"SSwift, I am dissapointed at the results that you have found, but would you not get a comparable performance hit from not having unseen meshes culled?"
Let me make a clarification.
For each surface of each entity, regardless of whether you use copyentity or copymesh, you get a speed hit.
However, you also get a speed hit for the number of polygons that are visible at once.
There is a sweet-spot where selectively combining entities together and keeping them seperate gives you the best performance.
I can't tell you where this sweet spot is, but I can tell you that it's likely to be vastly different from card to card.
What I suggest is combinig entities which are close to eachother.
The test that I did a while back was a test to see how many trees I could pack onto a terrain at once while still maintaining a framerate greater than 20fps.
With individual entities, the number of trees I could have at once was very low.
However, I discovered that I could make "clumps" of trees that were near eahtoher into a single mesh with a single surface, and in doing so I was able to get 100,000 trees onto my terrain at once.
I may have been able to put even more if I worked at it some more to tweak the number of trees in each mesh.
Of course I did not have 100,000 trees visible at once. I had a fraction of that visible at once. The point was that as you walked around this huge terrain lots of trees were always in view.
Btw, I used entityautofade in my demo. I tried to do an octree, but I found it was very slow. I'm not sure why. It shouldn't have been.
Oh and also, the groups of trees I used were like 50-100 trees in a group. That seemed to be the optimal number for a large fairly open terrain with trees that only went about a half mile into the distance. My trees were just two planes each though. WIth more detailed trees you'd have to use less obviously.
Let me make a clarification.
For each surface of each entity, regardless of whether you use copyentity or copymesh, you get a speed hit.
However, you also get a speed hit for the number of polygons that are visible at once.
There is a sweet-spot where selectively combining entities together and keeping them seperate gives you the best performance.
I can't tell you where this sweet spot is, but I can tell you that it's likely to be vastly different from card to card.
What I suggest is combinig entities which are close to eachother.
The test that I did a while back was a test to see how many trees I could pack onto a terrain at once while still maintaining a framerate greater than 20fps.
With individual entities, the number of trees I could have at once was very low.
However, I discovered that I could make "clumps" of trees that were near eahtoher into a single mesh with a single surface, and in doing so I was able to get 100,000 trees onto my terrain at once.
I may have been able to put even more if I worked at it some more to tweak the number of trees in each mesh.
Of course I did not have 100,000 trees visible at once. I had a fraction of that visible at once. The point was that as you walked around this huge terrain lots of trees were always in view.
Btw, I used entityautofade in my demo. I tried to do an octree, but I found it was very slow. I'm not sure why. It shouldn't have been.
Oh and also, the groups of trees I used were like 50-100 trees in a group. That seemed to be the optimal number for a large fairly open terrain with trees that only went about a half mile into the distance. My trees were just two planes each though. WIth more detailed trees you'd have to use less obviously.