Introduction

In Unity you’ll want to change the transforms of your objectinstances quite often. The transform of an object determines its position, rotation and scale (size) in the world. If you want to do anything beyond changing textures on a static scene, there is no way around manipulating the transform. Now, this is hardly a problem when translating (changing the position), or scaling (changing an object’s size).

This article is about stencil testing: a functionality you can use when writing shaders. It will discuss what the stencil buffer is, and gloss over some possible applications of the technique. It also contains some ideas that you might be able to execute using stencil testing.