StretchBlt slow, can I use directx somehow?

[darwen]

MMX makes use of the floating point processor to do things in parallel (the FPU).

The 'emms' instruction basically restores the FPU's registers back to their original values after MMX instructions.

However the overhead in using the floating point processor is outweighed by the multiple instruction pipelines in modern day processors providing the source assembly is designed to take advantage of this. Apparently - according to my reasearch at any rate.

If you're using DirectX then you're using bitmap manipulation capabilities on the graphics card which will of course be very much faster.

However : a word of warning. As I believe I've already said, DirectX9 assumes that the bitmap stretching and other functions are provided by the hardware and doesn't have a software fallback.

If you use DirectX9 you must be aware that anyone using a graphics card which doesn't support hardware stretching (say earlier than an NVidia 64Mb card) will not be able to run your application.

Darwen.