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Retrieves the coordinates of a projection in the projection plane, given the parallelogram coordinates of a point (for use with selected TDPACK routines).

Available in version 4.3.1 and later.


	function tdprpa (
		xyipa [2] : float   

	return_val [2] :  float



A float array of 2 elements defining the parallelogram coordinates of a point.

Return value

A float array of two elements containing the coordinates of the projection of the point in the projection plane.


This function is part of the low-level TDPACK package, which is a group of Fortran and C callable routines for projecting objects from a 3-dimensional coordinate system having U, V, and W axes to a 2-dimensional projection plane having X and Y axes and/or for drawing the projections of those objects. This can be referred to somewhat loosely as "drawing objects in three dimensions".

Please see the documentation on TDPRPA for a full description of this function.

See Also

Initialization routines: tdinit, tdpara, tdclrs

Parameter access routines: tdgetp, tdgtrs, tdsetp, tdstrs

Point transforming routines: tdprpt, tdprpi

Line drawing routines: tdline, tdlndp, tdlnpa, tdlpdp, tdcurv, tdcudp

Grid drawing routines: tdgrds, tdgrid

Label drawing routines: tdlbls, tdlbla, tdlblp, tdplch

Surface drawing routines: tddtri, tdstri, tditri, tdmtri, tdttri, tdctri, tdotri, tdsort

Simplified interface routines: tdez2d, tdez3d


No examples are currently available for this function. Please see the documentation on TDPRPA for more information about this function.