SEuler * seuler_trans_zxz ( SEuler * out , const SEuler * in , const SEuler * se )
{
static SPoint sp[4] ;
sp[0].lng = 0.0;
sp[0].lat = 0.0;
sp[1].lng = PIH;
sp[1].lat = 0.0;
euler_spoint_trans ( &sp[2], &sp[0], in );
euler_spoint_trans ( &sp[3], &sp[1], in );
euler_spoint_trans ( &sp[0], &sp[2], se );
euler_spoint_trans ( &sp[1], &sp[3], se );
spherevector_to_euler ( out , &sp[0], &sp[1] );
return out;
}
/*
* 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;
}
Datum spheretrans_point(PG_FUNCTION_ARGS)
{
SPoint * sp = ( SPoint * ) PG_GETARG_POINTER ( 0 ) ;
SEuler * se = ( SEuler * ) PG_GETARG_POINTER ( 1 ) ;
SPoint * out = ( SPoint * ) MALLOC ( sizeof ( SPoint ) );
PG_RETURN_POINTER ( euler_spoint_trans ( out , sp , se ) );
}
bool strans_eq ( const SEuler * e1, const SEuler * e2 )
{
static SPoint in[2], p[4] ;
in[0].lng = 0.0;
in[0].lat = 0.0;
in[1].lng = PIH;
in[1].lat = 0.0;
euler_spoint_trans ( &p[0] , &in[0] , e1 );
euler_spoint_trans ( &p[1] , &in[1] , e1 );
euler_spoint_trans ( &p[2] , &in[0] , e2 );
euler_spoint_trans ( &p[3] , &in[1] , e2 );
return ( spoint_eq ( &p[0], &p[2] ) && spoint_eq ( &p[1], &p[3] ) );
}
Datum spherepoly_area(PG_FUNCTION_ARGS)
{
SPOLY * poly = PG_GETARG_SPOLY( 0 ) ;
int32 i;
SPoint s[poly->npts + 2];
SPoint stmp[2];
SEuler se;
float8 sum = 0.0;
memcpy( (void*)&s[1], (void*)&poly->p[0] , poly->npts * sizeof( SPoint ) );
memcpy( (void*)&s[0], (void*)&s[poly->npts] , sizeof( SPoint ) );
memcpy( (void*)&s[poly->npts+1], (void*)&s[1] , sizeof( SPoint ) );
se.psi = 0;
se.phi_a = EULER_AXIS_Z;
se.theta_a = EULER_AXIS_X;
se.psi_a = EULER_AXIS_Z;
for ( i=1; i<=poly->npts; i++ ){
se.phi = -PIH - s[i].lng ;
se.theta = s[i].lat - PIH ;
euler_spoint_trans( &stmp[0] , &s[i-1] , &se );
euler_spoint_trans( &stmp[1] , &s[i+1] , &se );
stmp[1].lng -= stmp[0].lng;
if ( FPlt(stmp[1].lng,0.0) ){
stmp[1].lng += PID;
}
sum += stmp[1].lng ;
}
sum -= ( PI * ( poly->npts - 2 ) ) ;
if ( FPge(sum,PID) ){
sum = 2*PID - sum;
}
if ( FPzero(sum) ){
sum = 0.0;
}
PG_RETURN_FLOAT8 ( sum );
}
/*!
\brief Does a transformation of polygon using Euler transformation
\param se pointer to Euler transformation
\param in pointer to polygon
\param out pointer to transformed polygon
\return pointer to transformed polygon
*/
static SPOLY * euler_spoly_trans ( SPOLY * out , const SPOLY * in , const SEuler * se )
{
int32 i;
out->size = in->size;
out->npts = in->npts;
for ( i=0; i<in->npts ; i++ ){
euler_spoint_trans ( &out->p[i] , &in->p[i] , se );
}
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 ;
}
SCIRCLE * euler_scircle_trans ( SCIRCLE * out , const SCIRCLE * in , const SEuler * se )
{
euler_spoint_trans ( &out->center , &in->center , se );
out->radius = in->radius;
return out;
}