Added May 2018

//SETTRANSFORM,m11,m12,m21,m22,dx,dy

where:

m11,m12,m21,m22 are floating point multipliers

dx,dy specify a reference point in twips (1440/inch)

SETTRANSFORM transforms the coordinate space to rotate, translate, shift or stretch the output.

The effect of this operation is to tranform every point (x1,y1) in the original coordinate space to a new point (x2,y2) based on the following formulas:

x2 = (x1 * m11) + (y1 * m21) + dx

y2 = (x1 * m12) + (y1 * m22) + dy

Note that the transformation is independent of SETMAPMODE and affects all subsequent output, with the exception of METAFILE.

Examples

//;mirror about horizontal axis at y=7920 (5.5" down)

//SETTRANSFORM, 1, 0, 0, -1, 0, 15840

//;mirror about vertical axis at x=6120 (4.25"over)

//SETTRANSFORM, -1, 0, 0, 1, 12240, 0

//;rotate 180 around point 4.25" over, 5.5" down (8.5x11 center)

//SETTRANSFORM, -1, 0, 0, -1, 12240, 15840

//;shrink horiz 25%, stretch vert 50%, shift down 1" and right .5"

//SETTRANSFORM, 0.75, 0, 0, 1.5, 720, 1440

History

2018 May, A-Shell 6.5.1635:  Add function to A-Shell