Re: A82: 6 by x sprite routines
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Re: A82: 6 by x sprite routines
Could another Implementation be to more easily put a 12x12 tile TileMap to
the screen, so then you can work in halves of tiles, and they be aligned,
rather than some of those 12x12 sprites in a normal 8x8 system be
Non-Aligned? Just wondering...
Jason_K
In a message dated 8/2/99 10:17:15 PM Central Daylight Time,
j.wazny@ugrad.unimelb.edu.au writes:
> I don't think it's all that useful since you still have to write a whole
> byte to the port (obviously), so you're losing 2bits of potential
> information. The other thing is that you'd have to write directly to the
> data port, instead of using some bitplane in addressable ram (eg.
> GRAPH_MEM), which tends to get awkward if you want to be able to easily
> manipulate it later on, or if you don't plan on displaying the data
> strictly in the order that you receive it; ie. direct cursor manipulation
> is messy, especially things like "backspacing" it after a write when
> you've got so few registers for quick temp. storage. The alternative, to
> write a CR_GRBCopy-esque function for the 6bit mode is terribly wasteful
> when you consider you'd need 1024 bytes as opposed to 768 bytes in the 8
> bit case. Even if you "compacted" all those 6bit chunks into fewer 8bit
> bytes, you'd still be faced with the problem of shifting them back into
> position before the port write.
> On the other hand of course, if for some reason, you needed to align 6bit
> wide bitmaps so that they lie directly side-by-side (text, perhaps?), it
> could be at least an "interesting" alternative to boring old shifting.
>
> -Jeremy
> ... and to answer your question: I don't know.
>
>
> On Mon, 2 Aug 1999, Kouri wrote:
>
> >
> > If anyone has read the newest version of 82-PORTS.TXT, Dines says
> something about changing the display controller mode so that you can use 16
> columns of 6 pixel-wide "bytes" instead of 12 columns of 8 pixel-wide
"bytes."
> I was just wondering if anyone has actually made a routine that utilizes
> this new information. Anyone?
> >
> >
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