I have Houdini Apprentice installed on my Mac running macOS Catalina version 10.15.7 and Houdini 19.5.303 Apprentice My Mac has a NVIDIA GeForce GTX 775M 2 GB gpu.

This is a clean install due to issues with my previous installation. The vellum issue I am still having was present in my old installation of the operating system and I was hoping the fresh install from scratch would rectify the problem.

I believe this is an OpenCL issue so I was wondering if anyone else has come across this issue and if there is a work around to this issue that I could implement?

Below are the error messages I am getting:

Error
Invalid source /obj/geo1/vellumsolver1/dopimport_geometry/load_each_field_end
Error: The sub-network output operator failed to cook: /obj/geo1/vellumsolver1/dopimport_geometry/switch3
Error: Invalid source /obj/geo1/vellumsolver1/dopimport_geometry/load_a_field
Error: vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
vellumobject1 - /obj/geo1/vellumsolver1/dopnet1/vellumsolver1/compute_pressure_vals: OpenCL Exception: clBuildProgram (-11)
-- Too many errors, additional errors were suppressed. --...

Hello!
This happens mainly because either your graphic card's driver is outdated or your graphic card model is outdated at all!
If you want to be able to go further you should set the OpenCL device to use CPU instead of GPU.
To this end you should go to Edit -> Preferences -> Miscellaneous under OpenCL device and set the Type to CPU instead of GPU.

Hi N-G

Thanks for that works a treat now.

Hmmm this is strange, first time in a while I open up Houdini to do some Vellum work and then BAM, as above I'm getting the same problems. Anyone else?

I'm running a 3090RTX and I do have the latest NVidia studio drivers, I wonder if they broke something?

Scott

Just found there was an issue with the same thing in another thread (4090), so it was a driver issue, and using a non-production build of Houdini gets round this particular issue