
Being a BeOS user (a purely desktop system) and because I code under Linux, I see
XFree86 (v4.1 on my machine) as a user and as a developper. And this is where the problem lies. My Gnome or KDE desktops are slow in comparison with other operating systems, but XFree86, the 'engine' behind these desktops, proves me that it's not. Let's look at what I have in front of me: a dual Pentium III at 933Mhz with 512MB of memory, a Radeon 32 AIW, a modified Mandrake 8.0 powered by kernel 2.4.18.
You might have read an article quoted on /., which points out the fact that our video cards are NOT optimized for system->video memory transfer. The AGP port doesn't help, since the manufacturer don't bother about memory transfer from outside.
Guillaume is right when he says that blitting in video memory is really fast. But when you have no more video mem, or when you want to activate opengl, what are the perfs?
On the other hand, what will the perfs of BlueEyedOS be when you will have to draw lines? I understand you want to blit everything. But this way, you will have perf issues when drawing lines (CAO).