ */
+
+void
+ArcTessellator::bezier( Arc *arc, REAL s1, REAL s2, REAL t1, REAL t2 )
+{
+ assert( arc != 0 );
+ assert( ! arc->isTessellated() );
+
+#ifndef NDEBUG
+ switch( arc->getside() ) {
+ case arc_left:
+ assert( s1 == s2 );
+ assert( t2 < t1 );
+ break;
+ case arc_right:
+ assert( s1 == s2 );
+ assert( t1 < t2 );
+ break;
+ case arc_top:
+ assert( t1 == t2 );
+ assert( s2 < s1 );
+ break;
+ case arc_bottom:
+ assert( t1 == t2 );
+ assert( s1 < s2 );
+ break;
+ case arc_none:
+ (void) abort();
+ break;
+ }
+#endif
+
+ TrimVertex *p = trimvertexpool.get(2);
+ arc->pwlArc = new(pwlarcpool) PwlArc( 2, p );
+ p[0].param[0] = s1;
+ p[0].param[1] = t1;
+ p[1].param[0] = s2;
+ p[1].param[1] = t2;
+ assert( (s1 == s2) || (t1 == t2) );
+ arc->setbezier();
+}
+
+
+/*-----------------------------------------------------------------------------
+ * pwl_left - construct a left boundary pwl arc and attach it to an arc
+ *-----------------------------------------------------------------------------
+ */
+
+void
+ArcTessellator::pwl_left( Arc *arc, REAL s, REAL t1, REAL t2, REAL rate )
+{
+ assert( t2 < t1 );
+
+/* if(rate <= 0.06) rate = 0.06;*/
+/* int nsteps = 1 + (int) ((t1 - t2) / rate ); */
+ int nsteps = steps_function(t1, t2, rate);
+
+
+ REAL stepsize = (t1 - t2) / (REAL) nsteps;
+
+ TrimVertex *newvert = trimvertexpool.get( nsteps+1 );
+ int i;
+ for( i = nsteps; i > 0; i-- ) {
+ newvert[i].param[0] = s;
+ newvert[i].param[1] = t2;
+ t2 += stepsize;
+ }
+ newvert[i].param[0] = s;
+ newvert[i].param[1] = t1;
+
+ arc->makeSide( new(pwlarcpool) PwlArc( nsteps+1, newvert ), arc_left );
+}
+
+/*-----------------------------------------------------------------------------
+ * pwl_right - construct a right boundary pwl arc and attach it to an arc
+ *-----------------------------------------------------------------------------
+ */
+
+void
+ArcTessellator::pwl_right( Arc *arc, REAL s, REAL t1, REAL t2, REAL rate )
+{
+ assert( t1 < t2 );
+
+/* if(rate <= 0.06) rate = 0.06;*/
+
+/* int nsteps = 1 + (int) ((t2 - t1) / rate ); */
+ int nsteps = steps_function(t2,t1,rate);
+ REAL stepsize = (t2 - t1) / (REAL) nsteps;
+
+ TrimVertex *newvert = trimvertexpool.get( nsteps+1 );
+ int i;
+ for( i = 0; i < nsteps; i++ ) {
+ newvert[i].param[0] = s;
+ newvert[i].param[1] = t1;
+ t1 += stepsize;
+ }
+ newvert[i].param[0] = s;
+ newvert[i].param[1] = t2;
+
+ arc->makeSide( new(pwlarcpool) PwlArc( nsteps+1, newvert ), arc_right );
+}
+
+
+/*-----------------------------------------------------------------------------
+ * pwl_top - construct a top boundary pwl arc and attach it to an arc
+ *-----------------------------------------------------------------------------
+ */
+
+void
+ArcTessellator::pwl_top( Arc *arc, REAL t, REAL s1, REAL s2, REAL rate )
+{
+ assert( s2 < s1 );
+
+/* if(rate <= 0.06) rate = 0.06;*/
+
+/* int nsteps = 1 + (int) ((s1 - s2) / rate ); */
