Stefan Doesinger stefan@codeweavers.com wrote:
This obsolettes the 15 bpp bitmap and 16 bpp screen compatibility since 15 bpp bitmaps do not exist.
15 bpp bitmaps do exist. According to the Feng Yuan's book that depends on the driver and hardware.
Am Mittwoch, 12. Dezember 2007 10:15:32 schrieb Dmitry Timoshkov:
Stefan Doesinger stefan@codeweavers.com wrote:
This obsolettes the 15 bpp bitmap and 16 bpp screen compatibility since 15 bpp bitmaps do not exist.
15 bpp bitmaps do exist. According to the Feng Yuan's book that depends on the driver and hardware.
Do you have any driver / hardware where we could verify or falsify that?
"Stefan Dösinger" stefan@codeweavers.com wrote:
Stefan Doesinger stefan@codeweavers.com wrote:
This obsolettes the 15 bpp bitmap and 16 bpp screen compatibility since 15 bpp bitmaps do not exist.
15 bpp bitmaps do exist. According to the Feng Yuan's book that depends on the driver and hardware.
Do you have any driver / hardware where we could verify or falsify that?
No, I don't. I'd say that even with a technically 15 bpp screen depth video memory organization a driver would still say "16" in the user visible settings to avoid a possible user confusion, but report "15" on the API level.
A google search "15 bpp screen depth site:microsoft.com" finds some info about this.
Am Mittwoch, 12. Dezember 2007 16:15:11 schrieb Dmitry Timoshkov:
No, I don't. I'd say that even with a technically 15 bpp screen depth video memory organization a driver would still say "16" in the user visible settings to avoid a possible user confusion, but report "15" on the API level.
A google search "15 bpp screen depth site:microsoft.com" finds some info about this.
Most of the pages found are about Windows CE / Windows Mobile, and others contain the words "15" and "bpp" without any connection between them. The only interesting bit I found was the first hit, which states that "15 bpp" translates to "32,768 (32K) colors".
However, some pages which look Windows Mobile related suggst that the remote desktop feature can be configured to use 15 bpp. Maybe we can set a terminal server into that mode and see what the API returns?
Another disturbing thing about 15 bpp is the complete lack of 15 bpp formats in the DirectX API.
Also, if Windows supports 15 bpp displays, why does a normal Windows refuse to create 15 bpp bitmaps? Even if it is running at 8, 16, 24 or 32 bpp, it accepts 1, 4, 8, 16, 24 and 32 bit bitmaps, but never 15 bit ones.
Perhaps 15 bpp is one of the features that were once planned, so Feng Juan wrote about it, but no driver uses it and it is dead and nonfunctional in all Windows versions?
On Dec 12, 2007 2:15 AM, Dmitry Timoshkov dmitry@codeweavers.com wrote:
Stefan Doesinger stefan@codeweavers.com wrote:
This obsolettes the 15 bpp bitmap and 16 bpp screen compatibility since 15 bpp bitmaps do not exist.
15 bpp bitmaps do exist. According to the Feng Yuan's book that depends on the driver and hardware.
I almost bought that book, but got another one, unfortunately. There are "15-bpp" bitmaps, but they are padded with an extra bit. Windows does not have true 15-bpp aligned bitmaps. There are graphics cards that do 15-bpp too, whether they do not have 16-bit screen depths I don't know. I think windows obfuscates them and calls them all 16-bit in gdi whether it does 15 or 16, and then it is up to the driver to do it correctly. Unfortunately I do not have a card anymore that can do 15-bit modes.
Anyway if you try to select in a bitmap that says it is 15-bpp in the format on windows, it will fail. Wine does not, and we probably need test cases like this.
-
Dmitry Timoshkov -
Jesse Allen -
Stefan Dösinger