Orblit

Ten days ago I said Orblit had no physics solver. It has one now. Here is what landed since, and what is still unproven. Orblit is an open-source Dart 3D engine on Flutter, a C++ ECS and Filament. Docs are at https://orblitengine.com and the code is at https://github.com/ChxisB/orblit. Physics orblit_physics is a rigid-body solver in C++ behind a Dart build hook. It depends on nothing. The repo did not exist ten days ago and is now at 0.7.0. • Spheres, boxes, capsules and planes. Friction, restitution and damping. • Warm-started contacts, sleeping, and touch, sleep and wake events. • Shape casts and a walking character controller. • Terrain as ground, built from a height field. • Seven joint kinds: fixed, point, hinge, slider, distance, cone and six-axis. They take limits, motors and breaking. • World queries: overlap, point, all hits, closest, and rays with normals. • Triggers, zones that override gravity and drag, conveyor belts and per-pair rules. • Body controls: axis locks, gravity scale, speed and spin caps, centre of mass, inertia, and a switch between fixed, driven and free. There are material presets such as Ice, Metal and Rubber, pairs that ignore each other, and 32 named layers. Bodies are components in scene documents, so the editor edits them. I decided not to promise identical results across platforms. Animation • Clips and a timeline. The Fox model plays through Orblit. • Blends of clips that you can save and replicate over the network. • Retargeting a clip onto another skeleton. • Cutscenes, with a Cinematics workspace in the editor. Terrain • A clipmap terrain renderer with brushes, undo and picking. • Scatter places grass, stones and trees by rule. • The editor has a Terrain mode, and the gallery has a Terrain example. Editor • Three columns and task workspaces: Scene, Modelling, Terrain, Animation, Cinematics and Interface. • Named layouts and a Focus view. It fits in 960 px. • Linked prefab instances with overrides. • Inspectors for bodies, joints, triggers and zones. Docs and gates • New guides for physics, animation, terrain and cutscenes. Each compiles its Dart snippets in CI. • The older docs are rewritten in plain English. • A Claude Code skill in the repo teaches the API. • Lints and --fatal-infos now fail CI. So does commit lint on every commit. The screenshots show the editor on a demo project and the gallery's Terrain example. They show the controls, not bodies moving. What it still can't do • Nothing is API-stable. • Most of the above is proven by tests, not by a live scene. That covers physics, joints, terrain editing, blends, retargeting and cutscenes. No gallery example uses physics yet, so I have no video of a body falling. • Terrain has only drawn on macOS. • macOS is the reference platform. The iOS simulator, one Android handset and Chrome also run it. Linux works only with software rasterisers. Windows builds but has never drawn a frame. • Ignore rules do not cover characters. • Retargeting has not run on a real character pair, and feet are not pinned. • There is still no asset store. The help that would matter most • Build something small with the physics and tell me where you gave up. • Run it on hardware I don't have. Windows and real Linux GPUs first. • Argue about the API before it freezes. • Send PRs. CI is strict.