+ int nsteps = steps_function(s1,s2,rate);
+ REAL stepsize = (s1 - s2) / (REAL) nsteps;
+
+ TrimVertex *newvert = trimvertexpool.get( nsteps+1 );
+ int i;
+ for( i = nsteps; i > 0; i-- ) {
+ newvert[i].param[0] = s2;
+ newvert[i].param[1] = t;
+ s2 += stepsize;
+ }
+ newvert[i].param[0] = s1;
+ newvert[i].param[1] = t;
+
+ arc->makeSide( new(pwlarcpool) PwlArc( nsteps+1, newvert ), arc_top );
+}
+
+/*-----------------------------------------------------------------------------
+ * pwl_bottom - construct a bottom boundary pwl arc and attach it to an arc
+ *-----------------------------------------------------------------------------
+ */
+
+void
+ArcTessellator::pwl_bottom( Arc *arc, REAL t, REAL s1, REAL s2, REAL rate )
+{
+ assert( s1 < s2 );
+
+/* if(rate <= 0.06) rate = 0.06;*/
+
+/* int nsteps = 1 + (int) ((s2 - s1) / rate ); */
+ int nsteps = steps_function(s2,s1,rate);
+ REAL stepsize = (s2 - s1) / (REAL) nsteps;
+
+ TrimVertex *newvert = trimvertexpool.get( nsteps+1 );
+ int i;
+ for( i = 0; i < nsteps; i++ ) {
+ newvert[i].param[0] = s1;
+ newvert[i].param[1] = t;
+ s1 += stepsize;
+ }
+ newvert[i].param[0] = s2;
+ newvert[i].param[1] = t;
+
+ arc->makeSide( new(pwlarcpool) PwlArc( nsteps+1, newvert ), arc_bottom );
+}
+
+/*-----------------------------------------------------------------------------
+ * pwl - construct a pwl arc and attach it to an arc
+ *-----------------------------------------------------------------------------
+ */
+
+void
+ArcTessellator::pwl( Arc *arc, REAL s1, REAL s2, REAL t1, REAL t2, REAL rate )
+{
+
+/* if(rate <= 0.06) rate = 0.06;*/
+
+ int snsteps = 1 + (int) (glu_abs(s2 - s1) / rate );
+ int tnsteps = 1 + (int) (glu_abs(t2 - t1) / rate );
+ int nsteps = max(1,max( snsteps, tnsteps ));
+
+ REAL sstepsize = (s2 - s1) / (REAL) nsteps;
+ REAL tstepsize = (t2 - t1) / (REAL) nsteps;
+ TrimVertex *newvert = trimvertexpool.get( nsteps+1 );
+ long i;
+ for( i = 0; i < nsteps; i++ ) {
+ newvert[i].param[0] = s1;
+ newvert[i].param[1] = t1;
+ s1 += sstepsize;
+ t1 += tstepsize;
+ }
+ newvert[i].param[0] = s2;
+ newvert[i].param[1] = t2;
+
+ /* arc->makeSide( new(pwlarcpool) PwlArc( nsteps+1, newvert ), arc_bottom ); */
+ arc->pwlArc = new(pwlarcpool) PwlArc( nsteps+1, newvert );
+
+ arc->clearbezier();
+ arc->clearside( );
+}
+
+
+/*-----------------------------------------------------------------------------
+ * tessellateLinear - constuct a linear pwl arc and attach it to an Arc
+ *-----------------------------------------------------------------------------
+ */
+
+void
+ArcTessellator::tessellateLinear( Arc *arc, REAL geo_stepsize, REAL arc_stepsize, int isrational )
+{
+ assert( arc->pwlArc == NULL );
+ REAL s1, s2, t1, t2;
+
+ //we don't need to scale by arc_stepsize if the trim curve
+ //is piecewise linear. Reason: In pwl_right, pwl_left, pwl_top, pwl_left,
+ //and pwl, the nsteps is computed by deltaU (or V) /stepsize.
