Rendre

Rendre is the renderer a design student opens before they can afford the expensive ones — a WebGPU path tracer that runs entirely in your browser, live and free. Right now.

Import a model (OBJ, STL, glTF/GLB, or Rhino 3DM) and it lands auto-scaled and framed. Drop one of hundreds of PBR materials and tune it in a live editor — including real path-traced glass that tints by thickness and throws colored fire on a cut gem (dial it by Fire, or by the real Abbe number opticians use for actual glass), brushed metal with directional highlights, velvet with a soft subsurface terminator, a thin-film coating that tints by wavelength interference (anodized metal, oil slick, soap bubble), clearcoat, sheen, and procedural Italian marble computed without UVs. Light it by swapping the HDRI studio — whose own light recipe you can now open and remix strobe by strobe — or drop in your own; place a rig of real lights you can still recolor after the render’s finished; rack exposure, depth of field, bloom and a touch of chromatic aberration. Pose parts with a gumball you can drive by eye or by typing exact numbers. Then render: a clean PNG up to 4K, a transparent cutout dropped onto your own background image, per-part mattes for finishing in 2D, a six-up contact sheet, an A/B wipe, or a QuickTime video — queue a batch of any of it and walk away, or hand the whole scene to Rhino / Blender as a GLB. Every render can carry its own re-openable recipe quietly inside the file, if you want it to. Heavy models orbit as a light proxy and render at full resolution.

It’s a dedicated renderer, not a modeler — you bring a model and Rendre makes the picture, real path tracing all the way, with a color-managed look. And it holds the one rule the whole family is built on: the viewport is the render. What you frame is what you get; there is no separate “final” that surprises you.

Rendre grew out of the render room inside glisten — the same WebGPU tracer, pulled out to stand on its own. A desktop edition — a focused hard-fork of Blender — is in early development for the Fall 2026 semester; for now. For a closer look across a batch of renders, hand them to Juxt — a companion comparison tool, built alongside Rendre and open to anything you drop into it.

Light Rig & AfterImage — the light isn’t baked in until you say so

Six presets — Three-Point, High Key, Sweep, Rim, Dramatic, Sunset — drop a whole rig of real lights around the model at once and dim the studio down so they have room to read; add your own and drag it into place by azimuth, elevation, distance and size. Then the part that’s actually new: pick each light’s color and intensity — even after the render has already finished — and the image recomposites instantly, no re-render, because every light’s contribution to the pixel was kept separate from the very first sample. Placing a light is still a real, physically simulated bounce; changing its color afterward is free.

And it travels with the image. Every still you render can quietly carry its own light data inside the saved PNG — drag that PNG back onto the viewport later, no model required, and a dedicated AfterImage view opens: just the render and a slim panel of on/off, color and intensity per light, still instant. A crit note becomes “try it warmer,” not “render it again and get back to me.”

eight things worth dropping a material on

Drop a glass or gem material on a part and it doesn’t fake refraction — it bends real rays through the surface, tints by thickness, and throws colored fire the way a cut diamond actually does. Dial the dispersion slider from a plain windowpane up toward diamond-strength and watch white highlights split into color as they refract. It costs samples — glass and gems are the one case worth switching to 512 or 1024 spp — but the light is really doing the work, not a shader pretending to.

Metal doesn’t have to throw a round highlight. Dial Aniso up and the same roughness value smears the gloss into a directional streak — the look of a lathe or a brushing wheel, not a photo of one. It’s locked to world space on purpose: turn the part and the grain stays put, the way a real brushed part would if you spun it under a fixed light. Pair it with any metal in the library, from steel to 24k gold.

Marmo is stone with no photograph anywhere near it — the veining is computed on the surface itself, so it wraps a part with no seams and no UVs to unwrap first. Pick a structure (veined, clouded, breccia, speckled) and then actually edit it: vein color, how tight the pattern runs, how much it warps, even the iron-oxide bleed. Calacatta, Nero Marquina, Verde Alpi and a dozen more come loaded, and every one of them is a live recipe, not a swatch.

This one isn’t a color you paint on — it’s a thickness, in nanometers, that produces one. Dial Interference up on any material, metal or glass, and light bouncing through the coating interferes with itself the way it actually does on a soap film or an anodized part, shifting hue as the thickness (or your viewing angle) changes. Pair a low coating IOR with a brushed metal for anodized titanium; push it further for an oil-slick sheen. Past about 1000nm it stops reading as one color and starts repeating into rainbow rings — which is also physically correct, and occasionally exactly what you want.

Swap the studio and the whole render relights at once — every reflection, every shadow, the highlight crawling across the gloss. Flip “Behind the model” on and the backdrop becomes the actual image lighting your part, not a hidden trick — drag Rotation and watch the highlight cross the surface in real time, because now you can see exactly why it’s doing that. Over thirty studios ship in, from a plain three-point setup to colored backwashes that’ll fight your material for attention.

Double-click a studio thumbnail and you’re not just told what’s lighting your model — you get to touch it. The real recipe opens: the actual named lights the studio is built from (Key, Fill, Rim, and whatever else went into it), each with its own intensity, position and size, in a live mixer next to the dome it's painting. Turn one off, retint another, add one of your own — it isn’t a black-box composite you accept, it’s a rig you can put your hands on.

Shots is the fast way to a video: pick a ready-made move instead of hand-keying a camera. Orbit the whole form, dolly-zoom for drama, sweep the specular highlight to sell the gloss, boom up to show scale — a dozen moves, each one already scaled to fit your model, not yours to calculate. Preview it right there, then hit Render and it hands off to Film to pick size and samples. You’re still the one who decides when it’s actually done.

When you’re done lighting and want to keep going somewhere else, hand the whole scene off as a GLB — every part at true scale, in millimeters, each material translated into Cycles’ own vocabulary, the camera, and the lighting cited as a real reference: which studio, its rotation and intensity, a link to the actual .hdr. It also tells you plainly what doesn’t survive the trip — the infinite floor, hidden parts, the environment image itself — so you’re not guessing what changed when you open it in Blender or Rhino.

Rendre isn’t the first renderer to try this, and it won’t be the fastest one you’ve used — that’s the trade a single HTML file makes. Open it and every ray on your screen was traced right there, on the machine in front of you, nothing installed and no cloud GPU quietly finishing the job somewhere else. Real-time was never the point. Believable material on something you’re actually about to make is.