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I've got a .dll project in which I'm utilizing Direct 2D to draw on a window. For some reason, one line is continually giving me errors when I attempt to run it:
// Create a Direct2D factory.
hr = D2D1CreateFactory(D2D1_FACTORY_TYPE_SINGLE_THREADED, &m_pDirect2dFactory);
The problem is that this line works fine when I run the project as a .exe. I copied and pasted the whole page over from the working project to the new .dll but it now gives me this error:
Severity Code Description Project File Line Suppression State Details Error LNK2019 unresolved external symbol D2D1CreateFactory referenced in function "long __cdecl D2D1CreateFactory(enum D2D1_FACTORY_TYPE,struct _GUID const &,void * *)" (?D2D1CreateFactory@@YAJW4D2D1_FACTORY_TYPE@@AEBU_GUID@@PEAPEAX@Z) DxfDrawer C:\Users\REDACTED\source\repos\Direct2DinWPF\DxfDrawer\DxfDrawer.obj 1
Here is a link to my project. The line in question is line 126.
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Is your DLL project linking with D2d1.lib?
As far as I can tell it is. It shows up under my external dependencies and everything else works if I comment out the CreateFactory call
As far as im aware it is. It shows up in my external dependencies and it doesnt give me any issues with the usings
I suggest you repost a working link to your project so the details can be seen.
Apologies, link fixed.
For some reason the linker was not searching d2d1.lib which caused the LNK2019 error. If you add d2d1.lib to the linker inputs in the project property page instead of using the pragma directive it will build successfully.
I also noticed that if you position the pragma directives for the libraries after the headers then the build will succeed.
Perfect. Thanks.
@Forrest Crawford You're welcome. The reason that the linker was not searching d2d1.lib was because when the pragma directives were placed at the top of the file the generated object module did not contain the directive to link the library. You can see this for yourself -- in a developer command prompt run dumpbin /directives dxfdrawer.obj. Then run it again after putting the pragmas after the headers. The directive will then be present in the .obj file.
I don't know if this is a VS bug or not but you might consider reporting it.
@Forrest Crawford
Yes, please submit a bug report on this; this is behaviour I wasn't expecting, and (by good fortune of always adding the lib comment after the header include) have never experienced before.
If you post a link to the bug report back here we can comment on it and vote for it.