I have an object that is about 1.5 million polys and had modifier stacks which select the mesh over time and applies a delete mesh. Trying to xmesh an object setup this way is a nightmare. The saving time exponentially goes up per frame. Starting at 1 minute to 50 minutes per frame after 150 frames or so.
Wondering if anyone had this issue before. I remember having a similar issue last year when using same technique of modifiers.
Can you please provide a simple scene that reproduces the problem (specifically the modifier setup you are using). You could apply the same setup to a high-polygon geosphere or something.
Out of curiosity, what happens if you try to render your setup without saving to XMesh - does each frame take the same time, or does it go up exponentially, too? XMesh should behave like a renderer (in theory), so trying Scanline, mental ray or VRay on your setup would be a good place to start. If the renderers render in consistent times per frame, then the problem would have to be in XMesh. If you get the same exponential behavior, then there might be something going on in your modifier setup outside of XMesh…