PALETTE: C&C 6bit .pal import produces incorrect colors

[Metadorius]

When I convert to PNG with my script:

When I open the pal directly:

[Metadorius]

import png
import struct


fname = input("*.pal to convert: ")


with open(fname, "rb") as pal:
    data = pal.read(768)
    palette = list(struct.unpack("768B", data))
    palette = (palette, )

with open(fname + ".png", "wb") as pngpal:
    w = png.Writer(width=256, height=1, bitdepth=6, greyscale=False)
    w.write(pngpal, palette)

Here's the conversion script in Python, requires pypng.

[mgerhardy]

For my future me ;): This is a C&C pal file.

Can you maybe please attach the pal file for testing purposes?

[Metadorius]

Sure thing.
unitsno.zip

Also here's the reference to the format:
https://modenc.renegadeprojects.com/PAL

[mgerhardy]

Thanks a lot - the reading is fixed now by trying to identify whether the pal file is 6 bit only. The problem here is that the pal file is not only used by C&C as 6 bit value - but also by other tools/games that are using 8 bit values.

The issue is not yet resolved for writing.

This is most likely becoming a cvar to control the behavior and to let it work for both cases.

[Metadorius]

How about an option/toggle for specifying bit depth? Or perhaps having multiple .pal formats to choose from?

[mgerhardy]

this is the case now - if you select the RGB Palette (*.pal) in the file filter list, you get this option

[mgerhardy]

this is with the 6 bit option activated

[Metadorius]

Can confirm the option works. I think the name would not be intuitive to C&C users though, as they don't have an idea what is 6-bit colors. Perhaps the best thing to do would be to have it as a separate file format, as you already do with JASC palette? Then if the user selected the pal file - ask which of the formats is this file in when opening/saving (if all formats are selected for filtering the view).

[mgerhardy]

see #536 - the idea could also be to load the 6bit colors in the c&c view mode