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Diffstat (limited to 'mesalib/src/glu/sgi/libnurbs/internals/curvesub.cc')
| -rw-r--r-- | mesalib/src/glu/sgi/libnurbs/internals/curvesub.cc | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/mesalib/src/glu/sgi/libnurbs/internals/curvesub.cc b/mesalib/src/glu/sgi/libnurbs/internals/curvesub.cc new file mode 100644 index 000000000..f85acc269 --- /dev/null +++ b/mesalib/src/glu/sgi/libnurbs/internals/curvesub.cc @@ -0,0 +1,103 @@ +/* +** 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. +*/ + +/* + * curvesub.c++ + * + */ + +#include "glimports.h" +#include "myassert.h" +#include "mystdio.h" +#include "subdivider.h" +#include "renderhints.h" +#include "backend.h" +#include "quilt.h" +#include "curvelist.h" +#include "curve.h" +#include "nurbsconsts.h" + +/*-------------------------------------------------------------------------- + * drawCurves - main curve rendering entry point + *-------------------------------------------------------------------------- + */ + +void +Subdivider::drawCurves( void ) +{ + REAL from[1], to[1]; + Flist bpts; + qlist->getRange( from, to, bpts ); + + renderhints.init( ); + + backend.bgncurv(); + for( int i=bpts.start; i<bpts.end-1; i++ ) { + REAL pta, ptb; + pta = bpts.pts[i]; + ptb = bpts.pts[i+1]; + + qlist->downloadAll( &pta, &ptb, backend ); + + Curvelist curvelist( qlist, pta, ptb ); + samplingSplit( curvelist, renderhints.maxsubdivisions ); + } + backend.endcurv(); +} + + +/*-------------------------------------------------------------------------- + * samplingSplit - recursively subdivide patch, cull check each subpatch + *-------------------------------------------------------------------------- + */ + +void +Subdivider::samplingSplit( Curvelist& curvelist, int subdivisions ) +{ + if( curvelist.cullCheck() == CULL_TRIVIAL_REJECT ) return; + + curvelist.getstepsize(); + + if( curvelist.needsSamplingSubdivision() && (subdivisions > 0) ) { + REAL mid = ( curvelist.range[0] + curvelist.range[1] ) * 0.5; + Curvelist lowerlist( curvelist, mid ); + samplingSplit( lowerlist, subdivisions-1 ); // lower + samplingSplit( curvelist, subdivisions-1 ); // upper + } else { + long nu = 1 + ((long) (curvelist.range[2] / curvelist.stepsize)); + backend.curvgrid( curvelist.range[0], curvelist.range[1], nu ); + backend.curvmesh( 0, nu ); + } +} + |