RE: [AD] Question about 256 colors modes

["Vincent Penecherc'h" <Vincent.Penecherch@xxxxxxxxxx>]

> I don't get which "program" do you say I've "told" to
> generate black or transparent.

The graphics program you used to create the image (which
you said to be, eg, Photoshop).

What I meant is, as far as that program's concerned,
there isn't any reason to make black transparent if
you haven't told it to (eg by having a mask, or similar).
From what you said earlier, I think you haven't "told"
eg Photoshop that you intended whatever black bits of
your images to be interpreted as transparent, so that's
probably why black went in as a random place in the
palette (254 in your case), as black doesn't have any
particular significance for it, as opposed to a color
which is transparent.

In any case, if you want to create 8 bit images, you
will have to control the palette, or you'll likely run
into more problems (eg, if two sprites sharing the same
palette do not actually have the same palette ordering
due to eg Photoshop generating different orderings. If
you already manage your palettes, then you'll know where
your black and transparent colors are, so this will not
be a problem.

Again, I have to guess at what you may be doing, so this
may or may not apply.

> - I've used another platforms (and hardware) where the
> index color for transparent can be set, and didn't
> found any significant delay. May be on allegro is not

Possibly, I was just saying this to make sure this got
considered, I do not have timings or anything. All I
know is that, out of 7 usable general purpose registers
on x86, I've always found I could have done with a few
more :)



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