[PD] GEM problem with [alpha] on MacOS

[Matteo Sisti Sette]

Ohhh,

I think I've realised what my problem is, not with [alpha] at all.

I think the colorspace being used by default happens to be RGBA on my 
linux PC and YUV on Mac OS.

So a [pix_rgba] should solve my problem and elminate all differences.

Just out of curiosity, who is responsible for determining the color 
space used by default?

thanks
m.


On 02/25/2011 12:17 AM, Matteo Sisti Sette wrote:
> Hi,
>
> The attached patch works as expected in Linux, but in Mac OS the
> rectangle with the texture generated by pix_movement is not transparent.
> It is a black-and-white opaque image.
>
> [pix_movement] SEEMS to be working as expected and generating the
> correct alpha channel (judging from the values I got with a [pix_blob]
> in mode "4"), so I think it is [alpha] that is not actually enabling alpha.
>
> I have Linux and don't have a Mac, and when I observed the issue I
> couldn't take the time to do the obvious tests (such as trying with a
> solid color with alpha and no texture at all, and trying pix_image with
> a png image with alpha channel).
>
> Can anybody confirm this?
>
> I also tried sending [alpha] a "1" on the left inlet (not necessary in
> linux), just in case alpha was disabled by default in MacOS but that
> didn't help.
>
> Is there some extra thing I have to do in order to have alpha work in
> Mac OS?
>
> I am using GEM 0.92.3 in Linux and I think the same in Mac (the one
> bundled in the latest Pd Extended).
>
> Thanks in advance
> m.