In ZBrush, the appearance of any surface is affected by several things – its base color, its texture image (if it has one), the lighting that falls on the surface, and its material. The material changes the way the lighting reacts with the surface so that it may appear – for example – shiny, bumpy, reflective, metallic or transparent. There are many preset materials in ZBrush to give you control over a scene. In addition, each material can be modified to create new materials. You can make your own custom materials or get them from ZBrushCentral, the Pixologic MatCap Library and elsewhere.
You can make sure a custom material is available each time ZBrush starts by saving it to the ZStartup/Materials folder. Don’t overload this folder though, as this could impact on ZBrush’s performance – keep below a maximum of 25 materials.
ZBrush starts with a set number of materials. The exact number depends on how many custom materials there are in the ZStartup/Materials folder but once ZBrush has started, the number of materials available in the Material palette does not change.
Materials can be thought of as occupying slots. When you load a new material through the Material > Load button it will replace the currently selected material in its slot. So, for example, if you select the Red Wax material and load a new material called Blue Mist, the Red Wax material will no longer be available. Furthermore, wherever you have used the Red Wax material on the canvas, or a model, it will now be replaced by Blue Mist.
This can take a bit of getting used to but it is a very powerful way of working with materials. It means that you don’t need to regard any material in ZBrush as ‘fixed’ – it can always be changed.
The one material that can’t be replaced is the Flat Color material. If you load a new material with Flat Color selected then the displayed name will be changed but the attributes will not.
Materials for 2D illustration
To work with materials in ZBrush, first make sure that the MRGB button (for color and material) or the M button (for material only) in the Draw Palette are pressed. Note that for many operations, the MRGB button is on by default.
Now select a material, choose a tool from the Tool palette that creates pixols, such as the SimpleBrush or a 3D tool such as Sphere3D, and start drawing. Whatever you draw will use the selected, or Active, material.
If you choose a different material, under normal circumstances nothing will change in the document, except anything you draw from then on will use the new material.
Materials for 3D models
If you are working with a 3D object such as the Sphere3D or a polymesh, the new material will only be applied if the object is in Edit mode or the Move, Scale or Rotate Gyro is active. The default behaviour for a 3D model in Edit mode is for it to take on the selected material.
To paint particular materials on a 3D object, the materials must be embedded. Embedding the material stops the default behaviour and the model will display the embedded material whichever material is selected in the Material palette. To embed a material you need to:
- Make sure the M or MRGB button is on in the Draw palette
- Select a suitable base material to work with
- Press Color > Fill Object
After doing this, you will be able to paint on the model using other materials. Simply select the material you want to use, make sure that the M or MRGB button is on, and paint.
Types of Materials
The Material palette shows many different materials. However, there are only five basic types of materials; the others are variations of these basic types.
Flat Color Material The Flat Color material is not a true material in that it has no shading or other material attributes. It is pure white and appears incandescent alongside other materials.
FastShader Material The FastShader Material contains only diffuse and ambient attributes. It is primarily used for modeling when simple shading of the model is required.
BasicMaterial The BasicMaterial forms the basis for most of the standard materials, including:
- Toy Plastic
- Double Shader material
- TriShader materials
- QuadShader materials
These materials contain all the same attributes as a Basic material except that they have either 1, 2, 3 or 4 shader channels.
Fiber Material The fiber material adds 3D hair-like strands to the image. By default the hairs are drawn along the surface normals (so on a sphere the fibers will appear sticking straight out), though you can adjust this and other fiber properties in the material settings.
MatCap Materials MatCap materials use image maps to simulate the effects of lighting on different types of surface. As the lighting is fixed by the image map, they do not respond to changes made in the Light palette. MatCap stands for material capture and using the MatCap tool you can quickly create your own MatCap materials that effectively simulate real world surfaces.
To learn more about MatCap see the MatCap page.