Performance drop when particle emitter is combined with video play

Hi All,

We're a studio building an app and as part of a scene we have a 3D asset with a smoke particle emitter and a curved mesh that plays video. I notice that when the video alone is played or the particle effect alone is done then the scene works fine but the frame rate drops drastically when both are turned on.

How do I solve this because this is an important storytelling feature.

Answered by Vision Pro Engineer in 862799022

Hi @krcnow,

Is your smoke particle transparent? If so the transparency can cause a lot of overdraw. If you can use opaque particles you should see much better performance. If you require transparent particles adjust their lifetime and on screen count to help reduce the overdraw. One way to think about it (not 100% accurate but a good mental model) is every transparent pixel between the camera and the opaque item behind the pixels is another draw that needs to be done for that pixel.

Accepted Answer

Hi @krcnow,

Is your smoke particle transparent? If so the transparency can cause a lot of overdraw. If you can use opaque particles you should see much better performance. If you require transparent particles adjust their lifetime and on screen count to help reduce the overdraw. One way to think about it (not 100% accurate but a good mental model) is every transparent pixel between the camera and the opaque item behind the pixels is another draw that needs to be done for that pixel.

Awesome, this seems to be very helpful. I was able to reduce the lifetime and count and bring it under control.

Performance drop when particle emitter is combined with video play
 
 
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