| /* |
| ** 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: 2012/03/29 17:22:17 $ $Revision: 1.1.1.1 $ |
| * $Header: /cvs/bao-parsec/pkgs/libs/mesa/src/src/glu/sgi/libnurbs/internals/varray.cc,v 1.1.1.1 2012/03/29 17:22:17 uid42307 Exp $ |
| */ |
| |
| #include "glimports.h" |
| #include "myassert.h" |
| #include "mystdio.h" |
| #include "varray.h" |
| #include "arc.h" |
| #include "simplemath.h" // glu_abs() |
| |
| #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( glu_abs(left->tail()[1] - botarc->tail()[1]) < TINY) goto end; |
| if( glu_abs(left->tail()[0]-right->prev->tail()[0]) < TINY && |
| glu_abs(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; |
| } |
| |