Again a few questions. This time about terrain-engines. 1) I'm testing on GF4 and in some cases I get +20% increase of performace(becouse of early Z-outs) if I sort quadtree nodes in FtB order before I draw them. What other cards benifit from this? Is there any way you could actualy transverse quadtree in FtB order? 2) For basic geomipmapping you need to have links to node neighbours to know if node's neighbour has diferent LOD level so you can apply this edge error corection (to avoid cracks in terrain). Is there any other way around this since finding neghbours can be quite slow? 3) Is there way to use video card to create mipmamps of terrain for you. Like uploading original (2048*2048) map, using some nice minimization filter then downloading texture mipmaps? Is this possible? 4) Has anyone tried to implement texture splatting with adaptive quadtrees? How does his work? [edit: typos] You should never let your fears become the boundaries of your dreams. [edited by - _DarkWIng_ on September 15, 2002 7:21:50 AM]

Well, about number 2:

Calculating each nodes neighbour is not very slow at all. It''s really quite fast the way I have done it. Besides it''s precalculated anyway ( you would store pointers to the left right up and down terrain "sectors" ), so whats the problem?

Death of one is a tragedy, death of a million is just a statistic.

I came up with two algorithem, but they are both slow. Basicly I give every node unique ID. Then I search tree for node I'm looking for (I know how to calculate neighbours ID) for every node.... If you have any better idea just let me know

(When I say slow I'm thinking in terms of +20 seconds of precalculation for map with tree-depth of 8 or 9)

You should never let your fears become the boundaries of your dreams.

[edited by - _DarkWIng_ on September 15, 2002 12:52:56 PM]

Well, what I did is create a "matrix" of pointers to leaf nodes. Basically an array of all the leaf nodes. When I''m generating the tree, I generate the ID of that leaf based on it''s spactial postion ( 2D terms ), and goto that entry in the leaf-node-array, and set that entries pointer to the this node of the leaf. I then walk through the array, setting ID''s for the adjecent leaf nodes [ for instance, for index "i", the left node would be i-1, the right node i+1, etc... ]. This added maybe... a second onto my loading time. Maybe a bit less. For a 1029x1029 terrain. For a 2049x2049... it was about 2 seconds. Not much. Besides, you could precalculate it all and save it in a file. Then you can just load the relationships between the nodes when you load the terrain ( the id''s that is ).

Death of one is a tragedy, death of a million is just a statistic.

Nice idea. I'll try to code it tomorrow. But I don't know about saving this to file. How are you going to save memmory pointers? Now I have to get some sleep.

What about 1, 3 and 4? Any ideas... anyone?

[edited by - _DarkWIng_ on September 15, 2002 4:26:39 PM]

Ah I never meant saving memory pointers, but rather the ID''s, so that all you have to do is just grab the pointer from the leaf-matrix-array-thingy.

Death of one is a tragedy, death of a million is just a statistic.