What rise-origin is

rise-origin is a GPU multiphysics engine for soft bodies, rigid bodies and fluids. It runs on one device, and it is the single-device edition of RISE. Its geometry is voxels today.

You describe a world in Python with rise_origin.rsc. The engine builds GPU buffers from that description and steps the world with CUDA kernels. Your program holds a handle, and it reads the running world and changes it through that handle.

The research station, built from voxels and lit by emissive voxels

Why the engine exists

rise-origin exists for research on bodies, perception and behavior. Soft tissue, rigid skeletons, the ground under them and the light a sensor receives all sit in one scene, so a body you generate can move, touch and see with no conversion step. Research published on the engine includes Endoskeletal (ICLR 2025) and ECo-MoE (ICML 2026).

Core concepts

A world and the program around it use five concepts:

• A world is the thing that runs. It holds structures, materials, lights, sensors and the time step.
• A characterization is the description of a world, built with rise_origin.rsc. It holds no device memory and runs no physics.
• A voxel structure is one StructureVoxel: bodies made of voxels, joined by constraints. A material decides whether a body is rigid, soft or fixed.
• A handle is what a program holds to read and change a running world, on the same machine or over the network.
• A module is a pure function under a versioned name. The create layer calls it with settings and a seed, and it returns content such as a tree or a rock.

What the engine does and what stays with you

The engine does these parts of the work:

Part	What the engine does
Import	Voxelizes meshes, and imports URDF and MJCF robots with their joints and limits.
Physics	Steps rigid and soft bodies, hinges, motors and contact on the GPU.
Light	Path-traces cameras, with SVGF denoising, and fills depth and other channels for sensors.
Output	Writes video and HDF5 records.
Access	Applies changes to a running world, serves a world over the network, and hosts an MCP server for an AI client.

These parts stay with you:

Part	What you choose
Scale	The voxel size, and how many voxels fit your GPU memory.
Stability	The time step and the stiffness of soft materials. The time step shrinks as voxels get smaller and stiffer.
Bodies	The size of each rigid body. A rigid body under about 30 voxels stalls or jitters, so merge it into its parent.
Control	The signals your program sends each control step, such as a joint target.

Find your page

You want to	Read
See a world on your screen in one sitting	Quick start
Find a scene close to what you want to build	Examples