water_surface

The demo's water. A blend-queue surface shader that reads the lit opaque scene standing behind its own fragment, displaces that read by the slope of a wave field it builds in the surface's own tangent frame, absorbs it through the water's colour, and lays a Fresnel sky sheen, a sun glint and shoreline foam over the result.

Because the wave field lives in the surface's tangent frame rather than in world XZ, the one shader serves a level pond, a sloping channel and a vertical fall: flow is metres per second along that frame's two axes, so a fall scrolls its foam downward and a channel scrolls it south.

Its shoreline is measured, not authored: the shader compares its own fragment depth against the opaque scene's depth at the same pixel, so where marble rises through the water the surface fades out and turns to foam instead of cutting a straight line across the stone.

Consumed by noon.water through water_court, water_flow, water_fall and water_still.