NewbieDM Tutorial: The Battlemap Part III

Posted on November 17, 2009 by


Here is the last part of the battlemap tutorials for, written by professional cartographer Jonathan Roberts.  Click here for part 1, and here for part 2.

At the end of the last tutorial we had a lovely map, though it’s a little bare. In this tutorial I’ll cover the little tweaks that will finish off the map and how to present the finished product.

Final touches to the terrain – lava!

Here I will cover how I went about creating the lava, and discuss some alternative approaches to the one I took.

Now I already have the lava lines drawn in, so as with my walls, I can create a selection by using the Fuzzy Select tool. I then use Select->Grow to expand it by 2 pixels so that it runs along the center of my lines rather than along the edge. Now I hit Select->Save to Channel to save the selection for future use. With this in place I can quickly lay in some colours.

I create a new transparent layer and fill it with a dark red (7f1800 in html notation for anyone that wants to re-use it). I now have a totally red map. Once again I right click the layer and add a layer mask, being careful to pick my lava selection. Now I only have red lava, but it’s still a little extreme. As before I soften this by duplicating the layer, setting one layer to soft light .

Now that looks good, though it looks a little more like rivers of blood than lava. From looking at some useful reference photos of lava from Google it’s clear that the defining feature of lava is the sharp bright line – almost like ripples. So I take a new layer, grab a nice bright yellow and the ink tool and start detailing the lava. It takes a while to place all the ripples, but it’s starting to look more like lava.

Currently it’s a bit harsh – and certainly not subtle. Now lava is bright because it’s giving off heat – so we should expect these bright regions to give off light. So I duplicated the layer and used the Gaussian Blur filter: Filters->Blur->Gaussian Blur… This adds a subtle glow to the lines.

I’ve also dropped the opacity of the hard highlights to 60% to avoid the harsh look that we had at the start.

Now each sharp line gives off light, but the whole pools of lava give off light too. To add to this effect I add a new layer, set it to soft light and use a very light yellow to lay in the light given off by the lava.

Now that’s quite a lot of trouble to get detail into the map, especially drawing in all the lines in for the lava. One workaround is to find a
texture that you can use to add detail. An excellent place to look is Here you’ll find a lot of good textures.
For this example I’ve taken the image that can be found here.

I placed this on a new layer, making sure that it covers all the lava:

Now obviously the marble doesn’t look convincing at is, but the pattern of light and shade looks like it might work well. I then set this whole layer to soft light and voila! – instant lava.

This works particularly well because the marble texture is almost greyscale. Had it been brightly coloured it would be best to desaturate it first (Colours->Desaturate).  You can use this technique to quickly add some interest to regions and delineate different types of terrain. It’s easy to overdo this, so drop the opacity low to start and then slowly build it up.

Remember that the more subtle layers you pile on top of each the better the final result will look.  We’ll cover more of this when dealing with regional and city maps.

Adding set dressing

Okay, so now we have a map with all our different features and terrain in place. Time to add some set dressing. There are two ways to go about this. Firstly, we can draw our items of set dressing ourselves. The alternative is to find some items drawn by someone else and steal them.  Remarkably, this second approach is perfectly legal as long as the person has made them freely available. There are loads of items that fall into this category in the User Creation Forums over on the Dunjinni website ( I’ve also got a pack of items on my website that you are free to download and place.

For my example map I used torches, braziers and doors from the map pack, as well as some bones to give a properly ominous air to the
sacrificial pillar.  The rope bridge and the pile of dragon gold I created from scratch for this map. The process for these is the same as for other features of the map. Add a new layer and draw in the lines with the ink tool. Create a new layer for the colours. Finally add a soft light layer to add light and shade.

Here’s the progress of the rope bridge through this process. In the last step I added some extra shadows beneath the bridge to emphasise the height from the floor of the cavern.

Now to add some torches to light the caverns (lifted from my map pack):

A side view to help the GM:

and a signature! Don’t forget to leave your mark on your map. It’s good to see it there, and it also means that if you put it up on the web for others to use that people know it’s yours.

Oh, one final edit. I duplicate the grid layer and blurred one of them slightly. This is helpful because if you are looking at a map at different scales (say in a virtual tabletop where you can zoom in or out) then the program that does the scaling can easily lose a 1 pixel wide line. It just averages the pixels out and gets rid of the line. This doesn’t happen to the gently blurred line – so you have a smooth transition as you zoom out rather than getting a jagged effect with bits of grid disappearing in chunks as you zoom out.

With that final tip we are finished:’

Make sure that you keep all these features on their own layer, I’ll explain why when we get to showing off your map using a virtual tabletop.

Showing off your map

Now all of this is a little overkill if all you want to do is keep the map to yourself and draw the combat encounters out on a dry erase battlemat.

So how do you go about getting this map in front of your players? Well there are two ways to do it.

