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Does QEMU only support 24bits per pixel ? I want to use 32 bits per pixel

abcd1996 wrote:Does QEMU only support 24bits per pixel ? I want to use 32 bits per pixel

Try running QEMU with the -vga std parameter.

omarrx024 wrote:

abcd1996 wrote:Does QEMU only support 24bits per pixel ? I want to use 32 bits per pixel

Try running QEMU with the -vga std parameter.

Thanks! I just found the same suggestion on google.
edit:
The bpp in mode_info struct is still 24

abcd1996 wrote:Thanks! I just found the same suggestion on google.
Why are they not doing this for default

From my personal experience, QEMU 2.0+ does this by default on Linux, but all versions of QEMU for Windows default to -vga cirrus, which only supports true color as a 24-bit mode.

omarrx024 wrote:

abcd1996 wrote:Thanks! I just found the same suggestion on google.
Why are they not doing this for default

From my personal experience, QEMU 2.0+ does this by default on Linux, but all versions of QEMU for Windows default to -vga cirrus, which only supports true color as a 24-bit mode.

The bpp in mode_info struct is still 24

-vga qxl doesn't work either, 0x118 mode still has bpp24

abcd1996 wrote:The bpp in mode_info struct is still 24

-vga qxl doesn't work either, 0x118 mode still has bpp24

Very common mistake: NEVER, EVER assume video mode numbers.
QEMU with -vga std supports 32-bit modes but the mode number is not 0x118. Asking the BIOS for supported video modes is your homework today.
I've written this tutorial on VESA back then. It should clarify things and has example code for reference.

Don't use VBE 1.0 mode numbers. They are not guaranteed to work for anything other than ancient backwards compatibility, if at all.

Search for high resolution modes by looping through the appropriate VBE calls yourself.

omarrx024 wrote:

abcd1996 wrote:The bpp in mode_info struct is still 24

-vga qxl doesn't work either, 0x118 mode still has bpp24

Very common mistake: NEVER, EVER assume video mode numbers.
QEMU with -vga std supports 32-bit modes but the mode number is not 0x118. Asking the BIOS for supported video modes is your homework today.
I've written this tutorial on VESA back then. It should clarify things and has example code for reference.

I've read your articles before(many times) , but still assume the mode number because I was lazy. i will do it now

Kazinsal wrote:Don't use VBE 1.0 mode numbers. They are not guaranteed to work for anything other than ancient backwards compatibility, if at all.

Search for high resolution modes by looping through the appropriate VBE calls yourself.

Thanks Kazinsal !!