I've been messing with pygame for awhile and am having a blast!
Thanks for a great site, pygame.org people! And, I just got on this list and
already its been very helpful! I ran into a performance snag trying to blit a surface with
surface-alpha to a fullscreen display surface (trying to do a fade-to-black for
the screen). It works great (realtime) when the display is windowed. Lotsa
fun! But, when the display is fullscreen, each blit takes almost a second to
complete in 640x480 on a beefy machine. Now, I've read the pygame docs on surfaces and displays and
searched this list (finding some related discussions) and can't quite nail down
what my problem is. So, my question is: why does it take me so long to blit in
fullscreen mode? And, how can I create the surfaces in such a way that the
blit performs at realtime in both windowed and fullscreen mode? Here's some snatches of my code. I grabbed the important bits,
as it would be too much code to post all my classes in their entirety. …Set up windowed mode: pygame.display.set_mode((640, 480)) ...or set up fullscreen mode: pygame.display.set_mode((640, 480), pygame.FULLSCREEN |
pygame.HWSURFACE) ...creating the surface to do the fade: self._fadeSurface = pygame.Surface(size) self._fadeSurface.fill(color) self._fadeSurface.set_alpha(alpha) self._fadeSurface = self._fadeSurface.convert() ...blitting the fade surface to the display: self._targetSurface.blit(self._fadeSurface, (0, 0)) In windowed mode, pygame.display.Info() returns: <VideoInfo(hw = 1, wm = 1,video_mem = 238032 blit_hw = 1, blit_hw_CC = 1, blit_hw_A = 0, blit_sw = 1, blit_sw_CC = 1, blit_sw_A = 0, bitsize = 32, bytesize = 4, masks = (16711680, 65280, 255, 0), shifts = (16, 8, 0, 0), losses = (0, 0, 0, 8)> In fullscreen mode, pygame.display.Info() returns: <VideoInfo(hw = 1, wm = 1,video_mem = 244688 blit_hw = 1, blit_hw_CC = 1, blit_hw_A = 0, blit_sw = 1, blit_sw_CC = 1, blit_sw_A = 0, bitsize = 32, bytesize = 4, masks = (16711680, 65280, 255, 0), shifts = (16, 8, 0, 0), losses = (0, 0, 0, 8)> So, the alpha HW acceleration capabilities of the display in
either mode are the same. I do a convert() on the surface before blitting so
it's format should match the display's. Why is the blit so slow in one case
(fullscreen surface) and realtime in the other (windowed surface)? I'm sure
this has something to do with mismatches in surface modes, but I haven’t
been able to get a handle on the details. Thanks in advance... -Scott |