Wind effect adds visual bug to trees leafs added via vegetation system

[Dreikblack]

Pretty sure there was post about that by Alienhead, but i can't find it now.

Example map:veg_test2.zip

 

[Josh]

I can't tell what is going on in that screenshot. Are the leaves moving? Is the shadow moving?

I created a test scene and saw nothing wrong.

1. Create a new project.
2. Install the Realistic Maple Trees asset.
3. Extract this zip file to the project. This will overwrite one material file.
4. Open the included scene in the editor.

windtest.zip

[Josh]

Okay, on my Nvidia card only, I am seeing a strange artifact, only on the vegetation layer instance, not the model.

 

[Dreikblack]

Yep, thats it. It happens in game, not in the editor

[Josh]

It happens in the editor too, You can enable real-time rendering with this:

It still occurs even if I disable shadows. Looks like the normal is being affected, and it's not lighting correctly? Hard to see because it just flashes on and off.

[Josh]

Looks like it is bits of the background visible, as if the early z-pass depth value does not match the visible pass.

[Josh]

As far as I can tell, it appears the early z and visible passes are producing slightly different results in the construction of the instance 4x4 matrix from a texture lookup, even when both shaders execute the same exact code. This causes a discrepency in the resulting normal, which causes some pixels to become invisible.

If I move lighting into a deferred step and eliminate the early z pass this problem will go away.

[Josh]

This feature will not be available until lighting is moved into a deferred step.