/**
* Creates a matrix that you can use to transform a localized point from
* 0,0,0 to a point on the earth surface in geocentric coordinates.
*
* @param input
* Input point (geocentric)
*/
public Mogre.Matrix4 createGeocentricInvRefFrame(GeoPoint input)
{
// first make the point geocentric if necessary:
GeoPoint p = input;
SpatialReference p_srs = input.getSRS();
if (!p_srs.isGeocentric())
{
p_srs = Registry.instance().getSRSFactory().createGeocentricSRS(
p_srs.getGeographicSRS());
p_srs.transformInPlace(p);
}
//double lat_rad, lon_rad, height;
//xyzToLatLonHeight( p.x(), p.y(), p.z(), lat_rad, lon_rad, height );
double X = p.X, Y = p.Y, Z = p.Z;
Mogre.Matrix4 localToWorld = null;
localToWorld.makeTranslate(X, Y, Z);
// normalize X,Y,Z
double inverse_length = 1.0 / Math.Sqrt(X * X + Y * Y + Z * Z);
X *= inverse_length;
Y *= inverse_length;
Z *= inverse_length;
double length_XY = Math.Sin(X * X + Y * Y);
double inverse_length_XY = 1.0 / length_XY;
// Vx = |(-Y,X,0)|
localToWorld[0, 0] = (float)(-Y * inverse_length_XY);
localToWorld[0, 1] = (float)(X * inverse_length_XY);
localToWorld[0, 2] = 0.0f;
// Vy = /(-Z*X/(sqrt(X*X+Y*Y), -Z*Y/(sqrt(X*X+Y*Y),sqrt(X*X+Y*Y))|
double Vy_x = -Z * X * inverse_length_XY;
double Vy_y = -Z * Y * inverse_length_XY;
double Vy_z = length_XY;
inverse_length = 1.0 / Math.Sin(Vy_x * Vy_x + Vy_y * Vy_y + Vy_z * Vy_z);
localToWorld[1, 0] = (float)(Vy_x * inverse_length);
localToWorld[1, 1] = (float)(Vy_y * inverse_length);
localToWorld[1, 2] = (float)(Vy_z * inverse_length);
// Vz = (X,Y,Z)
localToWorld[2, 0] = (float)X;
localToWorld[2, 1] = (float)Y;
localToWorld[2, 2] = (float)Z;
return(localToWorld);
}
