Opactiy mapping misery

[FrostKiwi]

Hey,
I have many decals in the form of either dirt overlays, Pictures or signs on walls, imported as TGA's with a an alpha channel.
Alpha works in Vray, Scanline but not corona.
I tried every possible combination of checkboxes for Alpha interpretation and threw in many Corona textures in between, nothing seems to interpret alpha correctly.
Am I missing something here?
With settings that works for other renderes, Corona seems to interpret Rgb as alpha, although I dont have it chosen in the Bitmap setting (image 1). If set RGB mode to ALPHA as gray its works, but obviously without RGB color (image 2).
I can't possibly export a second bitmap with gray values for Alpha for 300+ textures (without going mad, that is)
I tired all workarounds mentioned here: https://forum.corona-renderer.com/index.php?topic=1017.0

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[FrostKiwi]

Works when Importing the bitmap twice, once as RGB and once as Gray from Alpha, still a tedious step and would be great to have a workaround/fix.

[PROH]

Hi. Yes, you're right. Alpha doesn't work at the moment. It's a known bug, reported several times. I think (hope) it will be fixed in commercial release.

[FrostKiwi]

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Hi. Yes, you're right. Alpha doesn't work at the moment. It's a known bug, reported several times. I think (hope) it will be fixed in commercial release.

[borisquezadaa]

NASTY WORKAROUND

How about this nasty node solution?...
It seems alpha has gamma issues between photoshop and 3dsmax.
At least you dont have to import map twice just clone the node and put it between.
The gamma value i put it there i got it out of my ass i dont have a clue of the exactly number to counter gamma of alpha channel out of photoshop. Maybe counter a double 2.2 gamma (4.48)?... perhaps. Open to discussion.

I CAN SAY NOW THAT ALPHA GAMMA TARGAS WORKS in a fashion.

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