Previous Chapter: Getting Set Up
Now you’ve got Blender and your heightmap, and so we’re ready to get started. First we’re just going to familiarize ourselves with some of the basics of how to get around the software. As I mentioned, this is a big, powerful, 3D modeling program, and we’re only going to use a tiny portion of its features. I’m going to skip over a lot of the different buttons that aren’t relevant to doing shaded relief — I’m no expert, so I don’t even know what many of them do. Probably some interesting stuff in there, though, so if you figure out an interesting cartographic use for some of the software’s other features, I’d love to hear it. Meanwhile, though, we’re going to keep it simple and focus only the few parts of the software that we need.
When you start up Blender, it should look roughly like this. You’ll see a version number, along with a cool example of a project that someone did using Blender.
Click outside the central image box to make it go away. Now you’re left with the default Blender scene: a cube, a camera, and a light source (called a lamp).
You can think of it as sort of a virtual photography studio. We’ve got something we want to take a picture of (a cube, in this case), a lamp to provide lighting, and a camera to capture the image. We’re going to make some changes to this setup, but this is the basic idea behind doing Blender relief: we’re going to make a model of our terrain, light it, and photograph it from above. It’s a digital version of the relief techniques of Karl Wenschow, who worked in the early 20th century. Instead of doing shaded relief by hand, as was common then, he built large plaster terrain models and photographed them in a studio to generate his relief images.
We’re going to start by learning how to navigate our 3D scene in Blender. But before we begin zooming and panning around, there’s a little wrinkle: Blender assumes that you own a 3-button mouse, and it uses the middle mouse button for some of these navigation functions. I don’t have one, and I’m guessing you don’t, either (maybe they’re more popular in the 3D modeling crowd?). So, let’s first adjust our settings to tell Blender that we’re just simple people who own simple, 2-button devices.
Head on over to the File menu in the upper left of the program, and choose User Preferences.
Choose the Input tab (if it’s not chosen already), and check Emulate 3 Button Mouse Notice that if you hover over the checkbox, the tooltip says, “Emulate Middle Mouse with Alt + Left Mouse.” So, now holding the Alt key and clicking the left mouse button will act in place of pressing the middle mouse button that we don’t have. You’ll be making a lot of use of that. Once you’ve got that selection made, you can click Save User Settings and close the User Preferences window.
So, let’s first practice rotating around the scene. If you hold Alt and click and drag (or middle click and drag, if you are blessed with a 3-button mouse), you’ll rotate around your scene. To pan around the scene, you’ll hold Alt+Shift and then click and drag. To zoom in and out, you’ll hold Alt+Ctrl and then click and drag up and down. You can also zoom in and out with the scroll wheel. This stuff can take some getting used to, so mess around a bit until you get the hang of it.
As said, this is a virtual photographic studio, and if you pan and rotate around you should be able to see that the camera is positioned such that it is set to capture a picture of the corner of the cube. Let’s see what that picture looks like. Go up to the top menu and choose Render, then Render Image. Rendering is the term we use for taking virtual photographs in our virtual studio. You should see something like this:
This rendered image should make sense to you, based on where you see the lamp, cube, and camera positioned. Later on we’ll make some changes to all of these things. Hit Escape: this will take you back to where you were before we did the render, which is called the 3D View.
Let’s move on to other areas of the interface. From time to time you’re going to need to select objects in the 3D view (such as that cube, for example). There are two ways to do that: you can either right-click on the object in the 3D view, or you can left-click on the object’s name in the Outliner, which is the little layers panel on the right side of the screen. Things you select get highlighted in orange by default.
I personally find that right clicking is confusingly nonstandard, and so I usually stick to left clicking on the Outliner. If you mistakenly left-click in the 3D view, nothing bad will happen. You’ll just move around a little red-and-white object called the 3D cursor, and we’re going to ignore it because, for the purposes of this tutorial, we don’t care what it does.
Adjust Some Settings
Now we know our way around the interface, or at least the tiny portion of it that we need to understand. Before we get in too deep, make sure to go up to the top menu and choose File → Save, so that you can keep your progress in the event something goes amiss. You probably will want to keep doing this at regular intervals.
Next up we need to tweak some settings. First off, notice on the menu bar there’s a dropdown that probably says Blender Render. This is the particular rendering engine that Blender uses to calculate the way our scene should look, based on things like the position of the light source, the materials our 3D cube is made from, etc. I know very little about rendering engines, but it turns out there are multiple of them, and we want to use a different one. From the dropdown, choose Cycles Render.
Cycles is newer and, in my limited experience, seems a little easier to use. It also uses different methods to calculate how scenes look. If you go back to Render → Render Image again, you’ll notice that the resulting image looks different from the render we did when the setting was at Blender Render. Hit Escape to head back to the 3D view.
In any case, Cycles has some useful abilities that the Blender Renderer doesn’t. You need to switch to Cycles now, or several of the items I talk about later on in this tutorial either won’t make sense or won’t even show up in the program at all.
Now that we’ve switched to Cycles, there’s one more initial setting to tweak. On the right side of the screen, there’s the Properties panel. It’s got a bunch of little icons on top, each one leading to a new page of options. One of them looks like an old still camera, which takes us to our scene’s Render Properties. Click on it if it’s not already selected — it probably is, though, unless you clicked some of the other icons while exploring the software.
Near the top of the Render Properties, you should see a dropdown marked “Feature Set.” Change the setting from Supported to Experimental. I imagine in some future version of the software these settings won’t be experimental, and I’ll try to remember to update the tutorial when this happens. Meanwhile, this setting enables us to actually follow the rest of the tutorial, since the method I use relies on some cool new Blender features.
We’re working with vectors in Blender, just like we work with vectors in other programs like InkScape or Adobe Illustrator. To see what I mean, let’s select the cube, by either right clicking directly on it, or left clicking on its name in the Outliner. Then hit Tab to go into Edit Mode. Notice that Blender is showing us that this cube is made of eight vertices connected together. These 3D vector objects are called meshes in Blender.
In Edit Mode, we could make some adjustments to these vertices and deform our cube, though we don’t really need to right now. Feel free to right-click vertices and move them if you want to play around; it’s fine it the cube ends up deformed. Hit Tab again to go back to Object Mode, or select it from the dropdown menu on the bottom bar. We’ll need to switch again between Edit and Object Modes later on, so remember that one.
We can add meshes in Blender by hitting Shift-A, which brings up a menu of options, including the choice of several meshes. Try adding a few for fun. Notice they show up wherever the 3D cursor is (that weird object that you move around by left-clicking), so feel free to move that around to make them appear in different places. We’ll learn more precise ways of positioning meshes later. Try checking out individual objects in Edit Mode to see what they’re made from. To delete any object, just hit Delete when it’s selected.
We’re not trying to do anything specific here — the goal is just for you to see and understand what meshes are, so have fun. Once you’re done, we’re ready to move on and get started building our actual relief.
Next Chapter: The Plane