Weird, but I think it is related to a problem with window sizing.
Making the window smaller appears to always work. Making a window bigger sometimes leaves the GL canvas a bit smaller than the window… though it appears that you are rendering your scene as if it is the same size of the window (e.g. the gun is mostly missing because the lower right corner is empty)
No, there isn’t. My rasterizer does gouraud-shaded, zbuffered and perpective corrected, filtered texture-mapping all the time. There’s no way to disable it (except for the filtering). If you want to (ab)use a software rasterizer for occlusion culling, you have to write your own, because (as you mentioned) all you need is Z (or better 1/Z to get the perspective correction of Z for free)…you don’t even have to have a color buffer, don’t you?
Software I get 10-12fps on my Athlon 1.33 GF2gts 32mb.
(not the latest drivers, as they don’t work with C&C Generals :/)
when switching to LWJGL, i get :-
Software renderer disposed
Current mode:640 x 480 x 16 @75Hz
[ Wed Mar 03 12:00:33 GMT 2004 ] - ERROR: Can't set videomode - try different settings!
java.lang.Exception: No window.
at org.lwjgl.input.Keyboard.nCreate(Native Method)
at org.lwjgl.input.Keyboard.create(Unknown Source)
at JPCTDemoWS.switchOptions(Unknown Source)
at JPCTDemoWS.gameLoop(Unknown Source)
at JPCTDemoWS.<init>(Unknown Source)
at JPCTDemoWS.main(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.sun.javaws.Launcher.executeApplication(Unknown Source)
at com.sun.javaws.Launcher.executeMainClass(Unknown Source)
at com.sun.javaws.Launcher.continueLaunch(Unknown Source)
at com.sun.javaws.Launcher.handleApplicationDesc(Unknown Source)
at com.sun.javaws.Launcher.handleLaunchFile(Unknown Source)
at com.sun.javaws.Launcher.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Oh, and it also leaves a rogue process going, which eats all my CPU time. I have to kill that manually.