[Award Winner] Drawing hand drawn maps in Gimp

[torstan]

Multiply is also really useful if you want to use a reference drawing. So for example say you found a map on google of a region you wanted to turn into a hand drawn map. Copy that image to your computer. Open up your parchment image as above. Open up the Google image and scale it so it will fit nicely over your parchment layer. Create a new layer over your parchment layer and paste the Google image on to it:



This gives you something like this. Now change the Layer mode to multiply and you get something like this:



Now create a new transparent layer (remember shift-click), choose the ink tool and start tracing round the coastline, along roads and so on until you have a line drawing of the map you are after. This way you need never complain of lack of hand-drawing skills or inspiration again!

Now that we have got our ink lines by subterfuge, deceit or elbow grease, we'll move on to colouring the image tomorrow.

[torstan]

Okay, now that we have our lines, we need to get some colour down. In this case there are four different coloured areas - the sea, the deck, the sails and the rocks. First things first - create four new transparent layers and name them for the colours they will hold.

We'll start with the sea colours. We could just do a block fill of a nice sea colour to start with, but that's a bit dull. It's more interesting if we can get a bit of variation in the colour for the sea, so we will build it up bit by bit.

For varying colours I find it useful to use the airbrush with the 'Use colour from gradient' switch turned on. Gimp comes with a deep-sea gradient so that seemed particularly appropriate for this case but you can use others, or make your own. In this case I use the following settings:



Now take a large fuzzy brush and block in the sea with colour. Note that I have scaled up the brush to aid in quickly filling a large area. Don't worry if it's not smooth at this stage. We'll deal with that in a minute. Also, don't worry if the colours aren't quite right. They are just going to give us a starting point. Finally, the edges are also not a great problem. It is more important to get the colour up to the edges of the area you are filling in than worry about going over into the adjoining area.

The end result will look blotchy and non-too smooth. Switch from the airbrush tool to the smudge tool. Now I decided that I wanted it to look as if the waves were rolling in from the north-east. Therefore I use the smudge tool to blur the colours in lines from north-west to south-east. Here is a screenshot of the smoothing in progress. Note that the area in the bottom right of the image has not been smoothed yet.



Notice how the colour variation smooths out to give the impression of waves. Now this still looks a bit lurid. I'll deal with that next.

[RobA]

---Useful tangent---
Note that shift-clicking the new layer button in the layers dialogue creates a new layer with the last used values. This saves ages when creating lots of new layers like we will be doing here.
---end of tangent

I'd rep you for that if I could... never knew that one! Thanks

-Rob A>

[torstan]

Very glad to be of use. Sounds like you need to spread the love around a bit. Find some maps to rep and come back!

Okay, a bit more after a holiday sailing on the Mazurian Lakes. Yes, I like boats in RL too.

After using the smudge tool over the bluey green sea colours I ended up with this result:



Now this is pretty lurid and not at all a reasonable sea colour, let alone a nice wash colour over a parchment background. To get that we only need to change the layer mode from normal to overlay and, viola, we get a great faded wash over the sea area.



However this is clearly not there yet. This gives us a dappled blue and green base, but we need a darker blue background for the sea.

[torstan]

-------- Another small tangent ---------

A few handy viewing tips in Gimp to help with getting a decent view of your image.

• ctrl-shift-e maximises the image to fit within the window you have open, such as in the second image above.
• 1 - pressing 1 will get you to 100% zoom.
• F11 - toggles full-screen. You can then use ctrl-shift-e or 1 to see your image at a large scale within full-screen.

-------- end of tangent -------

Now we want to get a nice dark blue for the sea to give it a deep-sea look. For this map I used the City Colours palette provided by Rob over in his Mapping a Region in Gimp tutorial. I used the dark blue with the airbrush tool and a large fuzzy brush (remember to uncheck use-colour-from-gradient) to block in the dark blue sea. Again, don't worry too much about edges, we'll deal with them soon enough. After blocking in the colour, use the smudge tool to smooth out any obvious edges and get a relatively smooth finish. Here's a screenshot with the colour laid down and the other sea-colour layer turned off:



Now, we have no interest in having block colour on the map. The idea is to let the variation of the paper texture beneath show through to give texture to the whole image. No surprises then that we want to switch the layer type to overlay again. With the other sea colour layer turned off (note there is no eye icon beside the other sea colour layer on the left) this looks like:



With both overlay layer's switched on we get:



This is starting to look like a dark storm tossed sea,but we could still do with going darker. We could duplicate the dark blue overlay layer to darken it further, but in this case I decided to go with a burn layer instead.