+ //The quantity deltaU/arc_stepsize doesn't have any meaning. And
+ //it causes problems: see bug 517641
+ REAL stepsize = geo_stepsize; /* * arc_stepsize*/;
+
+ BezierArc *b = arc->bezierArc;
+
+ if( isrational ) {
+ s1 = b->cpts[0] / b->cpts[2];
+ t1 = b->cpts[1] / b->cpts[2];
+ s2 = b->cpts[b->stride+0] / b->cpts[b->stride+2];
+ t2 = b->cpts[b->stride+1] / b->cpts[b->stride+2];
+ } else {
+ s1 = b->cpts[0];
+ t1 = b->cpts[1];
+ s2 = b->cpts[b->stride+0];
+ t2 = b->cpts[b->stride+1];
+ }
+ if( s1 == s2 )
+ if( t1 < t2 )
+ pwl_right( arc, s1, t1, t2, stepsize );
+ else
+ pwl_left( arc, s1, t1, t2, stepsize );
+ else if( t1 == t2 )
+ if( s1 < s2 )
+ pwl_bottom( arc, t1, s1, s2, stepsize );
+ else
+ pwl_top( arc, t1, s1, s2, stepsize );
+ else
+ pwl( arc, s1, s2, t1, t2, stepsize );
+}
+
+/*-----------------------------------------------------------------------------
+ * tessellateNonlinear - constuct a nonlinear pwl arc and attach it to an Arc
+ *-----------------------------------------------------------------------------
+ */
+
+void
+ArcTessellator::tessellateNonlinear( Arc *arc, REAL geo_stepsize, REAL arc_stepsize, int isrational )
+{
+ assert( arc->pwlArc == NULL );
+
+ REAL stepsize = geo_stepsize * arc_stepsize;
+
+ BezierArc *bezierArc = arc->bezierArc;
+
+ REAL size; //bounding box size of the curve in UV
+ {
+ int i,j;
+ REAL min_u, min_v, max_u,max_v;
+ min_u = max_u = bezierArc->cpts[0];
+ min_v = max_v = bezierArc->cpts[1];
+ for(i=1, j=bezierArc->stride; i<bezierArc->order; i++, j+= bezierArc->stride)
+ {
+ if(bezierArc->cpts[j] < min_u)
+ min_u = bezierArc->cpts[j];
+ if(bezierArc->cpts[j] > max_u)
+ max_u = bezierArc->cpts[j];
+ if(bezierArc->cpts[j+1] < min_v)
+ min_v = bezierArc->cpts[j+1];
+ if(bezierArc->cpts[j+1] > max_v)
+ max_v = bezierArc->cpts[j+1];
+ }
+
+ size = max_u - min_u;
+ if(size < max_v - min_v)
+ size = max_v - min_v;
+ }
+
+ /*int nsteps = 1 + (int) (1.0/stepsize);*/
+
+ int nsteps = (int) (size/stepsize);
+ if(nsteps <=0)
+ nsteps=1;
+
+ TrimVertex *vert = trimvertexpool.get( nsteps+1 );
+ REAL dp = 1.0/nsteps;
+
+
+ arc->pwlArc = new(pwlarcpool) PwlArc();
+ arc->pwlArc->pts = vert;
+
+ if( isrational ) {
+ REAL pow_u[MAXORDER], pow_v[MAXORDER], pow_w[MAXORDER];
+ trim_power_coeffs( bezierArc, pow_u, 0 );
+ trim_power_coeffs( bezierArc, pow_v, 1 );
+ trim_power_coeffs( bezierArc, pow_w, 2 );
+
+ /* compute first point exactly */
+ REAL *b = bezierArc->cpts;
+ vert->param[0] = b[0]/b[2];
+ vert->param[1] = b[1]/b[2];
+
+ /* strength reduction on p = dp * step would introduce error */
+ int step;
+#ifndef NOELIMINATION
+ int ocanremove = 0;
+#endif
+ register long order = bezierArc->order;
