Windows2003-3790/multimedia/opengl/glu/nurbs/core/arc.cxx
2020-09-30 16:53:55 +02:00

333 lines
8.7 KiB
C++

/**************************************************************************
* *
* Copyright (C) 1992, Silicon Graphics, Inc. *
* *
* These coded instructions, statements, and computer programs contain *
* unpublished proprietary information of Silicon Graphics, Inc., and *
* are protected by Federal copyright law. They may not be disclosed *
* to third parties or copied or duplicated in any form, in whole or *
* in part, without the prior written consent of Silicon Graphics, Inc. *
* *
**************************************************************************/
/*
* arc.c++ - $Revision: 1.7 $
* Derrick Burns - 1991
*/
#include "glimport.h"
#include "mystdio.h"
#include "myassert.h"
#include "arc.h"
#include "bin.h"
#include "bezierar.h"
#include "pwlarc.h"
#include "simplema.h"
/* local preprocessor definitions */
#define ZERO 0.00001/*0.000001*/
const int Arc::bezier_tag = (1<<13);
const int Arc::arc_tag = (1<<3);
const int Arc::tail_tag = (1<<6);
/*--------------------------------------------------------------------------
* makeSide - attach a pwl arc to an arc and mark it as a border arc
*--------------------------------------------------------------------------
*/
void
Arc::makeSide( PwlArc *pwl, arc_side side )
{
assert( pwl != 0);
assert( pwlArc == 0 );
assert( pwl->npts > 0 );
assert( pwl->pts != 0);
pwlArc = pwl;
clearbezier();
setside( side );
}
/*--------------------------------------------------------------------------
* numpts - count number of points on arc loop
*--------------------------------------------------------------------------
*/
int
Arc::numpts( void )
{
Arc_ptr jarc = this;
int npts = 0;
do {
npts += jarc->pwlArc->npts;
jarc = jarc->next;
} while( jarc != this );
return npts;
}
/*--------------------------------------------------------------------------
* markverts - mark each point with id of arc
*--------------------------------------------------------------------------
*/
void
Arc::markverts( void )
{
Arc_ptr jarc = this;
do {
TrimVertex *p = jarc->pwlArc->pts;
for( int i=0; i<jarc->pwlArc->npts; i++ )
p[i].nuid = jarc->nuid;
jarc = jarc->next;
} while( jarc != this );
}
/*--------------------------------------------------------------------------
* getextrema - find axis extrema on arc loop
*--------------------------------------------------------------------------
*/
void
Arc::getextrema( Arc_ptr extrema[4] )
{
REAL leftpt, botpt, rightpt, toppt;
extrema[0] = extrema[1] = extrema[2] = extrema[3] = this;
leftpt = rightpt = this->tail()[0];
botpt = toppt = this->tail()[1];
for( Arc_ptr jarc = this->next; jarc != this; jarc = jarc->next ) {
if ( jarc->tail()[0] < leftpt ||
(jarc->tail()[0] <= leftpt && jarc->rhead()[0]<=leftpt)) {
leftpt = jarc->pwlArc->pts->param[0];
extrema[1] = jarc;
}
if ( jarc->tail()[0] > rightpt ||
(jarc->tail()[0] >= rightpt && jarc->rhead()[0] >= rightpt)) {
rightpt = jarc->pwlArc->pts->param[0];
extrema[3] = jarc;
}
if ( jarc->tail()[1] < botpt ||
(jarc->tail()[1] <= botpt && jarc->rhead()[1] <= botpt )) {
botpt = jarc->pwlArc->pts->param[1];
extrema[2] = jarc;
}
if ( jarc->tail()[1] > toppt ||
(jarc->tail()[1] >= toppt && jarc->rhead()[1] >= toppt)) {
toppt = jarc->pwlArc->pts->param[1];
extrema[0] = jarc;
}
}
}
/*-------------------------------------------------------------------------
* show - print to the stdout the vertices of a pwl arc
*-------------------------------------------------------------------------
*/
void
Arc::show()
{
#ifndef NDEBUG
dprintf( "\tPWLARC NP: %d FL: 1\n", pwlArc->npts );
for( int i = 0; i < pwlArc->npts; i++ ) {
dprintf( "\t\tVERTEX %f %f\n", pwlArc->pts[i].param[0],
pwlArc->pts[i].param[1] );
}
#endif
}
/*-------------------------------------------------------------------------
* print - print out the vertices of all pwl arcs on a loop
