• org : origin of the light - where the light will be.
• intensity : not the exact intensity of the light, but the radius of the light - the light is a sphere-like object and points within that object are lighted up, and the closer something is to the origin of the light (org) the closer the light will be to the actual colour data of the light.
• r : amount of red light.
• g : amount of green light.
• b : amount of blue light.

r/g/b is the colour data of the light (normalized, so the highest value, 255, is 1.0)
This function will add a light to the game at org, which has a radius of intensity units, and the colour data which is shown in the variables r, g, and b. The highest number for an RGB index is 255, but in Quake 3 the colour's index is divided by 255 to give a normalized value.

Say I want to make a purple light. The colour data for purple in RGB is 255,0,255. So the normalized values for this colour are:

255/255 = 1.0
0/255 = 0.0
255/255 = 1.0

So to add a purple light at the vector x, and radius 2.4 I would write:

trap_R_AddLightToScene( x, 2.4, 1.0, 0.0, 1.0 );

This function has no return value.

Nith Sahor