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Why is stretchblt so slow on x50v?

Posted:
Dec 14, 2004 @ 7:38pm
by bitbank
I thought that the X50v had hardware assisted bitblt/stretchblt. I am getting about 130-150fps for a 224x228 bitblt, but when I try to use stretchblt it drops to 5fps for a 448x456 (2x scale) blt. Is there something I'm missing?
Thanks,
Larry B.

Posted:
Dec 14, 2004 @ 7:39pm
by Kzinti
I guest it doesn't use hardware acceleration for the stretchblit? Try with a DDB, it properly will make a difference. But then you can't access the pixels...
Perhaps doing DIB-->DDB-->StretchBlt would be faster.

Posted:
Dec 14, 2004 @ 7:50pm
by bitbank
I'm blitting an 8-bit bitmap with an identity palette (direct color mapping). On my Toshiba e805 stretchblt goes at full frame rate, but the X50v is so slow you can see the screen painting like a "flow" from top to bottom.
L.B.

Posted:
Dec 14, 2004 @ 7:56pm
by Kzinti
Have you tried a 16 bpp bitmap? I have the feeling 8-bit palettized stechblits wasn't a priority.

Posted:
Dec 14, 2004 @ 8:35pm
by bitbank

Posted:
Dec 14, 2004 @ 10:51pm
by hm

Posted:
Dec 15, 2004 @ 12:52am
by Kzinti