glsl/st: vectorise interfaces of SSO shader programs
For example the SSO program may consist of just tcs -> gs or even just a vs. In these case we want to vectorise the externally facing shader interfaces just like we would in no SSO programs.
Due to an influx of spam, we have had to impose restrictions on new accounts. Please see this wiki page for instructions on how to get full permissions. Sorry for the inconvenience.
For example the SSO program may consist of just tcs -> gs or even just a vs. In these case we want to vectorise the externally facing shader interfaces just like we would in no SSO programs.