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With forward rendering is the shader complexity view of masked materials accurate?

In deferred rendering the transparent parts of a masked material are the most expensive and that is what is reflected in the shader complexity view. also when looking through a bunch of masked transparent planes you get overdraw.

However, if you stack a bunch of masked planes one after the other in forward rendering the shader complexity shows no overdraw.

in the pic attached I’m using msaa at around .5 masked opacity so the planes are translucent. if I turn off AA and set the opacity to 0 the planes become invisible but there in no overdraw shown. in fact the planes just disappear from the shader complexity view altogether.

I’m trying to figure this out because making trees and grass is way easier if masked materials don’t create overdraw in forward rendering since I could use lower poly billboards.

I am wondering the same thing, especially since the mobile forward renderer shows overdraw (and it’s severe!). I do however notice a slight drop in fps in the HQ forward shader too, if I look at lets say a tree crown with all leaves masked out vs all leaves visible. Which lets me come to the conclusion that overdraw is still a thing even though it’s not shown in the shader complexity view. I’m not 100% certain though either. Would be great to get clarification on this. I’m on UE 4.25