hmm … but what about this that i have copied from the OpenGL programming guide?

"For real-world lights, the intensity of light decreases as distance from the light increases. Since a directional light is infinitely far away, it doesn’t make sense to attenuate its intensity over distance, so attenuation is disabled for a directional light. However, you might want to attenuate the light from a positional light. OpenGL attenuates a light source by multiplying the contribution of that source by an attenuation factor:

where

d = distance between the light’s position and the vertex

kc = GL_CONSTANT_ATTENUATION

kl = GL_LINEAR_ATTENUATION

kq = GL_QUADRATIC_ATTENUATION

By default, kc is 1.0 and both kl and kq are zero, but you can give these parameters different values:

glLightf(GL_LIGHT0, GL_CONSTANT_ATTENUATION, 2.0);

glLightf(GL_LIGHT0, GL_LINEAR_ATTENUATION, 1.0);

glLightf(GL_LIGHT0, GL_QUADRATIC_ATTENUATION, 0.5);

Note that the ambient, diffuse, and specular contributions are all attenuated. Only the emission and global ambient values aren’t attenuated. Also note that since attenuation requires an additional division (and possibly more math) for each calculated color, using attenuated lights may slow down application performance."

Shouldn’t i use this, or am i misunderstanding something?