Massive frame rate drop with Composure, normal?

Hi everybody,

I am currently using Composure in a very easy set-up. I have a very basic scene with a few meshes (3 Cylinders, 1 Plane and 1 Cube), a DirectionalLight and the default Sky. Really nothing that could explain performances issues.

I have the “3 layers” composition exactly as shown in the Unreal Engine documentation’s tutorials :

  1. A green screen video which is chroma-keyed (MediaPlate) ;
  2. A layer with the background elements (CG Layer) ;
  3. A layer with the foreground elements (CG Layer).

The Composition Material then simply organizes the layers order. Yet, this very simple example creates massive frame rate drop. And at that point I haven’t even started the video in the MediaPlayer. Everything is iddle and it’s already affecting the performances so much. If I toggle off the “Element Rendering” of the two CG Layer in the Composure window, I get my FPS back.

I stumbled across a post wich indicated that the problem is linked to Ray Tracing and that once disabled, the problem is gone. I indeed have Ray Tracing enabled in my project. However, I performed some tests and here are the results :

Ray Tracing enabled :

  • CG Layers “Rendering” disabled : ~120 FPS ;
  • CG Layers “Rendering” enabled : ~40 FPS.

Ray Tracing disabled :

  • CG Layers “Rendering” disabled : ~140 FPS ;
  • CG Layers “Rendering” enabled : ~90 FPS.

So the performances surely are better without Ray Tracing. But I still don’t find the result of my tests to be very convincing. Even without Ray Tracing I am currently losing ~25 FPS per “active” CG Layer and I can’t quite believe this is normal.

But maybe this FPS drop is normal and something users have to take into consideration when using Composure and adding new CG Layers ?

If somebody has any idea or informations, I’d sure like to hear them. Thanks in advance.

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Up. Help anybody ?

One last up. Hope somebody can help ?

Experiencing the same problem here, did you find any solution?

I have not been using Unreal Engine much recently but no, I have sadly never found a solution to this issue.
I think the way Compositing works is simply very harsh on the performances and it is something that needs to be taken into account.

Hello there,
Yeah, after work these last months with it, I arrived to the same conclusion, seems is not very optimized

Those are very good numbers for two CG layers and MediaPlate. Especially with Composure. In my view, Composure is still in Beta mode even if Epic didn’t recognize it, for several applications, but it will be so powerful, it’s just a matter of time!

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Has anyone found any workarounds for performance when enabling Composure in a project? Composure is slowing down the scene so much it’s unfortunately not usable in its current form. It would be nice to be able to turn on and off composure when working with the scene, and turn it on when doing final adjustments before rendering.