I duplicated the dark-blue overlay layer and switched the layer mode to burn. This makes everything very dark so I reduced the opacity to 20%. This gives the result:



This is pretty close to what I want for my sea colours now.

So the basic method for colouring in these maps takes the form:

1. Block in the colour with a large fuzzy brush. If you want some colour variation use a good gradient of colours and check Use-colour-from-gradient.
2. Use the smudge tool to smooth out the obvious edges.
3. Set the layer to overlay
4. Experiment with duplicating the layer and using other layer modes for the second layer - possibly burn for a dark, moody edge, or normal with low opacity to bring up the colours.

Next I'll make good my promise of dealing with the edges that I coloured over.

[torstan]

Okay, after a bit of an extended break here's the next step. Currently the coloured layer for the sea bleeds over - a lot - into the areas that we don't want to be sea coloured. The plan is to clean up those edges. There are a few ways to do this. Firstly there is the obvious choice - take the eraser tool and go round the edges - yes it's that easy.

However, we have a number of sea colour layers, and it's going to take a while to go over all the edges for each one. Not only that, but we may well erase something we actually wanted to keep. The best way to deal with this is using layer masks.

1. Open a new layer (shift-click the new layer buttin to open a new transparent layer as before).
2. Take a hard edged black brush.
3. Turn off the pressure sensitivity to opacity if you are using a tablet.
4. Colour black all areas that aren't going to be covered by the sea colours.
5. Name the layer Mask.

You should now have an image that looks something like this:



Don't worry that you are drawing heavy black lines over your beautiful creation, they won't be there for long. This step takes a little time, but it will save time in the long run.

1. Make the Mask layer invisible so that you don't see the large black image messing up your image.
2. Go to one of your sea colour layers, right-click -> Add layer mask. Accept the default setting of white (full opacity).
3. Go back to your black Mask layer.
4. Select all (ctrl-A) and copy (ctrl-C).
5. Select the white layer mask you created at step 1 by going to the layers dialogue and clicking on the white box that is beside the thumbnail of your colour layer.
6. Paste (ctrl-V) the black image of your non-sea area. As the layer mask (rather than the image) was selected, you won't drop a large black blob over your map. Instead the black lands on the layer mask. Click the anchor button at the bottom of the layers dialogue to anchor the pasted layer to the layer mask.

You should now have nice sharp edges on your colour layer rather than the spread of colour over the lines. You can repeat the process for all the other colour layers you used to give yourself a nice sharp edge throughout.

Now the layer mask is useful for the sea, but it is also useful for the other areas. Go to a new area - say the deck colours that currently is empty.

1. Right click the layer -> Add layer mask... and keep the white(full opacity) setting as before
2. Paste the Mask image on to this layer as before.
3. With the layer mask still selected go to Colour->Invert

Now the layer mask is the mirror image of the sea colour mask. This means that any colours you lay down for the deck will run up to precisely the edge of the sea colours and no further. This saves a lot of eraser work later.

This should give you something like the following:

[torstan]

--- Detour ---

This is a very basic use of layer masks. They are incredibly useful. For those who want to play a bit more, consider the following extensions:

1. Not just black and white
Obviously we use the layer masks above to get a hard edge between colours. However there are some areas in which we might want some colour bleed. For example I may not want the sea colour to be so dark over the submerged sails. To do this:
1. Take the airbrush tool and set the ink colour to black.
2. Select the layer mask of the layer you want to lighten.
3. Gently paint in the area you want to lighten.

Don't worry if the colour disappears a little too fast. You can always darken it back down by switching the airbrush to white and painting over the area again. Smooth out any hard edges with the smudge tool until you are happy with the results. To see what you've done, go to the layer and right-click->Show Layer Mask. This will let you see the greyscale layer mask directly. You should have a blurred area in the region you have just been painting.

Note for layer masks white corresponds to full opacity for the corresponding layer, whereas black is full transparency (it won't show up). Therefore a 50% grey on a layer mask means the corresponding region of the layer will only show at 50% opacity.

