Cinema 4D Handbook: Chapter 5, Part I

All through September I am going through the Cinema 4D, r10 Handbook in hopes of gaining a new skill and better understanding of 3D modeling. I plan to (from here on out) cover two chapters a week (longer chapters will be broken into multiple posts). Stay tuned for new chapters.

Chapter 5: Materials and Textures

“Materials are the visual clues that reference the tactile and visual qualities of a surface.” The term material is interchangeable with texture. Everything in the real world has texture, and the 3D world should be no different. Materials are managed in the Materials Manager.

When you create a new material a sample swatch appears in the Materials Manager. “Each of the instructions that define the material is called a channel.” Selecting the material will open the Materials Editor. To edit a channel, all you have to do is select it, then adjust its properties within the Materials Editor. Some of the channels allow you to import reference images. Also known as Texture Maps. You can edit the properties of each individual channel, but all selected channels take into all the other selected channels to create the final texture.

Procedural Shaders

There are two types of shaders, volume shaders and  material channel shaders. “Procedural shaders are mathematically derived and thus are independent of pixel-based images.” Volume shaders have their own properties and deliver a specific look and feel to your texture. Material channel shaders are shaders that are edited within specific channels of your texture. To choose a material channel shader, you go into the channel then use the texture drop-down menu.

***Chapter 5 has three tutorials. But the first two are less about learning how to perform a specific skill, and more about learning what specific effects do. So, instead of doing a summarized walk-through of the tutorials, I’m going to sum up what the specific effects do, and how to use them.***

Tutorial 5.1: Applying Materials

To create a new material, go into the Materials Manager. Then File> New Material. To activate a channel, click the check mark for it in the Materials Editor (to enter the Materials Editor, double-click on the material swatch). The book stresses naming your materials. Makes sense to me. By naming objects, materials, tags, etc, you are able to stay organized and to better communicate with co-animators.

To Link a Material to an Object:
1) Click and drag the material swatch to the Objects Manager and drop it on to the target object.

Effect: Subsurface Scattering
This effect lives inside the Luminance Channel. Subsurface Scattering mimics light passing through objects. Changing the strength will determine how little, or how much, light will pass through an object. *NOTE: This effect works in conjunction with lights. No light, no effect.

Tutorial 5.2: Layered Shaders

Before getting to far into this, the book discusses File Structure importance. When structuring your files (where everything is saved), it is important to remember that in order for C4D to recognize and render any materials, you must place a “tex” folder in the same root as the project file. All of your textures are then saved in that folder.

Shader: Layer Shader
Apply the Layer Shader in the Color Channel. The Layer Shader works similarly to Adobe Photoshop’s layer. You can add layers and change how they all affect each other.

Shader: Fusion Shader
The Fusion Shader takes two images, colors, or shaders, and combines them to form one shader. “The difference is that the Layer Shader can have many different layers, but Fusion is limited to two layers with a few more options.” In the case of this tutorial, the Fusion Shader is being used within the Layer Shader to create a nested effect.

Effect: Lumas
Within the Fusion Shader is an effect called Lumas. This effect helps to create metal-like surfaces.

Effect: Specularity
Inside the Lumas Effect is an option for Specularity. “Specularity is similar to a reflection but only reacts to the lights in your scene.” It creates bright spots on objects they are applied to.

Effect: Anisotrophy
Anisotrophy changes how bright spots appear on a material. It makes them more metallic looking.

Shader: Noise
For this example, the Noise Shader is being used as the second layer within the Fusion Shader. Here, it varies the color value over the surface of the material.

Shader: Fresnel
The Fresnel Shader, used as an overlay on the Layer Shader, changes the color of the texture “depending on the angle of the surface to the camera.” Basically, if the model turns, the effect of the Fresnel Shader will alter. Because it was changed to an overlay in the Layer Shader, the Fresnel Shader is interacting with the Fusion Shader.

Inside of the Reflection Channel, Fresnel will change the amount that an object will reflect.

Effect: Ambient Occlusion
Inside the Diffusion Channel lives an effect called Ambient Occlusion. This effect shades an object’s area of intersections or corners. (EX: where a wall meets a floor.)

Channel: Environment
Environment is a reflective channel that reflects image maps onto objects in a scene. Inside of the channel, you can select an image map inside of the texture option.

Channel: Bump
The Bump Channel simulates roughness on a surface without altering the geometry. Use the Noise Shader to spread and randomize the bumps.

Channel: Displacement
Like the Bump Channel, the Displacement Channel simulates roughness on an object. But, it will alter actual geometry. Use the Noise Shader to spread and randomize the displacement dents.

Channel: Alpha
“This channel uses grayscale values, which tell the material where to be solid and where to be transparent.”

The Texture Tool
The Texture Tool allows you to move, scale, and rotate a texture to manually place it in the editor.

Tutorial 5.3 is a pretty good introduction into using BodyPaint to unwrap and texture models. So, I’m breaking it out into its own post.

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