VICE palette

Boray · Post by **Boray** » Thu Jan 12, 2006 11:58 am

I've tried to make a palette file for VICE looking as close as possible to my vic-20 standing right beside the PC, so I can compare pretty well. I think I've got it pretty close. (You have to turn off PAL emulation in the options menu if you like to try it).

But what is the Dither value for? Anyone who knows?

/Anders

Code: Select all

#
# VICE Palette file
# Boray's 9v Vic w. Swedish keyboard 2006
#
# Syntax:
# Red Green Blue Dither
#

# Black
39 5C 44 F
# White
EE F7 E1 E
# Red
E7 66 5A 4
# Cyan
66 F9 C9 0
# Purple
E3 5B DA 8
# Green
60 EB 34 F
# Blue
63 6C D5 F
# Yellow
C8 DC 95 C
# Orange
B5 90 3A 4
# Light Orange
CC C9 A1 4
# Pink
D6 B7 A9 8
# Light Cyan
A5 E6 D2 4
# Light Purple
CB AE D1 8
# Light Green
AE F0 9A 8
# Light Blue
9F AB DB 8
# Light Yellow
D5 F1 B5 C

carlsson · Post by **carlsson** » Thu Jan 12, 2006 3:48 pm

VICE Manual wrote:DITHER is a 4-bit hexadecimal number specifying the pattern you want when rendering on a B/W display.

For comparison, this palette was derived by Pasi Ojala (Albert of Pu-239, VIMM etc). See also the slightly different colour definitions in the VIC-20 picture converter.

Code: Select all

# Black
00 00 00 0
# White
FF FF FF E
# Red
B4 18 18 4
# Cyan
4C E6 D8 C
# Purple
BC 29 CA 8
# Green
42 E4 36 4
# Blue
32 2A C8 4
# Yellow
D2 E1 26 C
# Orange
CA 5A 02 4
# Light Orange
DE AC 80 4
# Pink
DC 94 94 8
# Light Cyan
A5 F4 EC 4
# Light Purple
E0 9A E4 8
# Light Green
A0 F2 9A 8
# Light Blue
9C 92 E4 8
# Light Yellow
EF F8 9A C

It appears the brightness is cranked up rather much on your monitor, so black is rather grey. Pasi may have made a decision that black is black and white is white (which is not true on a real VIC-20, at least not PAL) and adopted the other colours accordingly.

carlsson · Post by **carlsson** » Thu Jan 12, 2006 4:08 pm

A small palette comparison, although not covering all colours:

No PAL emulation, so gamma, shade, blur, contrast etc doesn't matter.

Boray · Post by **Boray** » Fri Jan 13, 2006 7:25 am

Thanks! So I guess I can just forget about the dither value then...

Any idea why the pal-emulation option makes it look so strange?

/Anders

carlsson · Post by **carlsson** » Fri Jan 13, 2006 8:26 am

Not without reading the source code, but I believe PAL emulation calculates the colours based on gamma, shade, brightness etc. When using the default palette, PAL emulation looks somewhat OK, but as soon as you use a different palette, everything screws up so cyan turns light blue etc.

Boray · Post by **Boray** » Fri Jan 13, 2006 10:04 am

Btw, the color black can never become entirely black on an old TV or the Philips CM8833-II monitor I'm using, becuase the screen itself isn't black like it is on modern monitors. Maybe I have it set a little bright though, or my PC monitor is set darker than yours (which would result in a too bright palette).

/Anders

carlsson · Post by **carlsson** » Fri Jan 13, 2006 3:21 pm

One day I'll make my own palette. If I owned a video-in card to my PC, I could connect the VIC directly to it and take snapshots..