Fixes issue where warp effect looks wrong near the edge of the screen -
there was an unhandled `REGION_CLAMP` texture setting.
Fixes a potential bug where "warp page" things wouldn't be drawn at all
because there is no PC warp bucket. Unclear if anything actually fits
this category, but it doesn't hurt.
Turn on PC-format texture uploads for the water page so the precursor
guy uses the right texture. It has to use generic because it abuses the
generic death query thing to spawn particles.
Workaround for some issues with rebuilding level files after changing
engine files. Not a perfect solution, but probably good enough.
- Disable depth test for sprite glow (VU1 programs only `sq.xy` and
leaves `z` alone, which has Z_MAX from the template)
- Fix tfrag/tie/shrub issues when `use-camera-other` is set.
ManDude