Why is stretchblt so slow on x50v?

[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.

[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.

[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.

[Kzinti]

Have you tried a 16 bpp bitmap? I have the feeling 8-bit palettized stechblits wasn't a priority.

[bitbank]

[hm]

[Kzinti]