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[edit] Introduction to Shading

The purpose of this section is to guide you in understanding the full array of Blender's shading options and how to use them. Shading is the process of applying color, textures, and finishes to your meshes in order to simulate a wide variety of appearances, including patterns, actual painting and detailing, faces of people and animals in a variety of settings.

While Blender does offer painting abilities, those abilities are geared toward animation or coloring meshes. At a fine level of detail, such as skin UV textures or matte paintings, it does not compete and does not hope to compete with ease of use and functionality in specialized paint programs such as Gimp or Photoshop. Instead, it seamlessly uses their output graphic files for mesh and scene colorization.

[edit] Basics: Materials and Textures

In the next sections, we will discuss Procedural Materials and Textures. These types of materials and textures are applied as a procedure across the entire mesh. In Multiple Materials we will discuss how to apply a material to a set of faces. Since a mesh can have many sets of faces, a mesh can have many procedural materials, each with its own color and other material settings, as well as procedural textures.

In Textures, we will see how textures such as clouds or wood grain can have subtle or dramatic effects on the appearance of a mesh, and how they overlay or enhance the base material in some way (depending on how they Map Output) and mix with previous textures.

[edit] Advanced: Vertex painting and UV texturing

After the basics, we will take our shading to the next levels: vertex painting and then UV texturing using images. Please note that these levels of complexity and detail work together. Images can be combined with vertex colors to make the texture brighter or darker or to give it a color. Using an special texture, the Image Texture, as a UV Texture is a way of giving very detailed, precise coloring to a mesh in order to achieve photo-realistic imagery.

Consider our favorite model, Suzanne the Monkey. Below you will see, in order of increasing realism (and complexity), the results that can be achieved with each style of painting.

In the picture to the right, a single material, brown, was used to color Suzanne. A cloud texture was applied to the Color to blend in a darker brown, as well as making it look bumpy (Normal) and to vary the specularity. Use this paint technique for an object that is physically made from a single material, like chocolate, plastic, or metal. Use one of the grain textures for wood or marble. Or a milk chocolate monkey; just eat the ears first.
In the picture to the right, a few materials, brown for fur, pink for nose and lips, etc. was used to color Suzanne. A cloud texture was applied to color her skin, and a veronni texture to her pink nose and eyes. A Vertex Group, Scalp, was defined to generate static particles (hair).
In the picture to the right, Vertex Painting was used to color Suzanne's mesh. A green scalp was used to generate a mohawk using static particles. Her right eye has the center vertex duplicated, set to single user, and a halo material was used to put "a twinkle in her eye". Her left eye has the cornea rotated to so that the vertex colors twist. Both eyes were filled in on the back side and vertex painted with green colors and also have Z-Trans enabled to allow the back to show through. Lights are placed in front of her eyes to highlight them.

Since Vertex painting shades between faces, notice how the skin colors blend more smoothly than the previous example. Her skin has a more natural appearance with colors blended (and not being blocky or single-colored).

In the picture to the right, a single image was used as a UV Texture to color Suzanne. A xxx texture was applied to xxx.

Contents 1 Introduction to Shading 1.1 Basics: Materials and Textures 1.2 Advanced: Vertex painting and UV texturing