- Restore render interrupt and progress
- Clouds are lighted without filtering from ground (clouds lighted at night !)
- Camera should respect ratio aspect of render area.
- All noises should use the same entropy pool (saved separately), and avoid reallocs.
- Implement light multi-sampling (mainly for skydome).
- Implement scaling and scrolling on previews.
- Water and terrain LOD moves with the camera, fix it like in the wanderer.