The PhysX engine is the primary physics engine for the game. It is actually running no matter what gpu/cpu you have. But without the APEX option on, the effects which take more grunt to process are removed. APEX setting reenables this, and uses nVidia GPU to calculate all the physics. It enables more realistic cloth simulation (almost as if the material is thinner, it flaps even more, reacts to wind, etc) it enables some stunning particle physics. It will display up to 10,000 particles in Mafia 2 - and they don't dissapear quickly either. In fact i shot at a wall and filled the floor with particles so much that when i walked through it, i left a trailer of where i walked (feet pushed them out the way) - i then ran 100 meters down the road, had a gun fight with the cops, and walked back to where i shot the wall 2 or 3 minutes later and they were still there.
You also get PhysX tire smoke, which moves out the way when people/cars walk through it. It doesn't look THAT realistic, but then its the first time ive ever seen it used.
Here are some example screenshots showing off some Apex PhysX.....alsdo just a few other screenshots that I took. i have shadows on medium and everything else on high, including Apex PhysX.....runs ok on my rig.
And yes that trainer (well it's not really a trainer, it injects LUA code into the Mafia2.exe) gives you lots of weapons, Kar 98, M1 garand, Frag Grenade, Molotov, Revolver, MP40(i think), Grease gun, and a gun that looks like a cross between a PPS42 and a Sten. I can't remember it's real name. It also gives all the weapons that are actually obtainable in the demo.
First time I played the demo, about 6 minutes it it froze and errored out...something with the video...it was screwing up all kinds of visuals on my comp, I had to restart. When I restarted I played through successfully without issues, and I REALLY liked it. Was really wanting. Hoping to buy it soon. 12.7 sure is a short game though!
