straight from the horses mouth,

http://forum.1cpublishing.eu/showthread.php?t=31097

or if you can't be bothered to go over there,

Friday Update, April 13, 2012

Good day everyone!

We're very glad to announce that the beta patch is largely done. It's going into wide internal testing today, which will last through the weekend and probably a couple of days more. After we make sure nothing is amiss, we'll make the beta patch available to everyone

We're ready to release details on some of the improvements you'll see in the patch. Here we go:

Performance

We've performed a huge amount of work improving both average and minimum FPS in the game. Most recommended-spec machine will see a roughly double average FPS and a significant reduction in the micro-freezes that had previously plagued the game. Their frequency, duration, and overall FPS impact will be greatly reduced or completely redone.

Some of the changes include:

• Completely rewritten rended pipeline, which reduced CPU load;
• Rewritten texture manager, reducing stutter when loading new textures;
• Moved landscape geometry generator to its own CPU core, reducing stutters;
• Optimized tree code, reducing stutters when moving across landscape or rotating camera;
• Moved grass generator to its own CPU core, decreasing stutters during low-level flight;
• Moved all building and vehicle damage models to be pre-loaded, rather than dynamically loaded when they are destroyed. This increased mission loading times and memory usage, and reduced stutters when blowing things up;
• Improved multithreading in many other aspects of the code, improving minimal FPS on most multicore machines.

Finally, we need to mention the launcher.exe crashes. This was a very hard issue to address as it wasn't caused by a single 100% reproducible bug, but rather rare combinations of various uncommon events. The work described above, coupled with a huge volume of general bug-fixing performed, should have at least minimized the number of instances that lead to crashes. We haven't encountered one in months, but determining whether that'll be the case for the general player base will be one of the leading goals for this beta test.

Flight Model

We've performed a tremendous amount of work testing and improving flight models in the game, as well as improving various aircraft engines. We used actual pilot's notes and flight testing data during the process (thank you Sean!). Unfortunately some deeply-set limitations in the engine code do not allow us to minimize the margin of error at altitudes about 7 km (21,000 ft) where most aircraft begin to perform worse than their real-life counterparts. Fixing this requires more extensive code rework and will therefore only appear with the upcoming sequel. However at lower altitudes most flyables will perform much closer to real life. We also have to note that some aircraft, most notably Spitfire Mk.II, had better performance than the real thing. Others, especially their engines, had reduced performance. We've addressed these serious issues and made our planes fly much closer to the real thing.

More specifically:

G.50
Temperature models of the engine were wrong due to incorrect data. The engine could not get up to required power at all altitudes. We've also added +100 boost for WEP mode.

Spitfire Mk.II
The aircraft's speed performance was too good at all altitudes, sometimes 60 mph better than the real thing.

Spitfire Mk.I
Fixed the top speed dip above 18,000 ft.

Hurricane Mk.I
Speed performance was also too good at all altitudes, similar to the Spit II.

Blenheim Mk.IV
Had many problems with the engine model. The engine overheated at normal RPM, the plane could not get up to stated airspeed at all altitudes. Maximum allowed airspeed was too great, and the plane could get up to 560 mph in a dive. A huge amount of work was performed to improve the plane's FM and bring it up to speed.

For a better example, here's a comparison of the old and new speeds of the Fiat G.50. The data was taken by a special internal module that tests speeds at a range of altitudes using optimal engine settings. Human players will likely not be able to set their engine precisely the same way, or fly exactly level at the exact altitude, so testing this for yourselves may give you slightly different results. The vertical axis is the speed in kph, the horizontal is the top speed.


Artificial Intelligence

Partial list:
• Fixed some non-working orders, removed others from the list. There are no more orders available to the player that the AI does not follow.
• Added a request for available targets;
• Turned off friendly fire for ground battles (improving FPS);
• Added the ability to query current waypoint for scripts;
• Told AI pilots not to commit ritual suicide when their leader crash-lands;
• Fixed out of turn take offs for AI pilots;

And there's lots more!

Finally, we continue to introduce you to the upcoming sequels. Here's some more village landscapes, showing the few churches still left around 1940s Russia. Once again, these are all coming from an external team that is very eager to do a great job and please the community. We'd also like to remind you that parts of the landscape such as the grass and the trees are temporary placeholders and will definitely not be a part of the final landscape.

Have a great weekend!
Looking forward to next week, especially as it plays pretty **** good maxed out on my machine