*-------------------------------------------------------------------------
*/
void
Arc::print( void )
{
Arc_ptr jarc = this;
if( ! this ) {
#ifndef NDEBUG
dprintf( "\n\nEMPTY TRIM\n\n" );
#endif
return;
}
#ifndef NDEBUG
dprintf( "BGNTRIM\n" );
#endif
do {
jarc->show( );
jarc = jarc->next;
} while (jarc != this);
#ifndef NDEBUG
dprintf("ENDTRIM\n" );
#endif
}
/*-------------------------------------------------------------------------
* isDisconnected - check if tail of arc and head of prev meet
*-------------------------------------------------------------------------
*/
int
Arc::isDisconnected( void )
{
if( pwlArc == 0 ) return 0;
if( prev->pwlArc == 0 ) return 0;
REAL *p0 = tail();
REAL *p1 = prev->rhead();
if( ((p0[0] - p1[0]) > ZERO) || ((p1[0] - p0[0]) > ZERO) ||
((p0[1] - p1[1]) > ZERO) || ((p1[1] - p0[1]) > ZERO) ) {
#ifndef NDEBUG
dprintf( "x coord = %f %f %f\n", p0[0], p1[0], p0[0] - p1[0] );
dprintf( "y coord = %f %f %f\n", p0[1], p1[1], p0[1] - p1[1] );
#endif
return 1;
} else {
/* average two points together */
p0[0] = p1[0] = (p1[0] + p0[0]) * 0.5;
p0[1] = p1[1] = (p1[1] + p0[1]) * 0.5;
return 0;
}
}
/*-------------------------------------------------------------------------
* neq_vert - assert that two 2D vertices are not equal
*-------------------------------------------------------------------------
*/
inline static int
neq_vert( REAL *v1, REAL *v2 )
{
return ((v1[0] != v2[0]) || (v1[1] != v2[1] )) ? 1 : 0;
}
/*-------------------------------------------------------------------------
* check - verify consistency of a loop, including
* 1) if pwl, no two consecutive vertices are identical
* 2) the circular link pointers are valid
* 3) the geometric info at the head and tail are consistent
*-------------------------------------------------------------------------
*/
int
Arc::check( void )
{
if( this == 0 ) return 1;
Arc_ptr jarc = this;
do {
assert( (jarc->pwlArc != 0) || (jarc->bezierArc != 0) );
if (jarc->prev == 0 || jarc->next == 0) {
#ifndef NDEBUG
dprintf( "checkjarc:null next/prev pointer\n");
jarc->print( );
#endif
return 0;
}
if (jarc->next->prev != jarc) {
#ifndef NDEBUG
dprintf( "checkjarc: pointer linkage screwed up\n");
jarc->print( );
#endif
return 0;
}
if( jarc->pwlArc ) {
#ifndef NDEBUG
assert( jarc->pwlArc->npts > 1 );
assert( jarc->pwlArc->npts < 100000 );
/*
for( int i=0; i < jarc->pwlArc->npts-1; i++ )
assert( neq_vert( jarc->pwlArc->pts[i].param,
jarc->pwlArc->pts[i+1].param) );
*/
#endif
if( jarc->prev->pwlArc ) {
if( jarc->tail()[1] != jarc->prev->rhead()[1] ) {
#ifndef NDEBUG
dprintf( "checkjarc: geometric linkage screwed up 1\n");
jarc->prev->show();
jarc->show();
#endif
return 0;
}
if( jarc->tail()[0] != jarc->prev->rhead()[0] ) {
#ifndef NDEBUG
dprintf( "checkjarc: geometric linkage screwed up 2\n");
jarc->prev->show();
jarc->show();
#endif
return 0;
}
}
if( jarc->next->pwlArc ) {
if( jarc->next->tail()[0] != jarc->rhead()[0] ) {
#ifndef NDEBUG
dprintf( "checkjarc: geometric linkage screwed up 3\n");
jarc->show();
jarc->next->show();
#endif
return 0;
}
if( jarc->next->tail()[1] != jarc->rhead()[1] ) {
#ifndef NDEBUG
dprintf( "checkjarc: geometric linkage screwed up 4\n");
jarc->show();
jarc->next->show();
#endif
return 0;
}
}
if( jarc->isbezier() ) {
assert( jarc->pwlArc->npts == 2 );
assert( (jarc->pwlArc->pts[0].param[0] == \
jarc->pwlArc->pts[1].param[0]) ||\
(jarc->pwlArc->pts[0].param[1] == \
jarc->pwlArc->pts[1].param[1]) );
}
}
jarc = jarc->next;
} while (jarc != this);
return 1;
}
#define TOL 0.00001
inline long tooclose( REAL x, REAL y )
{
return (abs(x-y) < TOL) ? 1 : 0;
}
/*--------------------------------------------------------------------------
* append - append a jordan arc to a circularly linked list
*--------------------------------------------------------------------------
*/
Arc_ptr
Arc::append( Arc_ptr jarc )
{
if( jarc != 0 ) {
next = jarc->next;
prev = jarc;
next->prev = prev->next = this;
} else {
next = prev = this;
}
return this;
}