| /* |
| ** 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. |
| */ |
| |
| /* |
| * trimline.c++ |
| * |
| * $Date: 2012/03/29 17:22:17 $ $Revision: 1.1.1.1 $ |
| * $Header: /cvs/bao-parsec/pkgs/libs/mesa/src/src/glu/sgi/libnurbs/internals/trimline.cc,v 1.1.1.1 2012/03/29 17:22:17 uid42307 Exp $ |
| */ |
| |
| #include "glimports.h" |
| #include "myassert.h" |
| #include "mystdio.h" |
| #include "trimline.h" |
| #include "backend.h" |
| |
| Trimline::Trimline() |
| { |
| size = 0; pts = 0; numverts = 0; |
| tinterp = &t; binterp = &b; |
| } |
| |
| Trimline::~Trimline() |
| { |
| if( pts ) delete[] pts; |
| } |
| |
| void |
| Trimline::init( TrimVertex *v ) |
| { |
| reset(); |
| grow(1); |
| append(v); |
| } |
| |
| inline void |
| Trimline::grow( long npts ) |
| { |
| if( size < npts ) { |
| size = 2 * npts; |
| if( pts ) delete[] pts; |
| pts = new TrimVertex_p[size]; |
| } |
| } |
| |
| inline void |
| Trimline::append( TrimVertex *v ) |
| { |
| assert( numverts != size ); |
| pts[numverts++] = v; |
| } |
| |
| void |
| Trimline::init( long npts, Arc_ptr jarc, long last ) |
| { |
| jarcl.init( jarc, 0, last ); |
| grow( npts + 2 ); |
| } |
| |
| inline void |
| Trimline::swap() |
| { |
| TrimVertex *tmp=tinterp; |
| tinterp=binterp; |
| binterp=tmp; |
| } |
| |
| void |
| Trimline::getNextPt() |
| { |
| *binterp = *jarcl.getnextpt(); |
| } |
| |
| void |
| Trimline::getPrevPt() |
| { |
| *binterp = *jarcl.getprevpt(); |
| } |
| |
| /*---------------------------------------------------------------------- |
| * getNextPts - make arrays of pointers to trim points on left and right |
| * hulls of trim strip. |
| *---------------------------------------------------------------------- |
| */ |
| void |
| Trimline::getNextPts( REAL vval, Backend& backend ) |
| { |
| reset(); swap(); append( tinterp ); |
| assert( tinterp->param[1] >= vval ); |
| |
| register TrimVertex *p; |
| for( p=jarcl.getnextpt() ; p->param[1] >= vval; p=jarcl.getnextpt() ) { |
| append( p ); |
| } |
| |
| /* compute and copy pointer to final point on left hull */ |
| if( interpvert( last(), p, binterp, vval ) ) { |
| binterp->nuid = p->nuid; |
| backend.triangle( p, binterp, last() ); |
| append( binterp ); |
| } |
| jarcl.reverse(); |
| (void) jarcl.getprevpt(); /* reset jarcl to proper position */ |
| jarcl.reverse(); |
| } |
| |
| void |
| Trimline::getPrevPts( REAL vval, Backend& backend ) |
| { |
| reset(); swap(); append( tinterp ); |
| assert( tinterp->param[1] >= vval ); |
| |
| register TrimVertex *q; |
| for( q=jarcl.getprevpt(); q->param[1] >= vval; q=jarcl.getprevpt() ) { |
| append( q ); |
| } |
| |
| /* compute and copy pointer to final point on right hull */ |
| if( interpvert( q, last(), binterp, vval ) ) { |
| binterp->nuid = q->nuid; |
| backend.triangle( last(), binterp, q ); |
| append( binterp ); |
| } |
| jarcl.reverse(); |
| (void) jarcl.getnextpt(); /* reset jarcl to proper position */ |
| jarcl.reverse(); |
| } |
| |
| void |
| Trimline::getNextPts( Arc_ptr botarc ) |
| { |
| reset(); swap(); append( tinterp ); |
| |
| #ifndef NDEBUG |
| PwlArc *lastpwl = botarc->prev->pwlArc; |
| TrimVertex *lastpt1 = &lastpwl->pts[lastpwl->npts-1]; |
| #endif |
| TrimVertex *lastpt2 = botarc->pwlArc->pts; |
| register TrimVertex *p = jarcl.getnextpt(); |
| for( append( p ); p != lastpt2; append( p ) ) { |
| assert( p != lastpt1 ); |
| p = jarcl.getnextpt(); |
| } |
| } |
| |
| void |
| Trimline::getPrevPts( Arc_ptr botarc ) |
| { |
| reset(); swap(); append( tinterp ); |
| |
| PwlArc *lastpwl = botarc->prev->pwlArc; |
| TrimVertex *lastpt1 = &lastpwl->pts[lastpwl->npts-1]; |
| #ifndef NDEBUG |
| TrimVertex *lastpt2 = botarc->pwlArc->pts; |
| #endif |
| |
| register TrimVertex *q = jarcl.getprevpt(); |
| for( append( q ); q != lastpt1; append( q ) ) { |
| assert( q != lastpt2 ); |
| q = jarcl.getprevpt(); |
| } |
| } |
| |
| |
| long |
| Trimline::interpvert( TrimVertex *a, TrimVertex *b, TrimVertex *c, REAL vval ) |
| { |
| REAL denom = a->param[1] - b->param[1]; |
| |
| if(denom != 0) { |
| if( vval == a->param[1] ) { |
| c->param[0] = a->param[0]; |
| c->param[1] = a->param[1]; |
| c->nuid = a->nuid; |
| return 0; |
| } else if( vval == b->param[1] ) { |
| c->param[0] = b->param[0]; |
| c->param[1] = b->param[1]; |
| c->nuid = b->nuid; |
| return 0; |
| } else { |
| REAL r = (a->param[1] - vval)/denom; |
| c->param[0] = a->param[0] - r * (a->param[0] - b->param[0]); |
| c->param[1] = vval; |
| return 1; |
| } |
| } else { |
| c->param[0] = a->param[0]; |
| c->param[1] = a->param[1]; |
| c->nuid = a->nuid; |
| return 0; |
| } |
| } |
| |