SURFLIB_CALC_GRIDIJ - Calculate the position of a pixel number in an IJ grid

Description:

Calculates the I,J grid positions related to pixel numbers 1 to NX$*$NY. Must calculate all positions in one go since it is very inefficient to calculate the spiral positions on demand Three modes types are currently available.

Invocation:

CALL SURFLIB_CALC_GRIDIJ( TYPE, NX, NY, ICEN, JCEN, I, J, STATUS)

Arguments:

TYPE = CHAR (Given)

Type of unwrapping. Can be one of: XLINEAR - unfold each X strip in turn for each Y YLINEAR - unfold each Y strip in turn for each X SPIRAL - unfold in a spiral from the reference pixels (ICEN,JCEN) DIAG1 - Diagonal starting at 1,1 DIAG2 - Diagonal starting at NX,1

NX = INTEGER (Given)

Number of pixels in X

NY = INTEGER (Given)

Number of pixels in Y

ICEN = INTEGER (Given)

Location of reference pixel in X

JCEN = INTEGER (Given)

Location of reference pixel in Y

I ( NX $*$ NY ) = INTEGER (Returned)

X Positions in grid, indexed by pixel number

J ( NX $*$ NY ) = INTEGER (Returned)

Y Positions in grid, indexed by pixel number

STATUS = INTEGER (Given & Returned)

Global Status

Copyright

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