7/2/2004 SSCC/NIMH 53
Dset Controls block
¥Dset Info Table:
HRow. Lbl: Label of Dset.
HRow. Par: Parent surface of Dset.
¥Ord:
HOrder of Dset's colorplane. Dset with highest number is on top of the stack. Separate  stacks exits for foreground (fg:) and background planes (bg:).
¥Opa:
HOpacity of Dset's colorplane. Opaque planes have an opacity of 1, transparent planes have an opacity of 0. Opacities are used when mixing planes within the same stack  foreground (fg:) or background(bg:).
HOpacity values are not applied to the first plane in a group. Consequently, if you have just one plane to work with, opacity value is meaningless.
HColor mixing can be done in two ways, use F7 to toggle between mixing modes.