In 2.80, using a png decal on an image plane worked good using the alpha blend mode. However, when opening the same scene in 2.81, I can see the background of the decal now. I attached an example of what is happening.
As you can see, this decal has the semi transparent bg that shows now. How do I fix this?
here is the current node setup
That might happen if the alpha isn’t pure black and white, it only has to be a smidge off to show up. Try putting the alpha through a colour ramp or a contrast node and pushing it, see if the issue goes away.
thanks for the reply, but unfortunately it did not work. Its just odd, worked perfect in 2.80. Seems 2.81 doesn’t like it for some reason.
Can you share the png image?
looking more into this, it appears to be caused by using a volume scatter. if i disable that, the decals look good. But when enabled, the background shows. This didnt happen in 2.80
Decal png looks okay to me. I suggest reporting it as a bug if it was fine/better in 2.80.
Odd, when I download the decal and pull it into xnview, i go to extract the alpha channel and it isn’t active. Loading it into Serif Photoplus, it came in with the outer part black, not alpha. I edited the image and re-exported it as 32-png and tried it in 2.81
It works just fine in both eevee, (with alpha hashed for the viewport display) and in cycles, as can be seen from the attached screengrab. The object is a uvmapped cube, with decal applied only to one face.
try taking that png and use alpha blend, then add a volume scatter or principled volume. You will see the box outline. This didnt happen in 2.80.
This will certainly not help you, but in 2.81 I encounter issues with volume scatter : I oppened a file from 2.8 with a volume scatter node plugged in world output, and both eevee and cycles are unable to render (everythings black) while it works fine in 2.8.
So might be related, I’m still trying to figure it out !
