I wonder how can i use 3d textures for adding detail map to a landscape... for example i can have my w text coord to be an interval, and then apply the proper "height" of the 3d texture. For example for heights [0, 100] grass, [100,200] rocks, ect... Is it actually applicable? or is it simply better to use multitexturing / blending to give such an effect? Wich one will be the most hardware friendly? such 3d textures can be blended? thanx... Cybird

i think you would make one layer for each type, so grass would be a layer, rocks would be a layer. so that specific texture would have dimensions X by Y by 2. then, to use it, the 3rd texture coord would be the layer. so if you made the 3rd texture coord 0, it would be all grass. 1, it would be all rock, and 0-1 is interpolated in between.

3 layers, 0 - .33 is the first layer, .33 to .66 is the second, .66 to 1 is the third. so you would set the 3rd coordinate of the texture coords in the terrain to what layer you would want it to use.

Interesting idea...

I don''t see anything wrong with it, assuming you''re willing to limit yourself to HW that supports volume textures. Of course you''d need a fallback technique in other cases.

You might not want to directly feed elevation into the w coordinate. Otherwise at an elevation of 75 you''d be blending 75% grass with 25% rocks. It might be better if the blend occurs in, say, the 95-105 elevation range. 95 = 100% grass, 100 = 50/50, 105 = 100% rocks, something like that.

Give it a try, I''d like to know how it works.