I don't use a grid for overland maps, and I don't concern myself overly with scale. I just load it up at whatever the map's default resolution is, and if applicable, I apply the fog-of-war. Then I just guesstimate rate of travel.
To VTT users: How do you handle overland travel? I see a lot of VTT encounter maps, but I'm not sure how to handle the overland. Do you do one grid unit (ie 50/100px) per hour's travel? Per day's travel? Somewhere in the middle? I ask because I'm about to start the region map that will contain all of the PC's overland travel for the forseeable future, and I have no idea what scale to use. We're using MapTool, and have one player remotely playing with us, so all of the maps have to be in MT.
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I don't use a grid for overland maps, and I don't concern myself overly with scale. I just load it up at whatever the map's default resolution is, and if applicable, I apply the fog-of-war. Then I just guesstimate rate of travel.
Bryan Ray, visual effects artist
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Its up to you as a GM to do as much or little overland travel. Just change the scale and use a marker for the party. Drop back to battle map as and when. The scale you choose depends on how far they are going surely. If going by boat then it would be a lot of miles, if on foot for a day or two then a bit less. I always think of it this way - if you were doing this with a whiteboard in a room with people then what would you use ?
also depends on how many rules the GM wishes to incorporate.
sometimes in the past when i ran AD&D games I wouldn't let the players see the overland map, instead They mapped as they traveled while I marked on my map their real location. I'd described the terrain ect as they traveled.
if a players mv was 60'/round (1 round =1min (1-2nd ed)) that is aprox 11miles/16hour travel day on foot. normal maps back then were 10miles/hex so round down to 10 miles 16 hour travel time for setting up camp ect.
this method allows for some great survival sessions. keeping the full real land map from them you can roll a check / day if they go off coarse. you then roll which direction they went off in (percentiles vary per terrains type) you mark on the GM/DM map where they really are(if they are off coarse already then pass a "Lost check" then you can describe that they notice by sun direction or whatever means that they have fallen off coarse.
most settings also have a random wilderness encounter check /per day or whatever depending on the terrain type. if an encounter occurs then they you can have then meet anything from bandits on the road to a wandering dragon.(in those cases I would pull out various battlemaps that match different terrain types to handle the encounter).
this also allows you to require rations and such each day they will use a one day ration from the players supplies.
it is easier than it sounds and can be a lot of fun when getting there is part of the adventure.