When accessing the above URL the gameboy emulator listed above will have rounded corder. If the parameter is left out it will not, there seems to be a lot of redrawing taking place when it has rounded borders causing a significant decrease in performance.

Emulator seems to run twice (!!!!!) as fast without the rounded corners.

Happens on mac os 10.6 for me. Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0b8pre) Gecko/20101027 Firefox/4.0b8pre

Using rounded borders on an element with overflow:hidden causes a clipping region with rounded corners; that's potentially expensive. If you can put the overflow:hidden on a different element it would probably help.

I think the cario 1.10 update helps with this situation.

Timothy is working on this stuff.

Can we get some steps to reproduce? I guess I need the location of a ROM to test with.

Timothy, you can load roms in straight from your computer through the local file loading option (Uses the file api). Also, just Google for some homebrew or freeware roms. I think Tyrian 2000 is a freeware rom, read the article here to be sure: http://www.freewebs.com/worldtreegames/

Just a link to a freeware rom that would be good to use for testing would be great.

Thank you.

Is there some way I can get it to display fps or some other measure of the performance so I don't have to rely on my poor sense of perception?

Sadly not right now. I used to have fps measuring code in it. Anyways, make sure you uncheck auto frameskip in the settings, so it doesn't compensate for heavier rendering.

Please retest now that bug 628745 has been fixed.

Probably fixed by bug 628745. Please reopen if not.

Confirmed fixed (At least for me ("Works for me."))