I have a large level sequence with lots of actors with keyframes of “Actor Hidden in game”. When I open the level sequence in the Editor and scrub through, all of the actors are hidden and shown properly, but when I use the Movie Render queue, this property becomes completely broken. Some actors that should be hidden are not and others that should be shown are hidden.
I’m using the level sequence to get a bunch of camera screenshots, not to render an animation. I have one camera shot per frame for each frame, then animating the actor hidden in game property depending for each camera shot. Not sure if this is useful info, but thought I’d add it. As well, I’m using the Pathtracer to render images, but this seems to happen with deferred rendering as well
Does anyone have a similar issue and knows of a possible fix?
Upon testing further, here are some things I found:
This seems to be not only an issue with “Actor hidden in game” but all binary keyframe properties. I just did a test with key framing “cast shadow” and it also has the same issue.
I think this might be related frame mismatch in the level sequence in editor vs movie render queue. Maybe as the MRQ chugs along, instead of going to frame 5, it goes to frame 4.999 for example. This won’t be noticeable for a continuous animation like moving an actor, but obviously might break for binary keyframes. As far as I know, the level sequence does intra frame interpolation to smooth out animations. If I set the binary key frames back just 1 frame in level sequence for some actors it fixes for that object so perhaps this is part of the problem.
Related to the above, I thought that changing the FPS might help. My level sequence is 30fps, I tried changing to slightly higher or lower to fix the above issue, but it just broke it even more.
I figured it out, it has to do with how the MRQ samples each frame. This happens mostly when you have lots of temporal samples. Using many temporal samples, the MRQ samples each frame a bit before and after that frame. For smooth keyframes like moving an actor this is fine, but for binary key frames it causes this issue.
To solve this, in the Movie Render Queue settings, add Camera setting, and set shutter timing to Frame Open.
This honestly seems like a bug, by default binary key frames should always be treated as Frame Open. I’ll submit a bug report about this.