# SETTRANSFORM

**//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