Attempt to change a single parameter. Not all backends and parameter types
support all kinds of changes.
@param ctx a valid render context
@param param the parameter type and data that should be set
@return error code. If a parameter could actually be changed, this returns
success, otherwise an error code depending on the parameter type
and situation.
Attempt to change a single parameter. Not all backends and parameter types support all kinds of changes.
@param ctx a valid render context @param param the parameter type and data that should be set @return error code. If a parameter could actually be changed, this returns success, otherwise an error code depending on the parameter type and situation.