Useful Reference Frame Commands

5.6.2 Useful Reference Frame Commands

[concat] [gsave] [grestore] [rotate] [scale] [translate]

concat

[ a bc d tx ty] concat -

This operator specifies explicity the current transformation matrix. The argument elements a b c d make up the elements of a 2 by 2 matrix. This is the linear transformation part of the affine transformation. The translation is specified by tx and ty for the x and y directions respectively.

gsave

- gsave -

This operator pushes saves a copy of the current graphics state The graphics state consists of (among other things):

gsave is typically used with grestore whenever you need to change the graphics state temporarily and return to the original.

grestore

- grestore -

Sets the current graphics state to the last graphics state saved with gsave.

rotate

angle rotate -

This operator rotates the current frame of reference by angle degrees counter-clockwise.

scale

x-scale y-scale scale -

This operator scales the current frame of reference by a factor of x-scale in the x direction and y-scale in the y direction.

translate

x-shift y-shift translate -

This operator translates the current frame of reference by x-shift in the x direction and y-shift in the y direction.

David Maxwell, who is still writing this, would like to hear your comments and suggestions. And remember, parts of this manual are based on P.J. Weingartner's work: A First Guide to PostScript.