Today I drew my first river in pOqpOq World. I dragged a line down a hillside, let go, and a moment later there was water in the creek. It wasn’t painted on: the creek was cut into the ground, it sat in pools, and it stepped down the slope the way real water does.
The water comes from Burble, our water studio. Burble is where we work out water that isn’t the sea: springs and seeps, creeks, falls, branches, deltas and marshes. We work it out one chapter at a time on simple test ground, and only then bring it into World.
Water that holds. The rule Burble lives by is simple to say and fussy to keep: water has to stay where it’s put. A creek on a slope is really a chain of small pools, each held back by a sill. Burble checks every pool before the creek appears: the water level has to sit below both banks, all the way along. If a pool would spill, you don’t get a broken creek: Burble holds it back and tells you why.
If you’d rather see it than read about it, the video above is a walk up a mountain stream in World, and then a go at reshaping the water corridor live in the path editor. It also shows the rough edges, which is the point of a walkthrough: you spot what feels wrong and give yourself a better way to fix it.
What it does in World. When you draw a river, Burble:
- Settles it into the land. The slope becomes a staircase of pools and steps, with white water where it tumbles over each sill.
- Cuts the channel into the ground you walk on. The bed and the banks are real terrain, so you can walk down to the water’s edge.
- Lets you choose where it starts and ends. A spring, a seep, snowmelt or a lake’s edge at the top; the sea, a lake or a sink at the bottom, with a delta or a marsh if you like.
- Lets you shape it. A natural creek or a built channel, how much water it carries, and a side-on profile where you can drag a step’s height and lock it.
- Keeps it while you garden. Raise a hill or dig beside the creek and the water stays put.
Where it’s heading. The creeks now have their own surfaces: cobble in the bed and a soft clay bank fading into grass. Next come falls with real stone, branches where two streams meet, moats around a castle, and bridges to cross them. Closer in, stone size that stays constant as a creek widens, and more variety in the splash and foam at each fall. Each one gets worked out in the studio first and then comes into World.
Notes from the build
A running log, newest first.
October 6, 2026
- Rivers draw their own surfaces. The bed, the clay bank and the cut face are painted through the terrain’s own materials. Before it shipped we checked that the rest of the terrain is unchanged: pixel-identical on WebGPU, and within measurement noise on WebGL2.
- Dragging water is lighter. While you edit, the preview used to rebuild every piece of its mesh ten times a second. It now reuses its pieces. We chased a GPU resource leak to that.
- The staircase was too regular. The walkthrough showed a bit too much “staircase energy”, so a creek’s step rhythm is now yours to tune. Tread bias runs from short runs (×0.5) to long runs (×2) between drops, Lip variety from straight lips to broken stone lips, and Bank relief from smooth banks to rough ones. A per-reach seed, to reshuffle where the drops land one creek at a time, is coming.
- Bigger creeks. The volume range now goes up to 64, about a 4 m wide stream. We benchmarked it: 64 costs roughly 40% more settle time, which is fine for everyone. River-sized water needs more work first.
- The pinch at the tight bend. In the video, flat beige panels sit under the grassy lip. It looked like broken geometry, but it’s texture mapping: some bank triangles stand exactly vertical, and a texture projected from above collapses to a single colour on a vertical face. The fix, now live, maps steep faces from the side, so walls show real stone and soil. Where a wall meets flat ground you may spot a faint texture seam along the crease; a smoother blend is on the list if it shows.
- A tip. Fly before you remodel the ground under your own feet. Your avatar gets a polite nudge when the terrain changes beneath it. A proper fix is filed.
If you’d like to dig a creek of your own, or just sit beside one, pOqpOq World is looking for alpha testers. Bring a friend and build something by the water.
— Allen