ShaderX Shader Programming Tips & Tricks With DirectX 9

Introduction
This book is a collection of articles that discuss ways to use vertex and pixel
shaders to implement a variety of effects. The following provides a brief overview
of these articles:
Section I — Geometry Manipulation Tricks
This section starts with a DirectX 9 sequel to Dean Calver’s vertex compression
article in Direct3D ShaderX: Pixel and Vertex Shader Tips and Tricks. Dean shows
a number of ways to reduce vertex throughput by compressing vertex data.
Carsten Wenzel points out how to use lookup tables in vertex shaders to reduce
the workload of the vertex shader hardware. A feature-complete and very hardware-friendly
terrain engine is explained in Daniel Wagner’s article, “Terrain
Geomorphing in the Vertex Shader.” The speed of the example program provided
with source is impressive. Creating 3D planets for a space-shooter type of game
can be done entirely on the GPU, which Jesse Laeuchli shows how to do in his
article “3D Planets on the GPU.”
The vs_3_0 vertex shader model has a feature called vertex texturing, which
Kristof Beets uses to create a very realistic-looking cloth animation in his article
“Cloth Animation with Pixel and Vertex Shader 3.0.” In “Collision Shaders,”
Takashi Imagire, who is known for the example programs on his web site
(www.t-pot.com), uses shaders to calculate collisions, something that has never
been shown before. The final article in this section covers using displacement
mapping as a method of geometry compression. The main aim of Tom Forsyth’s
article is to allow people to take data from the industry’s current mesh and texture
authoring pipelines, and to derive displacement map data from them.
Section II — Rendering Techniques
The section starts with an article by Greg James that presents a convenient and
flexible technique for rendering ordinary polygon objects of any shape as thick
volumes of light scattering or light absorbing material with ps_1_3. O’dell Hicks
shows in his article, “Screen-aligned Particles with Minimal VertexBuffer
Locking,” how to create screen-aligned particles with a vertex shader, bringing us
one step closer to the goal of having almost everything done by the GPU. “Hemisphere
Lighting with Radiosity Maps,” written by Shawn Hargreaves, shows a
lighting model that was designed for fast moving objects in outdoor environments.
Its goals are to tie in the moving objects with their surroundings, to convey a sensation
of speed, and to be capable of rendering large numbers of meshes at a good
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