Shade basics
Shades, from the artist’s point of view, are often a bit of a black box. Our involvement usually requires that we generate input for a preexisting shade—set parameters and/or assign textures, and then look at the end result. Since the artist’s role is mostly confined to creating input and judging the output of the shade, we often have nothing to do with the code. In some cases, a shade code is written or edited by an artist, but most new shade-creation tools are more like the material systems in Max and Maya, requiring no programming knowledge.
Common shade effects
Like most things dealing with computer game technology, shades are a vast and complex topic riddled with new vocabulary, concepts, and technological requirements. In addition, each game engine and each game project will have its own vocabulary, process, and subtle nuances in dealing with shades. But you will always deal with some basic shade effects, and here are some samples of them. You may notice that these shade effects are very similar to filter effects in Photoshop, materials in Max or Maya, and many post video effects.
Masking and opacity
Masking typically uses a specific color that is designated the clear color and is more efficient than transparency. Transparency uses a separate channel or a grayscale image to determine the opacity of a pixel. The trade-off is that transparency looks better, but it requires more file space and more processing power. Masking can significantly speed up a huge scene with many overlapping elements with transparency on them, such as a forest or a jungle.
Average
Average blends the colors of the base map and the new map evenly. If you don’t want either texture overpowering the other in any way, use average. This is appropriate for creating an entirely new texture from two separate textures or, in conjunction with grayscale base maps, for coloring the base map.
Additive
The additive color model brightens the base map. Black becomes completely transparent.
Common shade effects
Like most things dealing with computer game technology, shades are a vast and complex topic riddled with new vocabulary, concepts, and technological requirements. In addition, each game engine and each game project will have its own vocabulary, process, and subtle nuances in dealing with shades. But you will always deal with some basic shade effects, and here are some samples of them. You may notice that these shade effects are very similar to filter effects in Photoshop, materials in Max or Maya, and many post video effects. Post video effects are effects inserted into a film or video after the footage is shot, during the editing process.
Bump, normal, and parallax occlusion mapping
These shades add 3D depth to an otherwise flat surface. While bump maps are grayscale and display the most limited 3D effect, the others add depth using a color map with lighting information encoded in it.
Conclusion
That was a quick look at what shades can do. We will implement all of them in the coming exercises to create various effects. Our implementation will be generic, meaning that we will create the assets for the shade based on the most basic parameters. If you are using Max, Maya, Unreal 3, or any other shade system, these basics will translate easily into those systems.
