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Re: Apple II VGA Video Generator Card Project



bieling@terra.es wrote:

But "takes longer" is not a measure of drawing speed. The space, measured
in pixels, is missing in this equation : (drawing speed) = (pixels drawn)
/ (time to draw them).

There is another factor to the equation - the memory architecture of the frame buffer. The A2 video memory map is, from a software point of view, quite simply ghastly! The calculations to find a video pixel memory address are orders of magnitude greater than simply shifting an address or even being able to simply increment an address when crossing a byte boundary.

Any 'enhanced' video mode would most likely have a much, much nicer addressing scheme for the frame buffer.

And that will make a difference - particularly in BASIC.

Regards,

--
|              Mark McDougall                | "Electrical Engineers do it
|  <http://members.iinet.net.au/~msmcdoug>   |   with less resistance!"