Trees fading to billboards (Sprites)

Blitz3D Forums/Blitz3D Programming/Trees fading to billboards (Sprites)

Craig H. Nisbet(Posted 2004) [#1]
Has anyone ever made a tree system in Blitz that can make the distant tree switch to billboard sprites instead of fading out early. I've looked at a couple tree systems now and they both have the trees fading out as they go into the horison. Unfortunately, the trees can never get far enough away before they have to be faded out, or else your frame rate tanks. What I hate about that, is that it makes it look like there are no trees ever on the horison.

The Motorcross Madness 2 engine did the billboard sprite trick and it worked great! All they did was render a still of the tree in 3dsMax and put it on a sprite, and had it switch to it when it got to a certain distance. Then the sprite faded out eventually, but by that time, it was so far away, no one cared. The poping effect was hardly noticable!


Mustang(Posted 2004) [#2]
"Battlefield 1942" uses this method too... drawback is that alpha trees don't fog - very handy when you get lost flying around since non-fogged trees show where the damn island is :)


Seven(Posted 2004) [#3]
BlitzTree3D can do that, you just have to set the distance variables up correctly


Colvette(Posted 2004) [#4]
The technique is called "LOD" or "Level of Detail". It's used by a majority of commercial 3D games to one extent or another, and usually consists of 3 different levels of detail for each model.

This is essentially the same thing as mip-mapping, only on 3D models instead of textures. It's a pretty easy thing to do (theoretically) - you measure the distance from the view camera to each object in the scene, and the distance dictates which LOD you need to use.

As WickedRush says, you can probably do it with Blitz3D as is - my description above is if you want to code it yourself... :)