Show Posts
1
HARDWARE/SYSTEMS DISCUSSION / Retro machine entry corrections.
« on: July 15, 2010, 01:54:39 PM »
Hi guys,
I'm not sure how to comment on 'corrections' for retro machine entries. Obviously you've put a lot of work in it, but how does one post corrections?
For example, for the Vic-20; it says that it didn't suffer from colour clash. However, sometimes the VIC-20 did. Vic-20 graphics were supported via definable characters; so there's up to 22x23 character positions on the screen and the corresponding character bitmaps could be redefined. The colours worked the same way: a colour attribute area with 1 colour entry per character on the screen.
So, the 'high resolution' graphics had colour clashing. What you could do was get each character byte to be displayed in either 2 colour or 4 colour mode. In 4 colour mode each corresponding character bitmap scan was divided into 4x2-bit pixels: Ink, Paper, Auxiliary, Border. So, then you could have 4-colours per pixel at a 88x184 resolution (without colour clashing) and yet different character positions could have different ink and paper colours (which could still produce clashes).
Sorry for being so pedantic!
-cheers from snial @P
I'm not sure how to comment on 'corrections' for retro machine entries. Obviously you've put a lot of work in it, but how does one post corrections?
For example, for the Vic-20; it says that it didn't suffer from colour clash. However, sometimes the VIC-20 did. Vic-20 graphics were supported via definable characters; so there's up to 22x23 character positions on the screen and the corresponding character bitmaps could be redefined. The colours worked the same way: a colour attribute area with 1 colour entry per character on the screen.
So, the 'high resolution' graphics had colour clashing. What you could do was get each character byte to be displayed in either 2 colour or 4 colour mode. In 4 colour mode each corresponding character bitmap scan was divided into 4x2-bit pixels: Ink, Paper, Auxiliary, Border. So, then you could have 4-colours per pixel at a 88x184 resolution (without colour clashing) and yet different character positions could have different ink and paper colours (which could still produce clashes).
Sorry for being so pedantic!
-cheers from snial @P