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Render order priority possible?

Is there any option to set render order for objects in UE4? This is kind of crucial even for opaque objects in mobile projects to avoid unnecessary overdraw.

Whats the default order UE4 renders objects in the scene, what we are seeing is that its going from back to front and this introduces huge overdraws that could be avoided by depthbuffer if the order was from front to back.

Thanks for any info.

It should be rendering opaque objects front to back, How do you know the order that they are being drawn in?

I don’t know the order thats why I am asking but what we are seeing is unusual performance issues due to fill rate with just 2 walls when the first one is totally occluding the second one so the second one should be discarded by depth test which doesn’t seem to be the case. I am talking mobile here no geometry occlusion comes into play basically testing with simple geometry and moderately expensive material.

Is there a way for more finegrained GPU profiling/debugging in UE4? Something similar to PIX which we are using for our in-house engine? Or we need to utilize 3rd party software for that and what you guys are using in such case? I am definitely looking into the stuff you have in your signature so thanks in advance, btw does it work with mobile PIE as well or is crucial to do on device profiling?

There is a plugin for RenderDoc here.

There was a built in console command to profile the GPU, You can read more about that here.

Do you have “x” enabled in the rendering options of the project settings?
Have you placed/built occlusion cullers (there is a button under the “Build” menu).

Under the project settings I have these enabled(This is a desktop project tho):
Culling:
Occlusion culling.

Optomizations:
Early Z-pass on auto.

Are the wall materials opaque?, Because IIRC transparent materials are rendered after everything else and are pretty expensive(relatively speaking anyway)

There is also the “Rendering Best Practices”](https://www.youtube.com/watch?v=-csRxRj_zcw) Twitch livestream.

HTH

Yep I already started using RenderDoc with the plugin and its simply amazing, actually it may have already pointed out the problem in our case which is instanced meshes, to simplify the explanation its somelike like other instances of the 2nd wall are closer to the camera than the 1st wall, although it should be frustum culled need to examine further.

We already use ProfileGPU but its very vague especially for mobile projects its almost empty (just base pass with single item, lighting) so its not much of a help, definitely looking forward for better GPU profiling Epic guys are working on.

I don’t use occlusion culling since it doesn’t work for mobile, precomputed visibility would work but is not feasible for our game level hierarchy. All materials are opaque I mean transparency is killer on mobile anyway and Z-Pass is on auto.

Anyway big thanks, especially for the RenderDoc which will be a huge help to me with UE4 and outside.