Marshes east of Ohlun

The marshes east of Ohlun finally hold rain the way the marshes east of Ohlun should.

Three weeks of fluid simulation work. The old implementation used a volumetric approximation that ran fast and looked fine from a distance, but up close the water pooled in cells instead of flowing. A player kneeling by a reed bed would see the illusion break.

The new pass is slower — about 40% more per-frame on the water shader — but it holds together. Rain on a heavy day now runs off the peat, gathers in the low places, and moves. The altar near the west fork sits a pixel lower than it did last week because the water now runs under the stone and I had to adjust its anchor.

A small note on performance. The old pass ran at 2.1 ms per frame on the reference machine. The new one runs at 2.9 ms. I spent a day and a half trying to claw back the difference and got nowhere I was willing to keep. So the water is slower. So be it. The water is also right.

This is the kind of work nobody sees and that becomes everything.

I am tired and I am not stopping.