My lighmap is weird!

[HunterSeeker]

I dont know what causes the problem, but you can see for yourself how it looks. How do I do to fix it?

 

[Ti133700N]

If a brush touches the floor, it will split the floor in many polys. (I think it's the wood railing we see on the left corner of the screen). To get rid of that, make that brush smaller (to leave a gap between the brush and the floor) and make another brush to fill the gap and tie it to a func_details entity. (In your case, you seem to already did that, make sure the bottom brush that touches the ground is a func_detail). Also, make sure that there are no brushes intersecting each other.