exxos's Atari, Amiga & retro forum

Inspired by this older forum post http://pixeljoint.com/forum/forum_posts.asp?TID=12795 and the great results they showed in the thread for Pixel art, I tried using an adapted form of this palette (aka Dawnbringer16) on the ST.

Realisations:
- The Dawnbringer16 palette uses 8 bit palette entries, which isn’t what is available on ST, STe/TT or Falcon hardware, so the palette values have to consider the 3 bit quantisation
- Some colors can’t be too different from ATARI’s default, esp. with low palette resolution (e.g. the grey & yellow values, white or the „desktop“ green), but you can get away with some changes (I think)

Would be great to get some feedback if this adapted palette works for other's too, or if you find some obstacles...

I've attached the palettes in GIMP format (8 bit per entry) for those who want to experiment on their own (the indexed mode in GIMP is a good tool for experimenting...). For those who just want to set the values in their color panel, these are the in values you'd have to set on the ST:

Idx
[0]: 7 7 7
[1]: 0 0 0
[2]: 6 2 2
[3]: 2 5 1
[4]: 2 3 6
[5]: 3 6 6
[6]: 7 6 2
[7]: 6 3 1
[8]: 5 5 5
[9]: 2 2 2
[10]: 4 2 1
[11]: 1 3 1
[12]: 1 1 3
[13]: 3 4 4
[14]: 6 5 4
[15]: 2 1 1

or STe/TT (with 4 bit palette entries):

Idx
[0]: 15 15 15
[1]: 1 1 1
[2]: 13 5 5
[3]: 5 11 3
[4]: 5 7 13
[5]: 7 13 13
[6]: 15 13 5
[7]: 13 7 3
[8]: 11 11 11
[9]: 5 5 5
[10]: 9 5 3
[11]: 3 7 3
[12]: 3 3 7
[13]: 7 9 9
[14]: 13 11 9
[15]: 5 3 3

Advantages
- works well with floyd steinberg dithering (esp. if the available resolution is higher like in the 16 color modes of ATARI TT or Falcon)
- works really well with Comic or Pixel art, even when just using nearest color matching (e.g. for background images)
- Good coverage of the luminance range (compared to ATARI's color selection)
- 3D UI effects (as used by MagiC/MagiC-PC/MagiCMac) still work
- considers the valid (limited) 8 bit sRGB range of TV sets (where values of {16,16,16} and everything below are black and where {235,235,235} and higher is white)
- palette values work with 8, 6, 4 & 3 bit hardware palettes (shifting the attached 8 bit color values down to the precision of the given hardware is enough) and delivers the same usable palette on all these devices (the TOS palettes differ from version to version and partially also depending on the machine).


Disadvantages (I’m aware of)
- No magenta in the palette although this can be emulated (to some extend with dithering) and is rather rare in image data
- Doesn’t utilise the extra precision of STe/TT/Falcon palette which could be used to get closer to the original values of the Dawnbringer16 palette
- Can’t compete with optimal (image specific) palettes or multi palette pictures (MPP) that switch palettes (potentially multiple times per line)

The zip with the GIMP format palettes:
and here's one of the images I used for testing:

Good choice of palette, I did my own adaptation for my game that you can see here https://www.exxosforum.co.uk/forum/viewt ... =61&t=3748

I do not have the same values, since I did the conversion from 8bits to 4bits values by dividing by $11 (17), (e.g. $ee / $11 = $e) and rounding the values around. Since I was on holidays without computer, I just built a map by hand :D

So, here is my palette. And in the github of the project (link in my signature), you will find some PI1 in the assets directory that uses the palette.

sporniket wrote: 25 Dec 2020 14:58 Good choice of palette, I did my own adaptation for my game that you can see here https://www.exxosforum.co.uk/forum/viewt ... =61&t=3748

I do not have the same values, since I did the conversion from 8bits to 4bits values by dividing by $11 (17), (e.g. $ee / $11 = $e) and rounding the values around. Since I was on holidays without computer, I just built a map by hand :D

So, here is my palette. And in the github of the project (link in my signature), you will find some PI1 in the assets directory that uses the palette.

Code: Select all

; Human readable palette for the app. It will be converted into STe color palette on startup.
; The palette of the stup is adapted from "DawnBringer's 16 Col Palette v1.0"
; see http://pixeljoint.com/forum/forum_posts.asp?TID=12795
; see https://lospec.com/palette-list/dawnbringer-16
; Colors 0, 1, 6 and 15 are put at index 1, 0, 2 and 3 resp. to optimize drawing of the sample game. (needs only
; bitplan 0 and 1 for drawing, thus 6 bitplans counting the masking.)
appPalette              dc.w                    $0423,$0112,$0c44,$0ded,$0336,$0555,$0843,$0362
                        dc.w                    $0776,$057c,$0c73,$0899,$06a3,$0ca9,$06bc,$0dc6

Cool project!

You utilized the extra precision of the STe palette (nice!), getting closer to the original values and had the freedom of "white" not being white in your palette - which doesn't work out in the desktop environment:
I've added the palette in GIMP format for experimentation:

thanks for the gimp palette