Troubleshooting

This page covers common issues when using the binary RaiSim distribution.

Executable Not Found

When you build examples from the public raisim2Lib workspace, CMake places them under the build directory:

./build-examples/examples/primitive_grid
./build-examples/examples/rayrai_tcp_viewer

The unpacked package does not include a prebuilt TCP viewer. Build the rayrai_tcp_viewer example target and run it from the build tree. If a command from old docs uses an example_ prefix, check Examples for the current target name.

Missing Shared Libraries

For installed packages and local builds, source the environment script before running examples, rayrai tools, applications, or importing raisimPy:

cd $HOME/raisim2Lib
source ./raisim_env.sh

The script adds both RaiSim and rayrai libraries to the platform loader path. On macOS this is DYLD_LIBRARY_PATH. On Linux this is LD_LIBRARY_PATH. Because this is a per-terminal shell setting, source the script again in every new terminal before starting a viewer, an example, or Python with raisimPy.

Activation Key Not Found

Place the activation key at:

$HOME/.raisim/activation.raisim

or pass an explicit path before creating worlds:

raisim::World::setActivationKey("/absolute/path/to/activation.raisim");

TCP Viewer Does Not Connect

Check these points:

• The simulation must create raisim::RaisimServer and call launchServer.

• The server-based example and TCP viewer must use the same port. The default is 8080.

• Run linux_install.sh, mac_install.sh, or win_install.ps1 after updating the package, then rebuild the examples copy of rayrai_tcp_viewer. A stale viewer source can connect but disagree with the installed rayrai/RaiSim protocol implementation.

For manual RGB/depth cameras, keep the examples-built viewer connected. It renders requested frames and returns them to RaisimServer. If the viewer reports Refusing RGB sensor update without a complete render, rerun the platform install script and rebuild rayrai_tcp_viewer in build-examples; do not launch an older installed viewer binary.

rayrai Window Or Offscreen Context Fails

rayrai requires a working OpenGL 3.3 core-profile context; its context helpers request 4.3 first. On Linux, make sure OpenGL and SDL2 development/runtime packages are available. On headless systems, use the offscreen context helpers documented in rayrai Visualizer and verify that the machine provides a usable software or hardware OpenGL stack.

Vulkan Ray Queries Unavailable

Geometry-traced glass can use Vulkan ray queries on Linux and Windows. If rayrai was built without the optional Vulkan backend, the portable OpenGL tracer remains available. Installing a compiler or driver after a binary package was built does not add the missing backend to that package. Use a package built with Vulkan support or rebuild rayrai from source. A RayraiWindow from a build configured without glslc prints a warning once to standard output with installation and rebuild steps. An existing Vulkan-enabled binary does not need glslc at run time.

For a source build on Ubuntu, install the Vulkan development files and the glslc shader compiler (Python 3 is also required):

sudo apt update
sudo apt install libvulkan-dev glslc
glslc --version

A source build enables the optional Vulkan ray-query backend automatically when these tools are present; RAYRAI_ENABLE_VULKAN_RAY_QUERY defaults to ON. Reconfigure and build after installing glslc:

cmake -S /path/to/raisim-source -B /path/to/existing-build
cmake --build /path/to/existing-build

An existing CMake cache with RAYRAI_ENABLE_VULKAN_RAY_QUERY=OFF keeps that explicit setting; change it to ON when reconfiguring. If tests were enabled in that source build, check the hardware cases with ctest --test-dir /path/to/existing-build -j12 -L hardware-ray-query.

Check for the CMake message optional Vulkan ray queries enabled. A message about portable glass tracing only means the optional backend was not built. The raisim2Lib example build links to a prebuilt rayrai library; configuring that example build cannot change which backend the library contains.

At run time, the active OpenGL device must match a non-CPU Vulkan 1.2 GPU with ray queries, acceleration structures, buffer device addresses, and external memory and semaphore sharing (including the OpenGL FD extensions GL_EXT_memory_object_fd and GL_EXT_semaphore_fd on Linux). On Ubuntu, vulkan-tools provides vulkaninfo for checking the visible Vulkan devices:

sudo apt install vulkan-tools
vulkaninfo --summary

Run the viewer and hardware tests in a graphical session with GPU device access. Containers and sandboxes may hide /dev/dri or NVIDIA device nodes even when the host driver works. If VulkanRayQuery was explicitly selected, an unavailable backend raises an error; Automatic uses the portable tracer when hardware ray queries cannot be used. See PBR materials for these backend settings.

Post-Processing Effect Missing On macOS

macOS provides OpenGL 4.1 with 16 fragment texture units, so rayrai uses its compact PBR programs and the common post-process program there. Effects such as screen-space reflections, volumetric fog, color grading, saturation, and white balance are not applied on macOS; see Platform support for the full list.

Some rayrai examples print the Apple driver message unit 10 GLD_TEXTURE_INDEX_2D is unloadable. No program samples a 2D texture on that unit at those draws, so the message has no visible effect.

First Launch Of An Example Is Slow

rayrai_coacd_mesh_approximation runs CoACD for every mesh on its first run, which can take a few minutes; Ctrl-C stops it during that phase. RaiSim caches the parts beside each mesh, so later runs load them directly. rayrai_forest builds mesh LODs on its first launch and saves them as rayrai_cache_*.lods files beside its assets. Delete these cache files to force regeneration.

Example Asset Missing

Examples expect their bundled assets to stay with the release workspace. If an example cannot find a URDF, mesh, texture, heightmap, or USD asset, verify that the top-level rsc directory exists and that CMake copied it to build-examples/examples/rsc (or build-examples/bin/rsc on Windows).

OpenUSD Runtime Or Plugin Missing

USD mesh loading uses the bundled OpenUSD runtime. Keep the installed openusd directory and USD shared libraries next to the RaiSim binaries: raisim/lib/openusd on Linux, and raisim/bin/openusd plus the usd_*.dll files on Windows.

If an executable is launched from another directory, run the package environment script first so the runtime loader can find RaiSim and OpenUSD. If an OpenUSD runtime is missing from the public package, reinstall or upgrade the matching raisim2Lib release instead of trying to rebuild the closed-source engine.