Blender Render Materials
First, you’ll learn about how to set up materials and for that, you’ll want to explore the Material tab in the Properties Editor, shown in Figure 10.1. To make Blender display these options, you’ll need to create a new material or select an existing one from the list.
The following list describes what all those panels in Figure 10.1 are so you can have a better understanding of how to use them and their basic options:
Current selection: At the top of the Material tab, you can see the symbols and names of the object, and the material for which the settings are being displayed. As always, if you click the pin to the left, it will “pin” those options and will keep them visible even if you select a different object with a different material. This is handy if you want to compare two materials (remember you can have two or more Properties Editors in Blender) or if you’re working on a material but want to move things around without losing sight of it.
Materials list: In the Materials list, you’ll see the materials that are applied to the currently selected object. Yes, it is possible to apply more than one material to a single object (you’ll learn how to do it later). This list has different slots and when you select a slot, you can see the material that has been used in that slot and you can replace it with another material.
Current material: Under the Materials list, you’ll see the current material’s name. You can rename your materials in that box. If you see a number at the right side of the name, that’s the number of objects using that material: click that number to duplicate the material so you can modify it as a new material for only the currently selected object. You can also duplicate it by pressing the + button. If you want to discard the material for that object, just select a different material from the list or click the X button to discard it.
Near the material’s name you have the icon to enable or disable nodes. If you want to use nodes for this material in the Node Editor, activate that option to make it available.
Right under the material’s name you’ll see four buttons: these indicate the type of material with which you’re working. Surface is the usual material type. Wire shows only the wireframe (edges) of the mesh. Volume is used to simulate objects with volume such as clouds, smoke, and mist. Halo makes the vertices of the object shine and produces a halo effect.
Preview: The Preview panel shows a real-time preview of what the material would look like with the current settings. At the right side of the tab, you can select the shape in which you want to see the preview of the material.
Diffuse: The Diffuse panel is where you set the base color of the material. If you select the Ramp option, you’ll be able to define a gradient. In the drop-down list that appears, you can select the shader type you want to use (by default, Lambert), which will affect the algorithms Blender will use when computing the material’s surface.
Specular: In this panel, you can tell Blender if you want your material to be shiny and where you set the shine’s color, intensity, and hardness. You can also use a gradient for the shine by enabling the Ramp option.
Shading: You can set some options in this panel for how the surface of the material reacts to light. Emit will make the object look like it is emitting light. With the Shadeless option, the material will be unaffected by lights or shadows (you’ll only see the original color), which is very useful when you want something to appear in the render exactly as you colored it (such as with background images and videos that you use as textures in the scene).
Transparency: When transparency is enabled in this panel, your material will become transparent. Mask mode lets you display the background image where the material is shown. Z Transparency is a very basic transparency that renders fast and it’s simple to use. Raytrace is the most realistic option and it provides an IOR (Index of Refraction) option that makes the material refract light, which is very useful for simulating glass, for example.
Mirror: This panel defines the reflectivity of your material. You can increase the material’s amount of reflection and its color as well as some other options to make it look better (such as Fresnel, which smooths the effect toward the parts of the object that are not facing the camera). If you have a lot of reflective materials in your scene, you may want to increase the Depth value, which defines the number of times a reflection can be reflected in another reflection; it sounds crazy, but it’s very useful to prevent infinite reflections that would take a long time to render. Max Dist (Maximum Distance) controls over what distance the material can reflect until, after that point, it fades. Gloss options will make the reflections softer. The Samples option reduces the noise: the higher the samples number, the less noise reflections on the material will have, but more samples will also take longer to render.
Subsurface Scattering: This is a very interesting option you can use to achieve some complex realistic materials such as skin or rubber. Basically, it computes the light passing through an object, so the surface color will depend on the thickness of that part of the object. Imagine an ear, for example. If you put a light behind it, you’d see the light passing through the ear and becoming reddish because of the blood vessels just below the surface of the skin.
Strand: This panel has a set of options to define the material when you’re rendering particles.
Options: In the Options panel, you’ll find some advanced options for defining a material and you want to check the Blender official documentation for more information on what they can do. An interesting one is the Traceable option, which, if disabled, will prevent a material from casting shadows or producing reflections (i.e., anything that uses raytracing methods).
Shadow: This panel is very useful and you’ll be using it in Chapter 14. It allows you to tell Blender how you want the shadows to act with a material. If you have transparent materials, they’ll only cast transparent shadows over other materials that have the Receive Transparent option enabled, for example (to save render time). The Shadows Only option will make an object transparent, but when rendering, you’ll see any shadows cast over it, making this option very useful when you want to compose objects that cast their shadows on top of a photo or another image.
As you can see, there are a lot of options you can manipulate to get the desired result for a material. And this is only the tip of the iceberg because mixing all these properties with textures gives even more options and really nice-looking materials.
Caution
Remember that if a material is not being used by any object when you close Blender, it will be removed and won’t exist when you open the file again. If you really want to keep a material, make sure to press the F button next to its name (Fake User) to prevent Blender from deleting it.