Examples

Examples are grouped by the feature they demonstrate, with clips recorded from the running programs. Choose a topic, then select an example to open its page; Run explains how to build and run them.

Rendered environments, from minimal scenes to cities, forests, warehouses and off-road terrain.

rayraiOff-Road Buggy

rayraiTank Survival

rayraiCity

rayraiForest

rayraiWater Pond

rayraiWater Stream

rayraiWarehouse

rayraiCity From XML

rayraiForest From .rscene

rayraiComplete Showcase

rayraiBasic Scene

Some clips show third-party models licensed under CC BY 4.0; they are credited in Asset Credits.

Overview

The raisim2Lib distribution ships prebuilt RaiSim and rayrai libraries together with C++ example sources. Build the examples with CMake. The install target does not copy the example executables, and the package does not include a prebuilt TCP viewer: the rayrai_tcp_viewer target builds it from the example sources.

The examples fall into three kinds:

• Server examples, such as primitive_grid, build a raisim::World and publish it through raisim::RaisimServer. View them with rayrai_tcp_viewer.
• Rayrai examples, such as rayrai_pbr_material_grid, render in process with raisin::RayraiWindow.
• Non-visual tools and benchmarks, such as model_asset_pipeline and articulated_system_benchmark, print results or write files.

Together they cover the RaiSim physics APIs, mesh import and export, OpenUSD loading, and rayrai rendering and asset inspection. RaisimUnity and RaisimUnreal are no longer supported; see Legacy Integrations.

For optional manual regression and debug programs, see Regression and Debug Tools.

Run

After the top-level build from Build, Test, and Benchmark, run examples from the build tree:

./build-examples/examples/primitive_grid
./build-examples/examples/rayrai_pbr_material_grid

On Windows, the executables are in build-examples\bin:

.\build-examples\bin\primitive_grid.exe

If the runtime loader cannot find the shared libraries, set up the environment before running examples. On Linux and macOS, raisim_env.sh sets LD_LIBRARY_PATH or DYLD_LIBRARY_PATH:

source /path/to/raisim2Lib/raisim_env.sh

On Windows, CMake copies the runtime DLLs next to the executables. If a DLL is still missing, add the package directories to PATH from PowerShell or from the Command Prompt:

.\raisim_env.ps1

raisim_env.bat

Visualization modes

There are two visualization paths. See Visualization for the full workflow comparison.

RaisimServer examples

Server examples such as primitive_grid create a RaiSim world and publish it through raisim::RaisimServer. They do not open a renderer window themselves. Start the source-built viewer, then run the server example:

# Terminal 1
./build-examples/examples/rayrai_tcp_viewer

# Terminal 2
./build-examples/examples/primitive_grid

The default server port is 8080 unless the example changes it. Use this path when you want to inspect the same simulation data that a normal RaisimServer application publishes.

Rayrai examples

Examples such as rayrai_pbr_material_grid, rayrai_pbr_texture_maps, and rayrai_visual_asset_support create or use a raisin::RayraiWindow directly and render in process. They do not need the TCP viewer:

./build-examples/examples/rayrai_pbr_material_grid

Prefer these examples when you need camera images, GPU/offscreen rendering, PBR materials, glTF visual import, or standalone rayrai feature inspection. USD visual meshes can also be loaded through RayraiWindow::addVisualMesh; see OpenUSD Loading for the importer scope.

Non-visual examples

Some examples print output or create files instead of showing a window. model_asset_pipeline writes preprocessed and exported OBJ files to raisim_model_asset_pipeline_example in the system temporary directory (/tmp on Linux). articulated_system_benchmark and anymal_standing_benchmark print timing results.

Example layout

The examples project groups targets by executable behavior:

Group	Purpose
Server examples	RaiSim physics, contact, terrain, sensor, robot, XML/MJCF, and OpenUSD scene workflows published through RaisimServer.
rayrai_*	In-process rayrai renderer examples and the rayrai_tcp_viewer tool.
Benchmark examples	Timing runs for articulated-system, contact, and sleeping-island workloads.

