In our last outing we put together a simple map.* Having reached this point, the wise cartographer asks itself (when discussing cartographers I default to non-specific, non-human pronouns):* “Am I done?* Does this map suffice?”Actually, the answer to this question should have been determined before we even started.* One of my favorite professors used to say “Begin every project with a proposal.* It’s the easiest and best way to know when you’re done.”
Anyway, if the map you’ve already made suits your purposes, congratulations.* There is no reason for you to continue reading this, so by all means go back to whatever your favorite activity happens to be.* I promise I won’t take it personally.* If, however, you need a less simple map – or if you’re just like me (any map worth making is worth making pretty) – then please read on.
The plan here is to avail ourselves of some of QGIS’s advanced stylizing techniques to apply a variety of better looking symbology to the map.* We will work in an order the reverse of that which we used last time (top down as opposed to bottom up) because this neatly follows a least-to-most complicated trajectory (with one exception).
Structures
Our general goal here is to construct a believable illusion of three dimensions.* We aren’t going to try to achieve true 3D (or – more accurately – 2.5D), instead we’ll just use a few tricks to fool the eye.* In the case of the structures layer we’ll just apply a simple drop shadow.* Double-click on the ‘Structures’ layer to open the Properties window.* Click on ‘Style’ in the left-hand sidebar if it isn’t highlighted already.* Select a lighter color for the polygons (I used a grey: #707070), then check the ‘Draw effects’ box in the main area of the window.* Click on the small star that resultantly turned yellow to open up the Draw effects window.* Check the ‘Drop Shadow’ box on the left, change the Offset to 4 Map Units, change the Blur Radius to 1, and change the Blend Mode to Normal.* Click ‘Okay’ a couple of times and watch the map redraw itself.
Roads
Roads come in various shapes and sizes.* There are many different attributes of this layer we could use to symbolize our roads, but I think the wisest (read: easiest) way to go is to symbolize them by relative size.* If you right-click on the Title of the ‘Roads’ layer (in the Layers Panel), a menu appears.* Click on ‘Open Attribute’ and a window opens showing you the database that’s attached to the layer (most layers have them).* Feel free to have a look around, and don’t worry if much of it looks like gibberish.* The first column of the attribute table is called ‘Class’ and it is the one we will be using to symbolize the layer.* The road classes are single-digit codes ranging from 1 to 6 (scroll down the MassGIS ‘Roads’ page for an explanation of the classes).* The short explanation is the smaller numbers represent bigger roads and vice versa.* We want to symbolize thicker lines for larger roads, so we’ll just have to tweak it a bit.* Double-click on the ‘Roads’ layer to open the Properties window and change the line style from ‘Single Symbol’ to ‘Graduated’.* Click on the ‘
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