1. Printing it out.

It’s perfectly possible to print out your map and use it at the table. If you’re feeling flush you can take it to your local print shop and have them run it off on a large format printer. There are even dedicated online printers that specialise in RPG battlemaps ( However if you want to print it at home you certainly can.
First of all, make sure that your map is scaled to the correct size. Here I’ve got a 100px grid, so I need to set the resolution to 100dpi to make sure it prints out 1 inch squares. This can be set through Image->Scale Image…

Now make sure that you turn off any images that you don’t want your players to see. Hide the secret doors, remove the traps. In this case I’m going to turn off all the elevation text. Now save the map as a jpg. To do this go to File->Save As… and save it out as something like MapFinal.jpg. It will ask you to set a quality. 85% should be fine so just click okay.

Now you need to download a wonderful little program called Posterazor.  It’s free and cross platform and you can get it here.  Load it up. This program slices up an image – without rescaling it – into a multi-page pdf. Once it has done this, you can print out your map page by page. Not only does this allow you to print the map yourself, it also
means that you can keep most of the map a secret from your players before they explore it.

When you start the program you’ll be asked to load an input image.  Load up your MapFinal.jpg and make sure it’s got the right dpi setting.  As long as you scaled your image right this should be fine. On the second page make sure you have the correct type of paper selected.  Letter for the US, A4 for the UK, just check that your printer has the paper that you pick. Next comes the overlap. This sets the amount of overlap between images on each page. You can have as little or as much as you like. It’s worth having a little as it helps line things up at the table. In step 4 you’ll see an image of your map with red lines over it.  This shows you where the program is going to cut your map. You can edit the values on this page to move the cuts around, but it’s usually pretty good. Finally on step 5 you can save out your pdf. You’re done!

Open your pdf, print it out and take it to the gaming table. You’re all set to use your glorious creation for your game.  For those who would like to save ink, you can also do this at the end of stage 1 – when you have black and white map with a simple grid. This gives you all the same play value, without costing you a fortune in colour cartridges.

2. Using a virtual tabletop

The alternative, and one that uses no ink at all, is to use one of the growing number of virtual tabletop programs out there. I personally have used maptool ( ever since I moved country and wanted to keep my old game going. I now use it both with my friends from the UK, and also for a face to face game in the States.  Preparing the image for use in a virtual tabletop is much the same as
preparing it for use in Posterazor. Remove all GM only information – remember you’re showing the players the map. Now save it out as a jpg.  Before you saved it at a high quality. Now when the Save As JPEG dialogue comes up, click the Show Preview In Image Window checkbox.  This will give you an estimate of the filesize. As you move the quality slider you’ll see how this size changes.

Now this is a fine balance. Too low a quality and you’re map will look rough and have obvious compression defects. Too high a quality and you’ll be trying to upload a 10MB file to all your friends at once. Now your internet connection may have a great download speed, but I’ll bet it will take a while to upload 50MB. So strike a balance. If you’re using it for a face to face game then you don’t need to worry about internet speeds and you can go with a high quality that looks good.

Finally, depending on the virtual tabletop program, you may want to use a version of the map without the set dressing and add those items, such as the torches and braziers, in the program itself. Now you see why I said you might want to keep those on their own layer! Equally, maptool has an inbuilt grid, so I use a version of the map without a grid, and let maptool keep track of the distances.

With a little set-up for the light and shade, and with a top down token from the wonderful tokens of Devin Night of the Four Ugly Monsters the dungeon is ready for use face to face (with a second monitor, a player laptop or a projector) or across the world.

Here I set up the light sources to conform to the light rules and told maptool where the walls were. I also made sure that the elevations were only visible to the GM – so they can quickly see all the relevant information, but it doesn’t break the suspension of disbelief for the

Now doesn’t that look better than a dry erase battlemat with markers?  And all for the price of two free pieces of software and a small investment of time.

If you want to have a look at the full blown maptool campaign file it’s included in the RPGNow download. In fact there are two campaign files in there – one for Pathfinder/OGL lighting rules and another for 4th edition rules.
If you’d like to see this process in real time, then sign up to The Breaking of Forstor Nagar – a patronage project with Rite Publishing. As
a patron you’ll be directly involved in the development of the adventure with input at every stage. This includes map design, storylines, NPCs and encounters. If you’d like to find out more, visit The Breaking of Forstor Nagar and get involved.

I hope you’ve enjoyed the first mapping tutorial. I’ll be interested to see what people create! I’ll be back in due course with similar tutorials for some larger scale maps, dealing with towns, regions and perhaps even whole worlds. Until next time, happy mapping!

Well, there it is guys.  One of my goals for the site has come true.  A kick ass mapping tutorial by a professional.  I can’t thank Jonathan enough for this series.  Based on the number of messages I’ve received about it, I know it’s destined to become a popular feature here (if it isn’t already).  We have other tutorials coming down the pipe, but let’s give Jonathan’s photoshop some cool-down time!  Make sure you visit his website at Fantastic Maps, for more mapping goodness, and if you have made some maps following the tutorials, share them with the rest of us!