I have checked, https://www.virtualbox.org/ticket/4777
and it seems there is no bug... today. (bug was reported 12 years ago)
I am using doc at:
https://web.archive.org/web/20081211174813/http://docs.ruudkoot.nl/vbe20.txt
VBox, return VBE 2.0, so it does support AH=9 to set/get palette.
And I verified that it does it in text mode.
The author say that capabilities is 1, and that it means it does not support
VGA.
I confirm capabilities, is 1 (first byte is 1, other are 0).
This means:
" The Capabilities field indicates the support of specific features in
the graphics environment. The bits are defined as follows:
D0 = 0 DAC is fixed width, with 6 bits per primary color
= 1 DAC width is switchable to 8 bits per primary color
D1 = 0 Controller is VGA compatible
= 1 Controller is not VGA compatible
D2 = 0 Normal RAMDAC operation
= 1 When programming large blocks of information to the
RAMDAC use blank bit in Function 09h. i.e. RAMDAC
recommends programming during blank period only.
D3-31 = Reserved"
So D0=1 means DAC width is switchable to 8 bits per primary color
And D1=0 which means VGA compatible.
I suspect when D0=1 it is more important to use VBE AH=9 to get/set palette
rather than the VGA function:
https://fd.lod.bz/rbil/interrup/video/100b_bh01.html
I did not check capabilities return by QEMU...
My vague hypothesis is that the game use VGA functions, rather than VBE
function to set palette,
and that it matters because D0=1... and I make the assumption D0=0 for QEMU._______________________________________________
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