Shadow Mapping

OpenGL OpenGL: Basic Coding
1

Hi,

I’ve successfully implemented shadow mapping into my OpenGL demo.

However, is there a way of performing shadow mapping with using OpenGL extensions?

The manner in which I’ve done this has been to use the GLEE_ARB_depth_texture and GLEE_ARB_shadow extensions. (Obviously with the GLee implementation…)

How were shadows (depth map comparisons) peformed in ye olde days?

Thanks for your help in advance!

2

You mean “performing shadow mapping without using OpenGL extensions” ?

3

Yeah.

4

it was, and still done efficiently, blending textures and texture coordinates transformations:
http://www.paulsprojects.net/opengl/shadowmap/shadowmap.html
http://http.developer.nvidia.com/GPUGems/gpugems_ch14.html
http://developer.nvidia.com/object/prog_tech_docs_by_date.html

5

I’ve based my own shadow mapping demo on the paulsprojects link you’ve posted above - but even this demo uses OpenGL extensions to copy from the depth buffer and perform depth buffer to depth texture comparisons…

I’m looking at writing shadow maps in a way that doesn’t use any OpenGL extensions like this.

Anyone?