BestModeID amd BestCModeIDTags 32bit mode bug ?

@All
Find out today that while i have in my sreenmodes 8, 16 and 32 bit modes, using BestModeID from graphics.library and BestCModeIDTags from cybergraphics.library with depth greater than 24 simple return 0xffffffff as modeid.

The only function which behave correctly and return the correct mode is p96BestModeIDTags from picasso96.

Can somebody double checked that ?

@kas1e

#ram:BestModeGFX 1280 1024 32
No valid screen mode found!

#ram:BestModeGFX 1280 1024 24
Using graphics.library 54.252 (16.1.2022)
Width....: 1280
Height...: 1024
Depth....: 24
DisplayID: 0x50081300
#

See BZ entry #8828

@Javier
Quote:

Intersting.. SSolie says there that "there is no such things as 32bit, only 24bit", but then why we have 32 bit in list of screenmodes, and every game able to use it as 32 bit. Maybe it was like this back in days when there wasn't RadeonHD/RX drivers ?

@kas1e
nope, there isn't anything called 32-bit when it comes to graphics in screenmodes.
what everybody calls 32-bit is really 24-bit with an additional 8 -bit alpha channel that is why you see OxAARRGGBB if you had 32bit those remaining 8 bits would have to be divided between 3 color channels, and that is impossible.

@trgswe
Sure, its all known that 24 RGB and 8 alpha, just why it need to bother developer who want to requere list of screenmodes which is marked as 32 bits ? Who care that this is 24 + 8, if it listen as 32, so why graphics functions for "get best mode ID" do not return 32 bit ones ?

Let the deep details about "that not real 32, but 24 + 8" (which is 32), but you question 32 mode, why not return 32 mode.

@kas1e

Picasso96 15bit modes use 16bit data