mirrorpool

MIRRORPOOL — a WebGL2 VIDEO source rendering a hemisphere pool of liquid inside a box, viewed by a full-PTZ camera you fly around within it. TWO video inputs feed the optics: POOL is surface-mapped to the INSIDE of the hemisphere (the underwater view you see refracted through the water, with Beer-Lambert depth absorption + chromatic dispersion) and SCENE is the surroundings, reflected off the surface as an overhead backdrop (projected to the box ceiling so a camera pan slides a RECOGNISABLE reflection, not a lat-long smear). A single REAL height field drives all the optics — not a flat normal-map fake: WIND raises a set of 4 directional swell waves whose amplitude grows with wavelength (dispersion omega=sqrt(g*k), so bigger crests are genuinely TALLER and travel FASTER), and RAIN runs a seeded Poisson scheduler spawning raindrop impacts that punch one-shot dimples which expand into propagating rings — sparse shallow drizzle up to a dense deep downpour. The surface NORMAL reconstructed from that height field (by finite differences, one consistent sign convention shared by the sim + swell so they never cancel) drives a physically-based Schlick FRESNEL split (water F0=0.02, eta=1/1.33). In the default REFRACT mode (MODE=0) you see the reflected scene layered over the refracted, caustic-lit pool beneath; sweep MODE toward MIRROR (1) and the surface becomes a near-full mirror of the sky/scene that the ripple normals shatter and distort — one continuous CV-friendly scalar, no branch. BRIGHT is a virtual sun scaling overall scene light uniformly (no sun disc drawn yet). The camera is a repositionable ORBIT + FREE-LOOK rig surfaced as the card's TWO X-Y pads: pad 1 POSITIONS the eye on a sphere around the pool (Orbit = azimuth around it, Elev = elevation from straight overhead down BELOW the water surface, plus a Dist dial), and pad 2 is the free-LOOK offset (Look X = yaw, Look Y = pitch) off the default aim-at-centre so the view can point any direction; Zoom sets a 70..20 degree FOV. Dropping the elevation below the surface flips the render into an underwater Snell-window path (a bright refracted cone of the sky/scene overhead, ringed by total-internal-reflection of the pool interior). Every control has a matching CV input (port id == param id + `_cv`), so patch an LFO into orbit_az_cv for a slow orbit, noise into rain_cv to gust the storm, or an envelope into surface_mode_cv to melt between a clear pool and a hard mirror. The rain wave sim runs as a float ping-pong wave-equation FBO when the GPU exposes renderable float targets, and falls back to an analytic expanding-ring model in the render shader when it does not (isFloat=false, e.g. some SwiftShader configs) so rain is never a dead field. Rendered at half engine resolution and LINEAR-upscaled (the mandelbulb perf discipline). With nothing patched it still renders a live procedural sky + rippling water, so it doubles as a standalone generative source. All ports live on the yellow drill-down PATCH PANEL (no raw side jacks). The pure physics (Fresnel / swell gradients / normal reconstruction / Poisson rain / orbit + free-look camera) is unit-tested in $lib/video/mirrorpool-core (the exact CPU mirror of the shader).

mirrorpool renders a hemisphere pool of liquid sitting in a box, viewed by a repositionable ORBIT camera you fly around the pool. Two video inputs feed the optics: POOL is surface-mapped to the INSIDE of the hemisphere (the underwater view you see refracted through the water) and SCENE is the surroundings, reflected off the surface as an overhead backdrop. A single real height field drives everything: WIND raises a set of directional swell waves (bigger waves are genuinely taller and travel faster — dispersion, not a flat normal-map trick) and RAIN spawns raindrop impacts that punch one-shot dimples which expand into propagating rings, denser and deeper from drizzle up to a downpour. The surface normal reconstructed from that height field drives a physically-based Fresnel split: in the default REFRACT mode you see the reflected scene layered over the refracted, caustic-lit, colour-absorbed pool beneath; sweep MODE toward MIRROR and the surface becomes a near-full mirror of the sky/scene that the ripples shatter and distort. BRIGHT is a virtual sun that scales overall scene light (no sun disc is drawn yet). The camera is the card's TWO X-Y pads: pad 1 POSITIONS the eye on a sphere around the pool (Orbit = azimuth around it, Elev = elevation from straight overhead down BELOW the surface for an underwater Snell's-window view) with a Dist dial for how far out it sits; pad 2 is the free-LOOK (Look X = yaw, Look Y = pitch) that swings the view off the default aim-at-centre so you can look any direction, and Zoom sets the field of view. Every control has a matching CV input, so patch an LFO into orbit_az_cv for a slow orbit, a noise source into rain_cv to gust the storm, or an envelope into surface_mode_cv to melt between a clear refractive pool and a hard mirror. With nothing patched it still renders a live procedural sky + water, so it works as a standalone generative source.

the faceplate

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source

mirrorpool.ts on GitHub.