TC wrote:

> BTW: my first computer was a VIC with a whole 5 kB main memory. To draw 
> complex graphics (like a monochrome sine curve ;-) you had to fill the 
> video memory with a sequence of ASCII chars, map the dot-matrix for 
> those chars (8x16 dots) to memory, and then redefine the respective 
> rectangular dot-matrices so that a graphical output would happen. If you 
> have done this, everything windows throws at you is just a minor 
> nuisance ;-)

mmm. 8 bit computing ;)

A long time ago, I did some work with a Gamboy Color game, which aside 
from the Z80 clone processor it was using was kind of similar to the 
NES. There's a reason the backgrounds are tile-based on those consoles. ;)

I'm more familiar with how the NES graphics system worked, than I am the 
GBC's graphics system (I had access to Nintendo's developer 
documentation, the NES documentation fascinated me, since I (mis)spent a 
lot of time playing NES games) essentially you had a character table 
that had the sprites defined, each character comprised of four colors, 
8x8 so, each scanline of the character was 16 bits wide. You defined 
those characters, then referenced them in a table, along with some 
flags, one of which was which of the 4 loaded palettes to use when 
drawing that character on screen. The table was 2 screens, either 
vertical or horizontal (and could be scrolled either way, there was also 
a special trick to scroll both vertically and horizontally.) I want to 
say there were 2 bytes per entry, one was the block, the other was the 
flags. Sprites were also handled by the same character table/palette 
system.

Wow... that was a huge digression.. ahem.. ;)


-- 
~Mike

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