Tutorial: Clouds for Professionals -- Version 2

Ever wondered how some of the Terraholics produce those cool looking, thick clouds?

I’ve gathered some of the tricks and compiled them here. When I started off with Terragen, I found it quite a bit difficult to get there. So, if you’re a newbie, I’ll save you a significant amount of time if you read through. In case you’re a professional, you might catch one or another hint of some things you always wanted to know. Here we go:

  1. Explaning the settings

I’m not gonna go through all this again, since many others have done this before. Look at to get the basics. Anyway, I’m gonna tell you something about clouds in general and which parameters have what type of effect in my own words.

The Darkening Slider

This slider simply controls the overall brightness of the clouds. If the entire feeling of the sky should be thick and dark – bad weather style – push the slider to the right.

The Cloud Color

Use this one to strengthen the effect of how sunlight colors the clouds at sunsets or to better create clouds of thunderstorms. For example, thunder clouds very often look brownish/yellowish shortly before it all comes down. Play with this setting each time you want to have the clouds support the overall “feeling” of the scene. The standard settings are mostly perfect for high noon good weather scenes.

The Density Contrast Slider

Well, if you keep this setting low, the clouds will get brighter in terms of having more light pass through them the closer the rays get to the clouds edges and get darker towards the center of the cloud. If you want clouds to get more dark, slide it to the right. Having less contrast greatly helps with making clouds more 3-dimensional (since you will see more details towards the center of the cloud!). For many scenes, it’s good to leave the slider between 20-30, with persistence at about 40-50. But if you want the clouds to be ‘sharp’, a higher contrast  will be better. This is also helpful, if you need well defined and very visible sunbeams.

The Density Shift Slider

This one is easy. This setting simply tells the cloud generation algorithm to cover more space by the clouds. So, more shift, less blue sky and vice versa.

Clouds Persistence

Want to have clouds dissolve more smoothly? Want to get rid of strange “sprinkles” in the sky? Solution: Lower the persistence, which makes the boundaries of the clouds more defined. Otherwise, would you want to have clouds which kind of “spawn” baby clouds beside them, slide that piece to the right. Usually, in many real scenes clouds get transformed by the wind, which sometimes devides small pieces of the larger clouds. But don’t take this to far, it will screw up your sky scenery a lot! The clouds might appear pixeled all over.

Clouds Cast Shadows

The name says it all. That’s what they do, usually. For realistic scenes, you need to have this option checked. But in case your sky looks great but the landscape looks like a deep black hole just because the clouds cast large shadows, maybe you should consider to uncheck it. But more effectively, try to increase the shadow lightness and perhaps increase the exposure factor more.

Where Cloud Casting Not Used, Use Uniform Shadow

This has no effect unless you leave “Clouds Cast Shadows” unchecked. In case it’s uncecked, the slider kind of defines how much the terrain brighness decreases when you push it to the left– but this is for the entire terrain, then.