This 3DS Max tutorial will help you create realistic, volumetric, clouds using a Particle Flow Source (PF Source), a procedural opacity map and a 3D object.

This tutorial is a bit on the long side but we believe the results are worth it. !Keep in mind that the result depends on a lot of things and it might not look exactly the same for you. This is why we’re providing you with the completed scene at the end of the tutorial.

1/5 The cloud geometry

Fire-up 3DS Max, go to the Render menu and click the Render Setup entry. Scroll down the Common tab and roll-out the Assign Renderer tab. Set mental ray as the Production Renderer.

We now need to create a base for our cloud. Keep in mind this has to be a sort-of random 3D object. You can start from a primitive and Extrude/ Bevel/ Scale until you get something that looks good. We’ve ended up with this:

If you don’t yet have the basic modeling skills needed for this, we recommend you read our Basic 3D Modeling tutorial.

If you just don’t feel like modeling something right now, you can import our cloud geometry. Download it here

! Finally, position your perspective view at interesting angle and press Ctrl+C to place a Camera there.

2/5 The Cloud Billboard

We’re going to create the 3D cloud’s surface using a PF Source. The technique is not that difficult (just tedious) but you should take some time to understand what we do here.

Switch to the Left view by pressing the {L} key. Go to the Create tab {} and select the Particle Systems entry from the drop-down. Place a PF Source anywhere in the scene.

With the PF Source still selected, go to the Modify tab {} and click the Particle View button. The PF Source already has a standard event defined. We need to modify this to suit our purpose.

We need to create a lot of particles that will “Stick” to the cloud geometry, make them face the camera we’ve created earlier (billboarding) and apply a material to them. !Right Click and Delete the Position Icon, the Speed icon, The Rotation Icon, and the Shape.

Select the Display object and set it to Geometry. This will allow us to preview our effect.

To stick the particles to the object, drag a Position Object beneath the Birth object. You can find it in the lower window list. Click the Add button and click the Cloud Geometry from your scene. Also make sure that the Location: is set to Volume.

To make the particles face our camera, drag and drop a Shape Facing icon under the Position Object one. Press the None button and click your Camera. Also adjust the Size and set it to 34 or so.

Finally, select the Birth icon and set the:

» Emit Start to 0

» Emit stop to 0 (particles are always on)

» Amount to 6500 or so (number of particles)

This may take a while to compute. Be patient.

At this point we can hide the original geometry to get a clear sense of what we’re doing. Select the cloud_base geometry, right click it and click on Hide Selection