   BSP Entity Lighting
  My BSP rendering engine works more or less the way I want it to, lightmaps etc work and it looks good.Just wondering how lighting other objects is achieved though?I'm guessing that I need to discover the distance from the lights to the object and light it accordingly?What's the best way of doing this? Ideally an entity would have to discover how it is lit by any light in the map but I figure this is impractical since the performance hit would be pretty bad.Any advice?   
  FYI, the Quake engines handled this by dividing the world volume up into cells and associating a light value with each cell. I'm not sure exactly how big the cells are, but they're probably on the order of character-sized or smaller. I believe the lighting values for each cell are calculated as an average of the lightmap texel values in that cell. At runtime, the light value for the cell is applied to the vertices of any object in the cell.I haven't actually looked at that part of the Q3 source code yet, so that's about all the detail I can give you.   