By default the Arnold render engine or htoa is not enabled on Monty computers. In order to enable it you need to make some changes to your houdini.env file located in the /home/”username”/”houdini version” directory.

  1. Add the path to the htoa plugin to your HOUDINI_PATH variable.
    • HOUDINI_PATH=”/opt/htoa/htoa-6.2.2.1_r0a87540_houdini-19.5.640/htoa-6.2.2.1_r0a87540_houdini-19.5.640;&”
  2. Set the arnold data collection check to disabled.
    • ARNOLD_ADP_DISABLE=1
  3. Add the path to the htoa OCIO config.
    • OCIO=”/opt/htoa/htoa-6.2.2.1_r0a87540_houdini-19.5.640/htoa-6.2.2.1_r0a87540_houdini-19.5.640/scripts/ocio/configs/arnold/config.ocio”

I have attached a env file that will enable htoa while still keeping Redshift as a render option. To use it replace the existing houdini.env file on a monty computer with this one before opening Houdini.