Dramatic frame rate improvement for certain AI traffic situations

[Tech Diver]

Before you get too excited, this only works for a specific situation as follows:


Background:
I didn't like the fact that the AI commercial stock aircraft that FXS displayed were fictitious airlines like World Travel, Orbit, Pacifica, etc. So using the excellent freeware tool called AI Flight Planner (AIFP), I changed the AI traffic to use only repaints as well as additional freeware aircraft that represented actual airlines.

The problem:
I generally keep my AI traffic set to about 75% and noticed that the frame rate at some airports was really low (about 7 fps instead of my usual 24). I also noticed that at those airports some of the aircraft "shimmered" due to poor anti-aliasing. I soon discovered that those aircraft did not have MIP maps included in their texture DDS files. This was pretty easy to determine visually and because their file size was roughly 1025 KB instead of 1366 KB (for stock aircraft). Additionally, most of my non-stock aircraft only had BMP files for their textures.

The fix:
Using a DDS plug-in for Paint Shop Pro, I opened the problematic DDS files then saved them as DDS type DXT3 with MIP maps. For those aircraft that used BMP texture files, I opened those files with the freeware tool DXTbmp Editor, flipped both image and alpha (VERY IMPORTANT to do both), them saved them as DDS type DXT3 with MIP maps. I then renamed the original BMP files to be something else so they would be ignored. Fortunately, FSX can use either type of file. By the way, you must do this with the night-lighting images as well. Internal cockpit images need not be converted.

The result:
My frame rates improved dramatically from a problematic 7 fps to about 18 and sometimes even my usual smooth 24. Additionally, my aircraft no longer shimmer and appear nice at all distances. Whether or not I include aircraft as part of my AI fleet, I now always make sure that their textures are in DDS type DXT3 format with MIP maps. Even when flying a single aircraft I defintely notice a frame rate improvement when it comes to the external views.

Note:
Perhaps this problem was only relevant to me because I use an ATI 4870 graphics card and I know that various NVidia cards do a much better job at hardware-based anti-aliasing. But if you are in the same situation as me, give this a try.

Peter

[Thai09]

Great advise thanks!

But I did something else:

Removed the default AI completely, and now only use Just Flight X, better performance that way.