The per-frame redraw caused texImage2D upload of 8MB every frame,
which the browser couldn't keep up with -> tiles disappeared.
Reverted to refetch-based updates but with two key changes:
- Corridor 25 -> 50 tiles long (~6 min of flight at uSpeed=1
before refetch)
- Tiles redraw with fractional camera position, so the corridor
tracks the camera smoothly within the loaded content
The 50-tile corridor covers enough flight time that refetches
happen rarely (~6 min), but the camera's continuous position
is still reflected in the mosaic's center. So between refetches
the visible content scrolls smoothly.
Richard Zink
91ff8fb9d7