Article: Q85596
Product(s): Microsoft Windows Software Development Kit
Version(s): WINDOWS:3.1
Operating System(s):
Keyword(s):
Last Modified: 06-NOV-1999
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The information in this article applies to:
- Microsoft Windows Software Development Kit (SDK) 3.1
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SYMPTOMS
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When the VGAPAL video driver is installed on a system, once an application calls
the SETCOLORTABLE escape to change an entry in the color table associated with a
device context, Windows does not create any dithered brushes for that device
context. Instead, Windows returns the solid brush that most closely matches the
requested color.
RESOLUTION
==========
To work around this problem, reset the color table to its original state by
specifying NULL as the value of the lpInData and lpOutData parameters in a call
to the SETCOLORTABLE escape, as follows:
Escape(hDC, SETCOLORTABLE, 0, NULL, NULL)
STATUS
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Microsoft has confirmed this to be a bug in Windows version 3.1. We are
researching this problem and will post new information here in the Microsoft
Knowledge Base as it becomes available.
MORE INFORMATION
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The SETCOLORTABLE escape is documented on pages 500 and 501 of the "Microsoft
Software Development Kit: Programmer's Reference, Volume 3: Messages, Structures
and Macros" manual.
The comments regarding this escape state the following:
- The color-mapping algorithms in the display driver will most likely not work
with a changed palette.
- If the color index pointed to by the lpInData parameter is 0xFFFF, the
calling application performs all color mapping.
- Once an application restores the color table to its original state, an
application can enable the color-mapping algorithms in the display driver.
However, with the VGAPAL driver, calling the SETCOLORTABLE escape with lpInData
pointing to the 0xFFFE value does not restore dithering.
Additional query words: buglist3.10 3.10
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Keywords :
Technology : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK310
Version : WINDOWS:3.1
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