BaraCuda : a CUDA kernel compositor

baracuda is a POC/WIP of a kernel composition utility, meant to break down the writing of cuda kernel into smaller pieces and examinate the rendering result of the combinations in realtime.

It’s written with QT5 and runs with cuda v4 to v7.

GLSL sauce

A GLSL wrapper is included : with a few modifications, a GLSL code will compile. Not all, as the wrapper is fairly incomplete.

Don’t expect performances : this does not generate machine code, but add extra structures, for the standard glsl functions, swizzles operations and vectors association/composition to work.

Build

$ qmake && make note that if you qmake -project, this will overwrite baracuda.pro

cuda setup

Check the hardware

lspci -v | grep -i nvidia

If your card is registred as a 3D controller, you’ll need either to run bumblebee, or to turn the GPU as primary device in your BIOS.

check the number id and go to supportedchips

For debian : https://wiki.debian.org/NvidiaGraphicsDrivers

Bumblebee project page : https://wiki.archlinux.org/index.php/bumblebee

For a fresh start on debian :

purge anything related to nvidia and cuda : apt-get purge nvidia-* cuda-*

install nvidia-driver through the jessie backport : apt-get install -t jessie-backports bumblebee-nvidia

Inspect any errors by digging into /var/log/Xorg.8.log and kern.log

gcc setup

take note that gcc-4.7 and up aren’t supported with cuda6 you’ll have to install gcc-4.6 g++-4.6 (or 4.4 with cuda5)

troubleshoot

CUDA_ERROR_NO_DEVICE (no CUDA-capable devices were detected) cuInit returned 100 either you’re back to start or you forgot to run baracuda with optirun baracuda

If running the rendering in a virtual framebuffer and that is the case with optirun – libqxcb will crash when dragging an item from the list to composer. For now, the workaround is to add the item when it’s clicked

CUDA_ERROR_INVALID_CONTEXT This most frequently indicates that there is no context bound to the current thread. This can also be returned if the context passed to an API call is not a valid handle (such as a context that has had cuCtxDestroy() invoked on it).

This can happen if you mix different API versions too (i.e. 3010 context with 3020 API calls). See cuCtxGetApiVersion() for more details.