AA setting and FPS

[Long Bow]

I thought I would just post this for some general info on Arma performance. This may be obvious to others but I found the other day that the Anti alasing setting has a rather significant impact on fps.

I have tried a variety of settings at two different resolutions one being 1280x1040 with mostly high settings except for shadows with some AA and AF at normal. The game played fairly smooth with manageable slow down in wooded areas and cities (dipping down to 18-20fps).

I then tried going to 1680x1050 (native resolution for my monitor) with a mix of normal and high with AA low and AF normal. I experinced fps drops down to 11fps in forests at times with an average around 14fps. Wich didn't suite my eyes. Every were else fps were fine dipping down to mid 20's or better.

I found going from low AA to dissabled made my fps in forests etc. jump to a minimum of 22fps wich was very smooth for my eyes. The only draw back in my opinion is the terrain at distance has some jaggies now that make the evironment look rather digital vs. with low AA it looked much more natural.

So basically going from low Anti alasing to none gives a rather large jump in FPS compared to going from normal AA to low AA.

[=Sarc=]

Everybody should know that AA is an expensive operation. The performance has improved over the years but new effects have made it difficult for some video cards to enable AA. Newer video cards are more likely able to handle AA but it's not always guaranteed to be smooth FPS with high resolution gaming. A lot of gamers are starting to switch to larger LCD monitors that have high native resolutions. This makes it more difficult to enable AA. However, AA was introduced as an alternative solution to high resolutions as a way to smooth jagged lines.

[chaka]

I find AA makes the most noticeable difference so I turn it up high and leave everything else on low or disabled. For me it looks great that way and runs smooth.

[Long Bow]

True Sark but I was surprised at how the game scaled with AA compared to other games I have played. The difference in fps between low and some of the higher settings was significantly less then between low and off. I had tried a variety of settings but kept AA to low and had trouble keeping smooth gameplay in dense areas. But with AA off it was a big jump and other settings were pushed up. Normally 2xAA isn't a big hit compared to off, Especially now that I have an 8800GTS, Arma just seems like a real beast to run no matter the card. My point was more to save people some headaches, trying to adjust all their other settings while keeping AA on low and never seeing a high enough baseline of fps or adjusting down everything else resulting in a poor image for the sake of fps.

Sark you are bang on with the high resolution gaming so many people neglect to take into account that a bigger screen can really impact performance, it happend to me going from 19" crt to 20.1" lcd. I have seen countless threads were people spout off that "I can run that game at max no problem..." yet fail to tell people that its at 1024x750.

[=Sarc=]

ArmA is quite a lush environment when you get into trees and bushes. It takes a lot to render alpha textures (what is commonly used for plants, basically textures with transparency) and adding AA to it is a big hit on performance. If you play a game on the Source engine, it's not so bad because there aren't so many alpha textures (usually chain link fences). A game like ArmA has a lot of alpha textures and even new cards can't handle it. Some have found disabling transparency AA or whatever it is called for the video card improves performance in trees and bushes.

[Long Bow]

I had heard about the transparency setting for AA and will look into that, I have left everything defualt in my nVidia CP as I read that the 16x.xx drivers can cause problems if adjusted?

Thanks for the explanation on the alpha textures. I have been playing around further on the single mission "Convoy" as it starts you very close to dense forest with a road through it. There was one spot I could go to and drop as low as 11fps while slowly scrolling my view through the forest over the road. I have started to overclock the card while keeping the same settings as before. The result is now I don't drop below 14fps at that scene and I still have more headroom to OC. Just those few extra fps (while only a few fps it does represent a significant increase in % of fps) make all the difference in my eyes. Hopefully Arma 2 will be optimized a bit more or have extensive adjustability to keep the game from becoming to demanding.

Thanks Sarc for the details.