I've had several requests for details about a digital map projection setup I described in this letter, published in Dungeon magazine #113:
My gaming group uses a rather high-end mapping setup that has a profound impact on our level of enjoyment of the game. In fact, if for some reason we cannot use the setup, my spoiled gamers want to re-schedule the game session. Let me describe it…
I scan in adventure maps and Photoshop out all for the DM-only information (room numbers, secret doors, traps, etc.) and create a mask layer. We then suspend a digital projector (connected to my laptop) from the ceiling, pointing directly at the game table. I project the edited map onto the game table and scale it to match our miniatures. As the players explore the map, I erase portions of the mask layer, revealing the map beneath.
As you can imagine, this has really improved the gaming experience. We now have a visually appealing map to represent the adventuring environment, and the game-time consuming task of drawing a map is drastically reduced.
There are of course drawbacks.
1) Cost. The equipment and software necessary for this setup are beyond many gamers' means.
2) The task of scanning and editing printed maps is labor and skill intensive.
My hope is that you could help me and any others that wish to use this technique by publishing this letter or similar instructions and by making high-resolution maps, which do not contain DM-only information, available for download.
If you have any questions or comments about digital map projection, please join in on our bulletin boards. You'll also find links to other discussion threads on other bulletin boards there.
The photographs below don't really do justice to the appearance of the projected map. They are clear and colorful in when you view them in person.
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The Gaming LoungeOur gaming area is in the basement. This made mounting the projector a lot less intrusive than if it were in a main living area. I don't think my wife would have been to keen on me hanging it from our dining room ceiling. |
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The Game TableHalf of the game table has a dry-erase grid glued to it. We use a piece of foam core as a nice surface for map projection. The projector is about 5 ft. from the table surface. |
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Our projector rigI purchased a used Infocus 425z projector from eBay for $500. I've seen the same projector sell for as little as $270 recently. It took us only a half-hour to mount it using some weather stripping, a few screws, a hook, and a chain. |
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Laptop = DM ScreenI keep a spreadsheet open on my laptop to keep track of combat, NPCs, character wealth, spell effects, etc. Of course I use this site as a quick rules reference. The map is projected from the same laptop via monitor spanning. Here's a screenshot of both screens. |
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ScalingI create a 24 square rectangle in my map image to use as a scaling reference. As you can see this map is very high resolution to begin with. |
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ScaledThrough trial and error, I then resize the map image until the 24 square long rectangle is 24 inches long. For this map, the magic number was 36.7% of the original size. |
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Entering The MapI begin the map with as much or as little revealed as is appropriate. I find that the compass (showing north) and map scale (1 square = 10 ft. in this example) info is helpful to players. |
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Exploration beginsI use the eraser tool (the circle in the picture is the eraser cursor) to reveal line of sight map info. For small areas, I do this freehand. |
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The Map Takes ShapeAs the adventurers explore, more of the map is revealed. This lucky rogue has Goggles of Night, allowing him to see 60 ft. into what appears to be a large room. |
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Avert Your Eyes!When I have to reveal larger or more complex areas of the map, I have the players look away and I reduce the opacity of the mask layer. This allows me to see the map below and quickly edit the mask layer. Here I'm revealing a whole room by selecting it with the marquee tool. |
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Now You Don't See It…Our trusty rogue explores what appears to be an empty hallway. |
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Now You Do!A couple of successful search checks later, and I reveal some map features. The secret door and trap shown here are on separate layers that I show when they are discovered. You can show nice spell effects using layers also. |