gdi

My pure DotNET library runs as a plugin inside an unmanaged desktop application. I've been getting a steady (though low) stream of crash reports that seem to indicate a problem with GDI handles (fonts in error messages etc. revert to the system font, display of all sorts of controls break down, massive crash shortly after). My Forms have few controls, but I do a lot of GDI+ drawing in User controls. What's a good way to tell how many handles I'm using, or even leaking? Thanks, David I've had to deal with the same kind of problem in the past. In order to inspect how many GDI objects your

I'm debugging a potential GDI Handle Leak. Thanks to @Alois Kraus , there is a WinDbg script which performs a handle count. From my debugging sessions, especially for .NET , I find that usually, it's better to have 32-bit dumps of 32-bit processes and 64-bit dumps of 64-bit processes. Unfortunately, with 2 crash dumps I received, the script does not work. Looking deeper into it, I found out that the GdiSharedHandleTable is null in those dumps: 0:000> dt ntdll!_PEB GdiSharedHandleTable @$peb +0x094 GdiSharedHandleTable : (null) Now, on his website , Alois mentions Important: If you are running

To sketch the background of this question : at work we use Dell Precision workstations. My current one has got an NVidia Quadro FX1700. My team is developing the graphics components for a real time data acquisition system. So we are always looking out to see if the graphics operations don't use up too much CPU time. For quick checks, we have a couple of test programs that we run, which draw scenes at a specified rate ( e.g. 10 fps ) and we use plain old Task Manager to see where CPU usage is at. One of these programs is heavy on GDI DrawRectangle calls ( which are filled ). This program always

Whenever I install a new font on a Windows 2003 server, I can't use it immediately in my asp.net web application. The application gets the font through the CreateFontIndirect gdi32.dll win api, and then use this font to create a dynamic text image in my asp.net application. It seems like fonts get cached somewhere, because I will just get the default font returned. The font cache gets updated after a reboot, and then I get the correct font, but obviously I wouldn't like to do a reboot on a production server just for getting a new font to work. Is there a way to flush the font cache? By default

Summary Using Windows GDI to convert 24-bit color to indexed color, it seems GDI chooses colors which are "close enough" even though there are exact matches in the supplied palette. Can anyone confirm this as a GDI issue or am I making a mistake somewhere? Maybe there's a "please check the whole palette for color matches" flag which I've failed to find? Note: This is not about quantizing. The source is 24-bit but contains 256 or fewer colors so an exact palette is trivial to calculate. The problem is GDI doesn't use the full palette. Workaround I've worked around the problem by mapping the