I'm taking my first venture in to writing a shader and what I really need to do is create a billboarding effect. A thorough Google search turns up a number of threads on the topic and they always end with
A) Figured it out. Thread closed.
C) "long language/system-specific answer without explanation"
Most commonly, people are directed to Riemers which is fine, except his code isn't compatible with XNA 4.0 (what I'm using) and he doesn't explain the shader itself.
Can anyone explain/direct-me-to a language/system agnostic answer of how quad billboarding works?
EDIT: For others so they don't need to dig through the comments: NtscCobalt pointed out that I was attempting to use an orthographic camera when applying the shader. This essentially voided some of the effects of the shader. After changing to a perspective-based cam, the shader worked as it should have.