Limited Line of Sight - Fog of War Revealing

In addition to some tweaks to Fog of War (such as being able to reveal in different shapes and having the reveal/hide options snap to the grid) I'd suggest a selective fog of war. Instead of the GM progressively revealing map, the GM could mark out two levels of FoW - say we call one Shroud which the player cannot see into normally, this represents areas that are normally inaccessible (outside a dungeon's walls for instance) and hidden areas. This looks like normal Fog of War at the moment - totally black. Areas that are accessible but the players have not explored yet are marked with Fog of War. Fog of War appears black when it has not been explored, absolutely clear when in line of sight (which reveals map and tokens in the area) and semi-opaque when not in line of sight (which reveals map but not tokens). Line of sight could be defined by an additional aura quality - players could toggle the ability to see the radius for themselves, but not edit it's size. When the token is moved through fog of war, it becomes revealed automatically. If a character suddenly discovers a secret area, the GM could set the shroud of that area to Fog of War, meaning it could be explored as the token moves into that area. Multiple line-of-sight values might exist (for light and dark, say) and bonuses might be applied if they have items (say, Night Vision Goggles or Torches). Fires in game might increase line-of-sight in straight lines or an area around the source whilst they're within line of sight. Possibly, line of sight could be set to not work "around corners" - if the GM sets the fog of war in lines that run at 90-degrees, the character's line of sight might not penetrate around the entire corner, possibly allowing for some dynamics to it. A final option might be that player tokens could optionally be set to be lost from others without Line of Sight in some areas, representing characters getting lost in the dark or in mist and fog. The whole purpose of it, ultimately, is to facilitate exploration without accidentally revealing too much too soon for the players.

I could definitely use this. I tend to hand draw my maps, so only one of the maps that I'm planning to use in the near future is well-suited to rectangles. That one's easy to reveal as they go, but LOS would make this even easier, since I could just put walls around shapes. (This feature does exist in Maptools, but it's not enough of a dealbreaker for me to go back to MT.)