This a very bare bones, (over-?) simplified primer to Terragen 2.
It skips a lot of stuff, generally when the defaults are fine. Hits all the main points though, and there's a few little tricks I picked up that some might have missed (even if you know 99.9% of the stuff here)
1. Terrain - To begin with, you'll need some terrain. We'll use Power Fractal here, since it's a good way to get it to go all the way to the horizon with a minimal amount of effort.
You can pretty much use the default values here - but feel free to play around with them.
2. Camera Movement - There is a good chance that your terrain fractal will leave you under the surface (if you see a lot of black, that's what happened). If you click the strange symbol in the top right, it expands to this. I've labelled the buttons, but they're pretty straightforward.
Red text means - don't use this. Tilt view does what it sounds like, and while it may have 'artistic' merit ... meh. Zoom in/out isn't so great - In isn't so bad, but Out causes some very strange stretching (which shows up on the final render).
It's much better to use the centre controls and go closer/further with those. It's a digital landscape, so you won't get tired from 'walking'.
3. Shaders - The base colour is the main part of your landscape, you can eventually cover it up with surface shaders (more on that later) but you should usually pick your main colours here anyway.
You'll notice that on the different buttons the main window only show a preview of everything to the LEFT (there are some exceptions). If you're on the "Shaders" tab, you won't see "Atmosphere" or "Water" - even if you've already put them in your scene.
4. Surface shaders - can be limited by Altitude, Slope and a lot of other things. We'll start with just Min Alt. There is a trick to finding the right altitude which I'll get into when doing "Water".
5. Water - Not every render needs water, but it's worth covering here. It's somewhat limited (at least through this tab) so I've cropped out the top part ("Lake" is the only thing listed)
The important thing here is determining the altitude. Note the highlighted areas - the mouse is at a certain point, the y value at the bottom is where that is, and I've set the "Water level" accordingly.
You can also trial and error, but it takes longer. You can also assign a water shader at step #4 if you don't want a flat surface (and are prepared to wait)
6a. Clouds - as you can see there are a few types. If they are going to be prominent/close in your image I'd reccomend 3d. But 2d aren't too bad either.
Like water, you have an altitude, but you also have a depth.
I'm skipping over the "Atmosphere" bit for now, but feel free to play with the variables. Any of the changes here are noticeable quite quickly (Redsky, Bluesky, Decay etc).
6b. Quality - Among the many (many) options for clouds is "Quality". It defaults to about 0.43 -- setting it up to 1 will make a rather noticeable difference in the final image (more or less 'grain' at the edges), but won't actually increase render time by much. Not that clouds are all that long to compute anyway (compared to rough water).
7a. Sunlight - the main thing here is Heading and Elevation. "Up" is the way the camera is facing. The yellow dot is the sun (duh?)
You can have multiple suns for that Tatooine render if you wish. Cheesy
7b. Changes - Sun moved to "Up" and a lower Elevation - quite noticeable even in the quick/rough end of the preview render.
8. Render - There are 2 choices here for rendering, but you can add more, or tweak the ones that are already up.
The demo is limited to 800x600 and a quality of 1. Careful as the default, even for "Full Render" is much lower than this.
One other thing to note here - The button highlighted at the lower right - "Copy this view to Current Render Camera" if you more the view at all - DO NOT FORGET to click this.
9. The final image (that you saw in little clips above)
A shader is a program or set of instructions used in 3D computer graphics to determine the final surface properties of an object or image. This can include arbitrarily complex descriptions of light absorption and diffusion, texture mapping, reflection and refraction, shadowing, surface displacement and post-processing effects. In Terragen 2 shaders are used to construct and modify almost every element of a scene.