ARexx scripts are run before and after each image is rendered, and before each 24 bit image is loaded. The script names can be supplied as parameters (LOADSCRIPT, PRESCRIPT and POSTSCRIPT) to TSMorph-render.
An ARexx script can also be run by TSMorph to preview render an image. The script name is supplied in the PREVIEW parameter.
The suffix to each ARexx script should be .TSM.