+ for( step=1, ++vert; step<nsteps; step++, vert++ ) {
+ register REAL p = dp * step;
+ register REAL u = pow_u[0];
+ register REAL v = pow_v[0];
+ register REAL w = pow_w[0];
+ for( register int i = 1; i < order; i++ ) {
+ u = u * p + pow_u[i];
+ v = v * p + pow_v[i];
+ w = w * p + pow_w[i];
+ }
+ vert->param[0] = u/w;
+ vert->param[1] = v/w;
+#ifndef NOELIMINATION
+ REAL ds = glu_abs(vert[0].param[0] - vert[-1].param[0]);
+ REAL dt = glu_abs(vert[0].param[1] - vert[-1].param[1]);
+ int canremove = (ds<geo_stepsize && dt<geo_stepsize) ? 1 : 0;
+ REAL ods=0.0, odt=0.0;
+
+ if( ocanremove && canremove ) {
+ REAL nds = ds + ods;
+ REAL ndt = dt + odt;
+ if( nds<geo_stepsize && ndt<geo_stepsize ) {
+ // remove previous point
+ --vert;
+ vert[0].param[0] = vert[1].param[0];
+ vert[0].param[1] = vert[1].param[1];
+ ods = nds;
+ odt = ndt;
+ ocanremove = 1;
+ } else {
+ ocanremove = canremove;
+ ods = ds;
+ odt = dt;
+ }
+ } else {
+ ocanremove = canremove;
+ ods = ds;
+ odt = dt;
+ }
+#endif
+ }
+
+ /* compute last point exactly */
+ b += (order - 1) * bezierArc->stride;
+ vert->param[0] = b[0]/b[2];
+ vert->param[1] = b[1]/b[2];
+
+ } else {
+ REAL pow_u[MAXORDER], pow_v[MAXORDER];
+ trim_power_coeffs( bezierArc, pow_u, 0 );
+ trim_power_coeffs( bezierArc, pow_v, 1 );
+
+ /* compute first point exactly */
+ REAL *b = bezierArc->cpts;
+ vert->param[0] = b[0];
+ vert->param[1] = b[1];
+
+ /* strength reduction on p = dp * step would introduce error */
+ int step;
+#ifndef NOELIMINATION
+ int ocanremove = 0;
+#endif
+ register long order = bezierArc->order;
+ for( step=1, ++vert; step<nsteps; step++, vert++ ) {
+ register REAL p = dp * step;
+ register REAL u = pow_u[0];
+ register REAL v = pow_v[0];
+ for( register int i = 1; i < bezierArc->order; i++ ) {
+ u = u * p + pow_u[i];
+ v = v * p + pow_v[i];
+ }
+ vert->param[0] = u;
+ vert->param[1] = v;
+#ifndef NOELIMINATION
+ REAL ds = glu_abs(vert[0].param[0] - vert[-1].param[0]);
+ REAL dt = glu_abs(vert[0].param[1] - vert[-1].param[1]);
+ int canremove = (ds<geo_stepsize && dt<geo_stepsize) ? 1 : 0;
+ REAL ods=0.0, odt=0.0;
+
+ if( ocanremove && canremove ) {
+ REAL nds = ds + ods;
+ REAL ndt = dt + odt;
+ if( nds<geo_stepsize && ndt<geo_stepsize ) {
+ // remove previous point
+ --vert;
+ vert[0].param[0] = vert[1].param[0];
+ vert[0].param[1] = vert[1].param[1];
+ ods = nds;
+ odt = ndt;
+ ocanremove = 1;
+ } else {
+ ocanremove = canremove;
+ ods = ds;
+ odt = dt;
+ }
+ } else {
+ ocanremove = canremove;
+ ods = ds;
+ odt = dt;
+ }
+#endif
+ }
+
+ /* compute last point exactly */
+ b += (order - 1) * bezierArc->stride;
+ vert->param[0] = b[0];
+ vert->param[1] = b[1];
+ }
+ arc->pwlArc->npts = vert - arc->pwlArc->pts + 1;
+/*
