VBXE Text Mode question(s)

[+Stephen]

I have a few questions about the text mode.

 

1. If I am understanding the documentation properly, there is no way to have completely independent foreground and background colours in text.  The foreground colour can be 0-127, and if appropriate bits are set, background can be 128-255, BUT it will always be foreground colour + 128.  Am I correct in this assumption?
2. There is mention of "in 128 or 16+8 colours" but I cannot find an explanation of that.
3. General question - can the Colour Map be combined with Text or Graphics modes, or does the Colour map only affect the standard GTIA.

 

What I am needing to do, is have full independent control of foreground and background using text.  I've thought about making the palette have each colour with a corresponding colour+128 but there's not enough entries to do this.  The only other way I can think to do this would be to use the 640 pixel hi-res graphics mode and write my own routine to blit text, but then I am limited to 16 colour mode.  That would meet my needs as I only need 16 colours of text, but this means a full screen is then 64kB or more as opposed to 4kB.

 

Thanks for any info.

[bfollett]

I know nothing about programming the VBXE but I did find a post on this forum where it appears you can have independent foreground and background colors with text:

 

Full Color ANSI VBXE terminal in the works - Atari 8-Bit Computers - AtariAge Forums

 

There's a video demo in post #12.

 

Bob

 

 

[+Stephen]

2 minutes ago, bfollett said:

I know nothing about programming the VBXE but I did find a post on this forum where it appears you can have independent foreground and background colors with text:

 

Full Color ANSI VBXE terminal in the works - Atari 8-Bit Computers - AtariAge Forums

 

There's a video demo in post #12.

 

Bob

Thanks - this must be the 16 + 8 mode the documentation was referring to (16 foreground, 8 background).  I'll re-read to see what I must have missed.

[Rybags]

Atrribute Map allows selection of independent palette for Antic and VBXE seperately per cell - though the minimum cell is 8 Antic hires pixels which is 2 80-col characters.

[phaeron]

You don't need special hardware support to do 16+8. The hardware allows 128 unique (fore, back) color combinations to be set, so you can just program one of the palettes so that the foreground color only changes on 4 of the bits and the background color only changes on the other 3 bits. 16 foreground * 8 background = 128 total color pairs.

 

The attribute map should be able to do 80 columns if you drive it from a mode A playfield on ANTIC -- alternate columns between PF0 and PF1 in the playfield to select between the PF0 and PF1 bytes in a 40x24 attribute map. Run the text overlay layer on top of that with background transparent and the result should be completely independent 128 foreground and 256 background colors per character.

 

[+Stephen]

Thanks guys - I kept plugging away and I finally have something to show.