Choosing an example

Start with these targets when learning a specific feature:

Target	Demonstrates
primitive_grid	Basic rigid primitive creation and RaisimServer publishing.
model_asset_pipeline	Mesh preprocessing, content-hash cache reuse, addMesh with processed assets, and OBJ export from a world.
shadow_hand_usd_cube	Loading an OpenUSD ShadowHand scene through World(shadow_hand.usd), adding a native RaiSim cube, and publishing both through RaisimServer.
nvidia_usd_robots	Loading vetted NVIDIA Isaac Sim robot USD files with World::addUsdArticulatedSystem and publishing them through RaisimServer.
rayrai_pbr_material_grid	Inspecting metallic-roughness PBR material behavior under rayrai.
rayrai_visual_asset_support	Rendering textured URDF visual meshes (OBJ/DAE with image textures) separately from their collision geometry.
rayrai_coacd_mesh_approximation	Visually comparing original meshes and CoACD convex approximation parts generated through World::addMesh. The first run can take a few minutes while CoACD generates and caches the parts.
rayrai_tcp_viewer	The TCP visualizer used by RaisimServer examples.
tendon_elastic, tendon_pulleys, tendon_coupling	Elastic suspensions, routed guides/pulley branches, and joint transmissions. See Tendon examples and Rayrai.
rayrai_tendons	Automatic tendon rendering with scene selection, pause/step/reset, and live transmission values. See Tendons.
rayrai_inverse_kinematics	Mouse-driven inverse kinematics: drag and turn a target, and ArticulatedSystem::solveIK() drives a simulated Kinova arm with a Robotiq gripper after it, through joint PD targets, to push, grasp and lift cubes. See Rayrai Example: Inverse Kinematics.
robotiq_cloth_fold	A Kinova arm with a Robotiq 2F-85 lays a cloth on the table and folds it in half: deformable cloth in contact with gripper pads, a table and itself, and fold waypoints solved with ArticulatedSystem::solveIK() from where the cloth landed. See Server Example: Robotiq Cloth Fold.
heavy_objects_on_cloth	A 10 kg ball on a cloth, a 5 kg box on two stacked cloths, and a 5 kg blanket over a 1 kg box, with the cloth solved together with the bodies, so each load rests on what carries the cloth. See Server Example: Heavy Objects on Cloth.
cloth_on_slope	A box on a cloth on two ramps: below the friction angle both stay, above it they slide together. See Server Example: Cloth on a Slope.
tablecloth_pull	The tablecloth trick: a sharp pull whips a cloth out from under three dishes, which stay on the table. See Server Example: Tablecloth Pull.
rayrai_deformable_terrain	An off-road buggy drives across deformable soil, leaving permanent wheel ruts. See Rayrai Example: Deformable Terrain.
rayrai_motor_operating_region	Actuators with motor operating regions (EM-MOR), linked from the URDF as actuator files, with live torque-speed plots for the twelve motors of a randomly actuated quadruped rig. See Rayrai Example: Motor Operating Region.
rayrai_forest	Dense instanced vegetation on a heightmap with automatic mesh LOD, foliage wind and shadows, and asynchronous loading. See Rayrai Example: Forest for the required rayrai version.
rayrai_forest_from_rscene	The same forest built from its saved RaiSim Engine .rscene file with raisim::World(path) and shown by a RayraiWindow. Requires RaiSim and rayrai v2.8.2 (not yet released); see Rayrai Example: Forest From .rscene and .rscene File.
rayrai_city	A photoreal city of modular buildings, streets and parked cars loaded from rsc/city/rayrai_city.rscene, with an ANYmal C quadruped added in C++. See Rayrai Example: City.
rayrai_city_from_xml	The same city and robot from one RaiSim XML world file, which describes the ANYmal C and includes the city's .rscene file. See Rayrai Example: City From XML.
rayrai_warehouse	A photoreal warehouse of pallet racks, forklifts and a dock area loaded from rsc/warehouse/rayrai_warehouse.rscene, with an ANYmal C quadruped added in C++. See Rayrai Example: Warehouse.
rayrai_water_pond	A pond in a meadow drawn with rayrai water: ripples, the sun glittering on the surface, reflections of the banks and a green tint that hides the floor with depth, with grass, trees, rocks and a wooden jetty on its banks. See Rayrai Example: Water Pond.
rayrai_water_stream	A creek running down a hillside into a pool, simulated as shallow water on the GPU: the water parts around mossy rocks, foams where it runs fast and fills the pool, and wooden balls ride the current with buoyancy and drag from sampleWaterFlow(). See Rayrai Example: Water Stream.
rayrai_offroad_buggy	An off-road buggy with double-wishbone suspension, coilovers and rack-and-pinion steering, all in one URDF closed by pin, equality and mimic constraints, driven with the arrow keys on a dirt race circuit with pits, tyre walls, hay bales, cones and spectator stands; --validate checks its physics. See Rayrai Example: Off-Road Buggy.

