In addition to sizing (size=) and positioning (pos=) layers relative to layer 0 and specifying the compositing order (the z-order) with the layer= command, layers can be rotated (rotate=) and flipped (flip=).
anchor= attributes may be used to maintain the desired alignment between layers when images or text are changed dynamically in templates.
maskUse= command is available for image layers to access the background area of images which have separate masks.
opac= can be used to vary the layer opacity, and
hide= to show or hide the layer.