System:
Athlon XP 2400+ @ 2.13 GHz
Asus A7N266-C MB (nForce 1 415D chipset) using nForce 3.13 drivers.
Radeon 9800 (standard) video card with Cat 3.7 drivers
512 MB PC2100
1.993 is a definate improvement over 1.992. Framerates seem slightly higher than 1.991 (could not test 1.992 because of text issue). Wheels seem to spin correctly on P51 and Spit 9. Shadows look very good, but I noticed 2 minor issues with them:
1. Shadows are visible through wheels on the 2 planes I looked at.
2. Shadows visible through plane when in external view and zoomed out far enough.
Firing guns doesn't seem to effect framerate much, and tracers look better. Smoke is sometimes visible through plane body in external view at certain angles. (Very minor issue.)
Turning on anisotropic filtering in quality mode does not seem to badly blur text anymore. I tried turning it on because the trees sometimes seem to be only partially rendered. The tree "trunk" (x shaped flat polys) always show up, but the middle and tops of the trees don't appear until I'm very close to them. There is a very definate "line" across the screen where the rest of the trees are being filled in. It almost looks like the effect you get with bilinear filtering. I was hoping turning on anisotropic filtering would change this. If there was any effect, it was only that the "line" was pushed back some, but not enough where I could definately say it made a difference. (I'd say this is probably done intentionally to increase framerate.)
Other minor issues:
Zooming out far enough from plane (at least on p51) causes instrument panel to become transparent, letting you see through plane completely.
At certain angles certain terrain features seem to shimmer. It maybe partially a driver issue, but 1.992 was much worse than 1.993 is. 1.991 and original release did not have this issue as far as I can remember.
Propellor on all but p51 blocks icons and sun (including causing shadows from the blades). This is definately realistic, but causes annoying icon flicker. On the P51, the propellor sometimes seems to fade away after spanning on the runway. (Generally after quitting ah, restarting program and immediately spawning on runway will cause it for me.)
I can't seem to hit certain buildings with guns in the city, but I can definately collide with them.
Vehicles cannot leave hanger, the opening seems to be something you can collide with.
For some reason my framerate will occasionally drop from around 70 to 40 when flying low to the ground. (1280x1024 32bit color, 4x FSAA, 8x Aniso) The only commonality I can notice is that I've moved from a tree covered terrain tile to one of the grassy tiles with the small grass/bush objects on it. I'm not real sure why this is happening, as the framerate will recover eventually.
I've got to say that the hanger user interface is coming along nicely. About the only thing I notice here is that the bombs and drop tanks don't lift up onto the cart like the fuel drums do on that selector. (I'm sure you know about this already.)
New text is much more readable on the ammo counters and icons seem crisper. (As I said above, anisotropic filtering doesn't seem to blur this text anymore.)
AH 2 seems to be coming along very well, I'm enjoying testing each new version.