+ for( TrimVertex *vt=pwlArc->pts; vt != vert-1; vt++ ) {
+ if( tooclose( vt[0].param[0], vt[1].param[0] ) )
+ vt[1].param[0] = vt[0].param[0];
+ if( tooclose( vt[0].param[1], vt[1].param[1] ) )
+ vt[1].param[1] = vt[0].param[1];
+ }
+*/
+}
+
+const REAL ArcTessellator::gl_Bernstein[][MAXORDER][MAXORDER] = {
+ {
+ {1, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 }
+ },
+ {
+ {-1, 1, 0, 0, 0, 0, 0, 0 },
+ {1, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 }
+ },
+ {
+ {1, -2, 1, 0, 0, 0, 0, 0 },
+ {-2, 2, 0, 0, 0, 0, 0, 0 },
+ {1, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 }
+ },
+ {
+ {-1, 3, -3, 1, 0, 0, 0, 0 },
+ {3, -6, 3, 0, 0, 0, 0, 0 },
+ {-3, 3, 0, 0, 0, 0, 0, 0 },
+ {1, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 }
+ },
+ {
+ {1, -4, 6, -4, 1, 0, 0, 0 },
+ {-4, 12, -12, 4, 0, 0, 0, 0 },
+ {6, -12, 6, 0, 0, 0, 0, 0 },
+ {-4, 4, 0, 0, 0, 0, 0, 0 },
+ {1, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 }
+ },
+ {
+ {-1, 5, -10, 10, -5, 1, 0, 0 },
+ {5, -20, 30, -20, 5, 0, 0, 0 },
+ {-10, 30, -30, 10, 0, 0, 0, 0 },
+ {10, -20, 10, 0, 0, 0, 0, 0 },
+ {-5, 5, 0, 0, 0, 0, 0, 0 },
+ {1, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 }
+ },
+ {
+ {1, -6, 15, -20, 15, -6, 1, 0 },
+ {-6, 30, -60, 60, -30, 6, 0, 0 },
+ {15, -60, 90, -60, 15, 0, 0, 0 },
+ {-20, 60, -60, 20, 0, 0, 0, 0 },
+ {15, -30, 15, 0, 0, 0, 0, 0 },
+ {-6, 6, 0, 0, 0, 0, 0, 0 },
+ {1, 0, 0, 0, 0, 0, 0, 0 },
+ {0, 0, 0, 0, 0, 0, 0, 0 }
+ },
+ {
+ {-1, 7, -21, 35, -35, 21, -7, 1 },
+ {7, -42, 105, -140, 105, -42, 7, 0 },
+ {-21, 105, -210, 210, -105, 21, 0, 0 },
+ {35, -140, 210, -140, 35, 0, 0, 0 },
+ {-35, 105, -105, 35, 0, 0, 0, 0 },
+ {21, -42, 21, 0, 0, 0, 0, 0 },
+ {-7, 7, 0, 0, 0, 0, 0, 0 },
+ {1, 0, 0, 0, 0, 0, 0, 0 }
+ }};
+
+
+/*-----------------------------------------------------------------------------
+ * trim_power_coeffs - compute power basis coefficients from bezier coeffients
+ *-----------------------------------------------------------------------------
+ */
+void
+ArcTessellator::trim_power_coeffs( BezierArc *bez_arc, REAL *p, int coord )
+{
+ register int stride = bez_arc->stride;
+ register int order = bez_arc->order;
+ register REAL *base = bez_arc->cpts + coord;
+
+ REAL const (*mat)[MAXORDER][MAXORDER] = &gl_Bernstein[order-1];
+ REAL const (*lrow)[MAXORDER] = &(*mat)[order];
+
+ /* WIN32 didn't like the following line within the for-loop */
+ REAL const (*row)[MAXORDER] = &(*mat)[0];
+ for( ; row != lrow; row++ ) {
+ register REAL s = 0.0;
+ register REAL *point = base;
+ register REAL const *mlast = *row + order;
+ for( REAL const *m = *row; m != mlast; m++, point += stride )
+ s += *(m) * (*point);
+ *(p++) = s;
+ }
+}