/*
* Transforms a spherical vector from 'spb' to 'spe' into an inverse Euler
* transformation. Returns true if the transformation was successful.
*/
static bool
spherevector_to_euler_inv(SEuler *se, const SPoint *spb, const SPoint *spe)
{
if (spoint_eq(spb, spe))
{
return false;
}
else
{
Vector3D vbeg, vend, vtmp;
SPoint spt[2];
SEuler set;
spoint_vector3d(&vbeg, spb);
spoint_vector3d(&vend, spe);
vector3d_cross(&vtmp, &vbeg, &vend);
vector3d_spoint(&spt[0], &vtmp);
set.phi = -spt[0].lng - PIH;
set.theta = spt[0].lat - PIH;
set.psi = 0.0;
seuler_set_zxz(&set);
euler_spoint_trans(&spt[1], spb, &set);
set.psi = -spt[1].lng;
memcpy((void *) se, (void *) &set, sizeof(SEuler));
}
return true;
}
SPoint * euler_spoint_trans ( SPoint * out , const SPoint * in , const SEuler * se )
{
Vector3D v,o ;
spoint_vector3d ( &v , in );
euler_vector_trans ( &o , &v , se );
vector3d_spoint ( out , &o );
return out;
}
/*!
\brief Checks crossing of line segments
\param poly pointer to polygon
\return true if crossing
*/
static bool spherepoly_check ( const SPOLY * poly )
{
int32 i, k ;
SLine sli, slk;
Vector3D v ;
SPoint p;
SEuler se;
int8 pos;
spherepoly_center ( &v , poly );
// If 0-vector
if ( FPzero(v.x) && FPzero(v.y) && FPzero(v.z) ){
return FALSE;
}
for ( i=0; i<poly->npts; i++ ){
spoly_segment ( &sli , poly , i );
for ( k=(i+1); k<poly->npts; k++ ){
spoly_segment ( &slk , poly , k );
pos = sline_sline_pos( &sli, &slk );
if ( ! ( pos == PGS_LINE_CONNECT || pos == PGS_LINE_AVOID ) ) {
return FALSE;
}
}
}
vector3d_spoint ( &p , &v );
se.phi_a = EULER_AXIS_Z ;
se.theta_a = EULER_AXIS_X ;
se.psi_a = EULER_AXIS_Z ;
se.phi = -PIH - p.lng ;
se.theta = p.lat - PIH ;
se.psi = 0.0 ;
for ( i=0; i<poly->npts; i++ ){
euler_spoint_trans ( &p , &poly->p[i], &se );
// less _and_ equal are important !!
// Do not change it!
if ( FPle(p.lat,0.0) ) {
return FALSE;
}
}
return TRUE ;
}
