Re: [AD] memory bitmap blending

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On 2008-11-28, Trent Gamblin <trent@xxxxxxxxxx> wrote:
> On Fri, November 28, 2008 3:50 pm, Trent Gamblin said:
> > On Fri, November 28, 2008 3:39 pm, Peter Wang said:
> >> In case you didn't know already, these combinations aren't yet fixed:
> >>
> >>     src=ONE, dest=ALPHA
> >>     src=INVERSE_ALPHA, dest=ONE
> >>     src=INVERSE_ALPHA, dest=INVERSE_ALPHA
> >>
> >> Additionally there are obvious visual differences with these:
> >>
> >>     src=ONE, dest=ONE (overexposed look)
> >>     src=ONE, dest=ALPHA (overexposed at a=0.5)
> >>     src=ALPHA, dest=ONE (overexposed at a=0.0)
> >>     src=ALPHA, dest=ZERO (mysha invisible at a=0.5)
> >>     src=ALPHA, dest=ALPHA (overexposed)
> >>     src=INVERSE_ALPHA, dest=ALPHA (mysha invisible at a=0.5)
> >
> > Ok, I'll take a look at those and see what I can do.
> 
> I just looked at all of them and they look identical on Windows/D3D.

Here are screenshots of what I see for the first three.
(low quality to avoid spamming the list)

src=INVERSE_ALPHA, dest=ONE
    src is mysha, a=0.0, so there should be a contribution
    from mysha right?

src=INVERSE_ALPHA, dest=INVERSE_ALPHA
    a=0.0, so the contribution from both should be full

Unless I'm misunderstanding how the blending should work?

Peter

Attachment: one_alpha.50.jpg
Description: JPEG image

Attachment: invalpha_one.50.jpg
Description: JPEG image

Attachment: invalpha_invalpha.50.jpg
Description: JPEG image



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