Burning rubber is displayed in color even though the CPC is set to black and white

[cpcbegin]

You can see on this video at this point.

I try the lastest code of april 9, 2021 compiled in GNU/Linux (Ubuntu Mate 20.04).

[ColinPitrat]

Interesting. I checked and this is an old bug, not introduced by the migration to SDL2.

[ColinPitrat]

The problem is that in asic.cpp, when we set the palette, we do not check CPC.scr_tube.
There's actually a TODO for it:

// TODO: deduplicate with code in video_set_palette + make it work in monochrome

[ColinPitrat]

The problem is that the Plus mode offers 4096 colors instead of just 32, so we need some generic code to convert the colors.
Fortunately, #135 provides just that.
Currently we support two green modes but with the Plus, we may have to force the libretro one ...
Or manage to find a formula that reproduces the original Caprice32 green mode.