This is an example.
When transparency of the part is 0, it looks like this.
However, if transparency is above 0.011, it looks normal.
Is this intentional? Because it’s pretty gross.
Expected behavior
It would look like the second picture, even if transparency was at 0.
actually, it’s 0.011
Thank you for the clear example and details on the workaround.
This is a result of the special case of MeshPart.Transparency being set to 0 described here:
There are effectively two blending techniques, activated by a zero or non-zero transparency. This is not very discoverable – an update to improve the documentation will follow shortly.
It is safe to change the transparency to a small value to activate the smoother blending. We will ensure that setting to 0.02 or greater will continue to have this behavior in later updates so that it won’t break your experiences.
Please be aware that with the 0.02 or greater value, that some depth-based effects and occlusion will not work as well. This includes effects like DepthOfFieldEffect, glass and water refraction, and water reflection…
Edit: Changed 0.2 to 0.02
is it possible that an option for the blending mode to be added? it is not really convenient to put 0.2 or any transparency to the part, i think that also does something with the drawcalls.
also when i use a transparent texture and then i add a neon part under it to get some sort of emissive texture it looks the same like in the first picture, i bump up the transparency and it looks fine but my worry is that when i make the part transparent on top of a picture with an alphamap it just makes performance worse
sorry if reading this led you to a stroke I’m not the best at english
After some further consideration, we’d like to leave the option open to change this behavior to a more convenient and intuitive method.
For now we recommend to continue using a small value, such as 0.02, for the transparency.
If such an update invalidates this workaround, we’ll be certain to communicate the details.
Is there a specific reason as to why this is the case? From what i could see with software like render doc, is this issue not just a geometry depth and shader ordering issue?
The creator docs will be updated shortly with more detail. In short, there are two kinds of transparency that are selected depending on if the part transparency is set to 0 or non-zero. (It must be a number slightly larger than 0 to ensure it doesn’t get rounded to zero during lower precision calculations).
When 0, a screen-door / dithering effect is used. This is very efficient and works well with depth based effects and occlusion, as it is effectively still rendered like an opaque object. Antialiasing techniques can hide some of the dithering, but it can still result in effects shown in this bug. This is the most ideal way to render things like foliage, lace, and netting.
When non-zero, a true alpha blend is used. This is less efficient and doesn’t work as well with all effects, but can show smooth, continuous gradients of alpha transparency. This is best for cases like the glass window in this bug.
We’ve updated some pages in the Creator Docs with these details:
another thing that this problem ruins:
this is supposed to be a fluorescent light with a transparent colormap and neon part under it to simulate emission maps (please roblox add emission maps you already have it on lava material) and this is how it looks like
however, if i increase the transparency by a bit the alphamap becomes smooth, but the occlusion becomes buggy
