SpeedTree LOD & Optimization for UDK

TychoVII

I made a post at the UDK forums, but their community doesn't seem to be as lively as this one, so I'm hoping somebody here may be able to help.

So, I made a tree and imported it into the UDK.

Now, while in the editor I preview the level and use the command 'Stat Engine' to see how many static mesh triangles are being displayed. When I zoom away from my tree, this number does not change. Does this mean that the LODing is not working? Looking at the tree, it doesn't look like it's getting LOD'd, but it's difficult to tell. How do I know if it's working? If it's not working, why not?

I followed Raven's setup for LODing in his SpeedTree video, but it doesn't go into any depth about the subject. Anybody have any ideas?


On a sidenote. Hourence's website says that using opacitymask is more efficient than using transparency when it comes to masking transparent images. Below is a comparison between the two.

LEFT: OpacityMask
RIGHT: Transparency



To me it looks like Transparency is more efficient from a shader complexity view. What do you guys think?

commander_keen

Soft alpha is super expensive in large environments. Objects with soft alpha need to be sorted correctly which breaks up the (hopefully optimized) draw call queue, plus you get the overhead of actually calculating the sorting order of the objects. For something used as much as tree you should never use soft alpha.