score:7
You can check if you need a visa using a tool provided by the UK government. If it doesn't ask a question, this is likely because it is not relevant to your requirement for a visa. In this case you almost certainly do require a visa.
Your permenant residency and (presumably) good reasons to return to the Schengen country in question should help improve the liklehood of being granted a visa however.
Upvote:4
No -- having permanent residence (but not citizenship) in another EU country or a Schengen country does not in itself give the holder any right to enter the UK.
... except if you have a residence card that explicitly says it is issued to a "family member of a union/EEA citizen".