Simple Clouds

This tutorial will guide you through the creation of your own skies and clouds in Bryce. First we will do a quick overview of the Sky Palette, then an approach to making your own clouds in Bryce will be discussed. I would personally like to thank Martin Murphy (the artist who made the picture on the Bryce4 box) for his willingness and helpfulness in sharing his technique. This is a variation of the technique he uses to create the billowing clouds in his scenes.

The Sky Palette – a quick review

Cloud Frequency and Amplitude

1. Select the type of cloud by selecting either stratus or cumulus (or both).

2. Adjust the cloud texture by double clicking which will open the material editor.

3. Set the cloud coverage and colour by simply dragging left or right.

4. Set cloud altitude by dragging left or right.

5. Set the frequency and amplitude of clouds. It may be necessary to change the Sky Mode to get the appearance you want.

Enough of the basic stuff. Let’s make a cloud!

Create the first cloud sphere and set the material

To create your own cloud, a cloud material is applied to a group of spheres. So start with a sphere and apply a preset cloud texture to it. Here I used Cotton Ball II.

If you render the sphere now, it will have that nice fluffy feel to it that you want a cloud to have. However, to make a large cloud you must make the spheres larger or you will have too many spheres. It will take forever to render the clouds and it will lose the fluffy feel. The image to left shows 48 Bryce Units ~2x normal size.

Notice that when you resize it, the texture will become unreal because the frequency isn’t right. It’s important that the appearance of the first sphere looks good at about 20x the normal size. So you have to change the frequency of the cloud material. The image to the left shows 400 Bryce Units ~20x normal size

So a very rough rule of thumb for you to consider when making a cloud sphere is for every 2x size increase in size of the sphere from its default (20.48 Bryce units) decrease the frequency 2x. (you can do this until the frequency reaches 0, then this rough rule of thumb won’t work) For instance, the sphere above was 40 Bryce units in size in the first picture, I did not change the material frequency. However, when I resized the sphere to 400 Bryce units, it lacked "wispiness", but when I changed the frequency, the effect returned.

Sphere 48 Bryce Units, Frequency Default of 62.5 (here the frequency could have been changed, but I didn’t feel it necessary)

Nice and wispy

Sphere 400 Bryce Units, Frequency Default of  62.5  (just for a demonstration of a bad frequency)

Notice the really spherical appearance of the cloud sphere.

Sphere 400 Bryce Units (roughly the sphere was doubled in size 5x), Frequency changed to 5.5 (reduced the frequency roughly 4x [60/2 = 30: 30/2 = 15: 15/2 ~ 7: 7/2 ~ 4] to show the correction of the bad frequency) I played a little with the frequency and decided I like 5.5 better than 4.0 for the frequency.

Remember this is a very rough rule of thumb to use when increasing the size. You may find that you like a different effect. If so, then by all means use it!

Reminder: Drag the frequency control in the material editor to change the frequency of a material.

Make the Cloud

I elongated the sphere in one plane making an egg shape to give some character to the cloud sphere. However, when you make your clouds, you may want to leave them round. That decision is totally up to you.

Now duplicate the sphere and reposition it by dragging. Keep doing this until you have a cloudish shape.

This is the beginning of my cloud. I added more spheres before I stopped.

Go to a different view of your cloud and position some spheres in a different plane. This will give it a better 3D appearance.

Top view of the cloud.

Then do a 3D disperse/size on the cloud sphere group. This will make it appear more random. Remember that short bursts of this effect will provide superior results to one long drag.

Remember, dragging the green ball with the mouse will do the 3D disperse/size.

Do a quick render of your cloud to see if there are spheres that you need to change the frequency on, reposition, or delete.

Once your happy with the first cloud then you can go on to moving it to the right place in your scene.

Reposition and resize the cloud

If you turn the cloud so that it is at an angle to the camera it adds to the effect. So group the spheres and rotate the entire cloud slightly. Next drag the cloud till it is behind any terrains in your scene. To see the clouds, it may be necessary to increase the size of the cloud group. If the frequency doesn’t appear right, you will want to decrease it.

If you want more clouds, just duplicate this one. Rotate, reposition, and resize it to suit your taste. If the frequency ever gets off, you will want to decrease it.

This should have shown you one way to make your own clouds. You will want to practice doing this. I have to confess that the first time I made a cloud, it looked like a bunch of fuzzy balls in the sky; so keep trying. After all, just because it doesn’t come out right the first time, doesn’t mean that you can’t fix it.

Your final cloud appearance will also depend on what sky you have used. I chose a stormy sky which darkened the clouds, but you may want a bright blue sky, which will produce bright white clouds (or shine the sun on the clouds, here they were in shadow).

Remember to get the texture right on the first sphere after you resize it to roughly 20x the original size. You may want to make the cloud sphere larger, maybe 25x, or even 30x to start. Hopefully, by the time you reposition it behind any mountains in your scene, you won’t have to change the size much to make the clouds visible. If you do, just change the frequency again to suit you. I like to reduce the frequency, but you may want to increase it. Again this is totally up to your eye.

Also this is not meant to be an all inclusive instruction on every possible way to have made the final image or produce the desired results. Bryce offers zillions of wonderful ways to replicate, multi-replicate, reposition, etc. in its powerful interface. Experiment!