ABSTRACT
Shaders allow for a stunning level of realism in games, and the rate at which the hardware is improving is staggering. I purposely wrote this book to address core principles of game art creation that don’t change or that change very slowly. Hardware and technology change rapidly, but that doesn’t alter the basics of texture, shader and material creation-at least not yet. Figure 3.1 shows some recent screenshots provided by Unigine Corporation of shaders in action. The top scene is from Tropics , a benchmark demo that depicts tropical paradise using many shaders: ocean waves stretch off into infi nity and undulate, sparkle, refract, and so on. The lagoon islands have sandy beaches with crisp shadows and crawling crabs. There is a ton of detail in this one shot alone as the sun sets on the scene, bathing the huts in color and shadow. The vegetation sways as a gentle ocean breeze passes through. In the animated version of this image (running in real time as a game), you can see the waves crashing on the shore and the clouds moving; there is a lot going on! The two following images show the DirectX 9 version and the DirectX 11 version of the same scene. You can see that the roof and stonework in the building are the places of the most distinction between the two scenes. In the image on the
left, the stonework is fl at; in the right, it stands out prominently, even casting shadows. This is because DirectX 11 now uses tessellation , which is one of the more important DirectX 11 features. Tessellation uses a height map to determine the extent to which a feature should protrude from a surface and actually divides up the mesh and pushes the geometry out from the surface.