Targets without a dedicated page

These targets are built with the others but are documented only here or on a feature page:

Target	Demonstrates
heightmap_mesh_drop	Twenty monkey meshes with triangle-mesh collision dropped one at a time onto a colored procedural heightmap.
blocky_heightmap_drop	900 primitives and convex-hull meshes dropped onto a heightmap made of flat 0.4 m tiles.
large_scale_ray_test	Repeated ray queries against walls and pillars; see Ray Test.
rayrai_blue_wall_scene	An authored glTF interior with its light sidecar and HDR environment, described by rsc/rayrai/blue_wall/blue_wall.rscene. The example reads that file with its own parser; raisim::World(path) and a RayraiWindow on that world load it as well (see .rscene File). --screenshot PNG renders in a hidden window, saves the image, and exits.

Runtime assets

Some targets depend on bundled assets or platform runtime packages:

• OpenUSD loading uses the package's bundled OpenUSD runtime and USD files; keep the openusd runtime directory and rsc assets with the installed package.
• Rayrai examples require SDL2/OpenGL and rayrai runtime libraries. See Platform support for the OpenGL requirements and the reduced macOS feature set.
• Poly Haven and PBR asset examples require the corresponding assets under rsc. CMake copies rsc next to the executables (build-examples/examples/rsc, or build-examples/bin/rsc on Windows).
• rayrai_forest reads its assets from rsc/forest in the configured checkout and writes regenerable rayrai_cache_*.lods files beside them. rayrai_forest_from_rscene reads rsc/forest/rayrai_forest.rscene from the rsc copy next to the executables, and the scene references the same assets.
• rayrai_city reads rsc/city/rayrai_city.rscene from the rsc copy next to the executables (--scene picks another file). Its street trees are the forest's, so it also needs rsc/forest. rayrai_city_from_xml reads rsc/xmlScripts/rscene/anymal_in_city.xml, which includes the same scene.
• rayrai_warehouse reads rsc/warehouse/rayrai_warehouse.rscene the same way. It reuses the city's sky, asphalt and traffic cones, so it also needs rsc/city.
• rayrai_offroad_buggy reads rsc/offroad_buggy (the car, its URDF, the terrain and the race venue's props), places the trees, rocks and grass of rsc/forest, and uses the sky and cars of rsc/city and the barrels of rsc/warehouse.
• rayrai_water_pond places the plants and rocks of rsc/forest.
• rayrai_water_stream places the plants and rocks of rsc/forest and gives the rocks in the creek colliders from the same models.
• rayrai_coacd_mesh_approximation writes raisim_coacd_* cache files beside the YCB meshes in the build tree's rsc copy.

After building, list the example executables from the platform-specific output directory. Linux and macOS builds place them under examples:

ls build-examples/examples/

Windows builds place them under bin:

Get-ChildItem .\build-examples\bin\*.exe