Just because a phone gets ICS—be it officially or unofficially—doesn’t mean that the hardware is ready to receive it. In some cases, it takes a mod or a tweak to get things rolling. And in most cases, you can get an ICS ROM working just as well, if not better, than its Gingerbread counterpart. This is the case for the Sony Xperia Arc, where hardware acceleration was not cutting it, so a software rendering patch was brought in to improve things.
XDA Forum Member tkymgr has posted a software rendering patch which actually makes ICS run a little better. Of course, this comes at the at the price of hardware acceleration. The patch, which is to be applied by decompiling the framework.jar and replacing a couple of smali files, actually disables hardware rendering and instead opts to go with software rendering. Surprisingly, this actually makes the stock ICS ROMs run more smoothly, as thus far everyone who’s tried it has reported positive results to some extent. This ironic because hardware rendering of 2D GUI functions is generally always faster than software rendering.
Many think that Sony made a mistake somewhere, and that’s why hardware rendering doesn’t quite do the trick. Since the problem may stem from a kernel issue or, more likely, bad GPU drivers, that opinion seems quite likely. In any case, this patch will actually break the Chrome Browser for those who have it, as the app requires HW Acceleration to work. Any other apps that require hardware acceleration can be assumed to no longer work as well once the patch is applied.
So for anyone who wants a better running ICS ROM and doesn’t mind hardware acceleration being turned off, you can head on over the original thread to get started.