Geometrical MipMapping terrains causes lag

General Discussion
#1

i am making a test terrain which is just a flat plane.
here is how i make it:

       self.terrain = GeoMipTerrain("terrain")
                self.terrain.setHeightfield(Filename(self.heightMapPath))
                self.terrain.setBruteforce(True)
                self.terrain.getRoot().reparentTo(render)
                self.terrain.generate()

But whenever the camera has the terrain in veiw it lowers the framerate a ton. is there somethign i can do to fix this. because if i “hand make” the terrain in blender even if its fairly detailed … it never did this so i dont know how im getting this immense framerate drop .

I have an ATI graphics card that isnt supported in fglrx so i had to use the open source driver but i havent had this problem before and the game ran just fine?

#2

It works just fine for every one else. Maybe you are setting insane sizes? Does brute force off change any thing?

Your next step would be Pstats.

#3

Hm, setting the min-level and block-size would be your best bet, in your case. Or, disable bruteforce and go for LOD.

#4

Even with bruteforce, blocksizes are important.

You have to fiddle with the Near/Far, blocksize and min-level parameters. I used Pstats and turned on wireframe rendering to get an idea of how many triangles I was getting out of my geomipterrain, adjusting until I had values that worked well.

It’s a balance between blocksize and detail level. Larger block sizes mean less chunks that can be visibility culled, and can require a lot of time to rebuild if your camera is moving around a lot. But smaller blocks require more shuffling for the LOD generator and raise the geom count, so it’s a trick finding an acceptable compromise.

#5

thanks guys i set the terrain chunk sizes bigger andnow i have no lag and it dosent take more than a millisecond to load :laughing:

#6

Interesting, I’d make a notice about that in the manual.

(When I’ll have time)