Fig.04 shows the ice material.


The rock material is shown in Fig.05.

Composing two materials

The composition of the base materials (we will call the materials that receive a layer of snow "base materials”) with the snow material was made using the shader Blend and to mix the two materials the Falloff map was used as a mask, using a world Z technique.

To mix the materials the shader Top/Bottom could also be used (it substitutes the world Z technique). But to have a better displacement result I used the 3D Displacement option. This cannot be used inside the shader Arch&Design (used to make the base and snow materials), so the shaders had to be placed inside mental ray, using the Material to Shader option to make the connection.

As I had two different materials with two different displacement maps, which needed to have the same mix as the base and snow materials, I opted for the Falloff technique in world Z instead of the Top/Bottom option. This is because in the Falloff map itself there are two channels, one for each displacement map. This Falloff map is the same map that was used as a mask in the shader Blend.

Let`s see how that works (Fig.06).

Modeling

The terrain modeling was made inside 3ds Max using simple resources, such as the modifiers Noise and Displace.

After making a simple relief base, the mesh was subdivided to receive the Noise modifier.

After using the Noise modifier, which pulls and stretches the mesh, I performed the mapping of the object in order to make a new subdivision and used the Displace modifier to deform the mesh according to the texture that I was going to use.

And finally I created a new subdivision to leave the mesh uniform.

With all that, the mesh became really heavy, so now that I had the shape I desired, I used the modifier Multires to optimize the mesh. This option optimizes the mesh while still maintaining the mapping (in the case of the example in Fig.07, the mesh was reduced from 53000 vertex to 5300 vertex).




Now I was able to convert the mesh to an Editable Poly. For those who use 3ds Max 2010, the resource Quadrify can be used to correct the mesh and remove the triangular faces. For those who use older versions, the same can be achieved by using Polyboost.

Now the model was ready to be used (Fig.07).

For the modeling of the airplane I utilized the Box Modeling technique, using reference images found on the internet (Fig.08).

Mapping

The mapping was made in 3ds Max using Unwrap, with the Pelt Map tool, to open the mesh. However, using only Pelt Map doesn't give a very good result and so to correct the mesh I used the Relax tool, which can be found in the Tools menu. The option that presents the best result is the Relax by Face Angles.

With the mesh ready, all that was left to be done was to use the Pack UVV tool, also in the Tools menu. This tool correctly distributes the mesh inside the Safe Area of the Unwrap. If there is too much space left all you have to do is use the Scale tool and make the adjustments manually, but this entire process is usually pretty quick.

To have textures with a good detail level, I separated the airplane elements into groups to perform the mapping (Fig.09 & Fig.10).