Hi there,
I’m currently trying to learn how perspective projection works in 3D graphics rendering. I need to understand this, because I’m trying to calculate view-space position of vertices using information from depth buffer. Plus it’s really useful and basic knowledge:)
Anyway, the most popular search result is this:
http://www.adobe.com/devnet/flashplayer/articles/perspective-projection.html
I find this article really confusing and it also references to an old class - PerspectiveMatrix3D.
Here is some information how Stage3D projection actually works:
http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/geom/PerspectiveProjection.html
http://help.adobe.com/en_US/as3/dev/WS36223081-8938-4b45-BB89-F1F8B1A52E4E.html
To obtain detailed knowledge about 3D to 2D projection, read this:
http://www.scratchapixel.com/lessons/3d-advanced-lessons/perspective-and-orthographic-projection-matrix/perspective-projection-matrix/
I think this article is really well-written and provides a lot of explanation of basic concepts.
Finally for math lovers, an indepth look at openGL projection matrix:
http://www.songho.ca/opengl/gl_projectionmatrix.html