Anyone can help me on fogs in gl ? thanks

OpenGL
1

i’ve been recently developing a software 3d rendering engine , just for fun , and for better understanding of the 3d rendering algorithms and opengl. i can project the geometry properly on the screen now , and use textures on the surface of the polygons , but now i want to use fogs in my texture shading, i just can’t figure out any efficient algorithms on it , andbody can give me anyhelp please~~ thanks, btw, i’m totaly a noob on gl stuff, lol~~~~

2

where can i see any exampel of your software renderer?

3

okay , here is the link to the code , but all these things are in java , since it makes things easier although there might be some defects in performance.
http://www.bronzeshow.com/Graphics.rar

all the texture mapping and geometry clipings are in Graphic3d.java ,and it used an integer array as a image buffer, and every pixels are in ARGB 32bit format. And all texture mapping was in a method called fillTriangle.
THX.

BTW, jdk1.5 might be required

4

Fog isn’t directly related to texturing. It simply takes the fragment’s post texturing color, and blends it with the fog color based on the fragment’s depth value.

  depth: fragment's depth value
  fog(): fog equation (see gl spec)
  Cf:    fog color
  Cr:    fragment color after shading and texturing
  C:     fragment color after fogging

  f = clamp(fog(depth));
  C = f*Cr + (1-f)*Cf

The exact specification is in Chapter 3.10 Fog, on page 191 of the OpenGL 2.0 Specification .