>>Perhaps we wouldn't need any more than 320x200 anyway. Instead of doubling
>>the pixels to create 160x200, we just switch from venetian blinds to
>>vertical blinds and put the even-numbered scanlines on even-numbered
>>columns. Piece of cake.
Er, _possibly_. Definitely easy to code. Problem is that the gaps in the
blinds would be almost twice as large (we have to fit fewer pixels in a
larger space horizontally than vertically.) Dunno how good it would
look...
>Too cool !! But if you're running in a tweaked mode, the difference between
>the even pixels and the odd pixels is merely a setting in a bank-switch
>register. It just doesn't get much easier than that. May even run faster
>than mode 13.
No, it's still quite complicated, and definitely not faster than mode 13h.
In mode 13h, it's three assembler instructions per pixel - load into
register, store to memory, increment memory counter. With mode-X, each
pair of pixels would be: load into register, store to video memory, load
next pixel into register, store to system memory, increment counter, then
at the end of the scanline, it's another load/store/inc counter cycle for
each pair - total, eight instructions for two pixels plus about another ten
per scanline to bankswitch. Not much slower, but tricky to code (but I'm
up for a challenge - someone let me try to hack their emulator to do it :)
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