So for the water mask I could use the following mask. This would mean that the sea colour layers are less opaque over the sail area, least of all over the edges of the sails that are towards the surface.



2. More than one masked region
Here I have created a mask for just one region - sea and not sea. That's pretty reasonable as the image actually has very few areas of colour in it. In a more complex image it may well be a good idea to create a black mask image (such as the Mask layer used above) for a number of different areas of colour. In this example I should probably have created a separate mask image for the sails and for the deck. This is easy to do. If you create a separate black image covering each of your major areas of colour, all you need to do to create the relevant layer mask is to copy and paste each mask you want for your layer to the layer mask. In each case the relevant mask will be some combination of the mask images you have drawn.

In the case of this map it would go like this. I would draw one Mask layer for the woodwork - deck, masts, boom and so on - one for the sails and one for the rocks. Now the sea is different from all of those. Therefore to build up my sea mask I would create a new white sea layer mask. I would then paste a copy of each of the Deck Mask, Rock Mask and Sail Mask on to the sea layer mask. When I do the deck it is actually much easier. Add a white layer mask to your Deck Colours layer. Copy and paste the black Deck Mask image to the layer mask. Click on the layer mask and go to Colour->Invert. Voila, a deck colour layer that will keep your colouring within the lines.

--- End of Detour ---

[RobA]

Here is another gimp tip for you (discovered when hand drawing my novel map in gimp) that has become something I can't work without...

When in the full screen (f11) you have no tool palettes showing. Hitting the tab key twice brings up all the palettes, which stay up until you go back to working on the drawing, at which point they drop below again.

-Rob A>

[torstan]

Right, now that we have the layer masks sorted, there is no reason not to colour the new regions in just the same was as we did with the sea. Remember:

1. Lay down areas of colour with the airbrush and a large fuzzy brush
2. Use a gradient of colours if you want some colour variation across the area
3. Smooth out any lines using the smudge tool
4. Duplicate the layer, keep one as a low opacity layer with a normal blend mode and the other as a low opacity layer with overlay, soft light or multiply blend mode. Play with the different modes and opacities until you get an effect you like. Also remember you can lighten/darken a layer and change it's whole set of colour values using the dialogue in Colour->Hue/saturation...

Do this for all of your regions of colour to get a result that looks something like this:

[torstan]

RobA - thanks a lot, that's a brilliant tip. Yep, that's definitely going to change the way I use Gimp.

Now the map posted above is a bit flat. Yes, it is clear and every element is distinct, but it's not particularly inspiring. To make the image pop we are going to add highlights and shadows. To do this we use an overlay layer.

First we will do general light and shade. Create a new layer and fill it with 50% grey (#808080). Your whole image will go grey! Don't worry, set the layer blend mode to overlay. Suddenly yourwhole image will go back to normal. Name this grey layer 'Sea light/shade' or somesuch.

Now The purpose of this layer is to give light and shade to the whole piece. This is done through overlay. Any colour value above 50% grey will have the effect of lightening every layer beneath it - up to and including your parchment background. The amount it lightens the layer is proportional to how much lighter than 50% grey the value on the overlay layer is. The opposite is true for values darker than 50% grey.

So to block in some light areas we need to lighten the overlay layer away from 50% grey. Now we could do this by laying down a lighter grey with the paint tools, but I find it easier to usethe dodge/burn tool on the grey layer. There's a good reason for this, but I won't go into it here unless people are interested.

Go to the dodge/burn tool and pick settings such as these:


Now, dodge lightens tones whereas burn darkens them (it's a little more complex than that when dealing with colours but the purpose of what we are doing here this will suffice for now). By using a large fuzzy dodge brush on your overlay layer you will see whole areas of your map lighten up. Switch to burn to drop in the shadows. So for example if we have an overlay layer that looks like this:



and we apply this overlay layer to the image I posted above, then we get something that looks like this:



Now obviously a lot of the overlay regions that are making the waves dark are also darkening the ship, which is exactly what we don't want. Do we go back and paint those bits of the overlay 50% grey again? No! We just add a layer mask to out overlay layer. Copy and paste the layer mask from the sea colours layer into this new layer maks and the image cleans up immediately:



See, I told you creating those layer masks would be useful in the long run!