Tips and Tricks

["Werner D. Streidt" <wstreidt@bigfoot.de>]

Hi there,

So, you've managed to program a bit with your own filter. Now you want to
include the calculations feature in the code, huh? No need for that,
although I've mentioned the algorithms in my Programming Guide. Why? Coz:

I assume we are talking of two images wanting to be "calculated" (like
multiply, screen, etc...). One image is the one you're creating with FF/FiFo
and the other one is the image you're aplying the filter on.

a) You can leave the calculations to Photoshop's layer calculations. Thus:
Create a new layer above your background layer and apply your filter to the
layer above (don't forget to push up the opacity in channel a). Then select
the layers palette and select the calculation you want. This should work
with PSP, too, right?

b) Another possible combination of calculation: Apply the filter without
calc on your image (background layer). You can now select in the menubar
"Filter -> Fade...". You can change the calc mode here, as well.

I also forgot to mention that in both ways you can change the opacity as
well.

Experiment and see what you can come up with!

Wern
http://privat.schlund.de/filter-factory    Home of the FF Programming Guide