[major] Detect Monsters spell @ "L"

[tangar]

Detect Monsters Detects all non-invisible monsters nearby. (project)
Required skill level for first spell level: 3.

I play without "big map" option and I need to "L" a lot (move my view between map sectors). Problem is that spell "detect monsters" dissapear when I move screen with "L". It makes quite bad playing experience cause I play without big_map and need to move my view around a lot.

Possible solutions:
1) the most obvious - save detected items when you move screen
2) add possibility to cast spells in "L"-mode. Then you could move map around and recast spell
3) ... add your ideas