DX11 Windows crash when some features are unsupported.

[Nemirtingas]

Version/Branch of Dear ImGui:

Version: Any
Branch: master

Back-end/Renderer/Compiler/OS

Back-ends: imgui_impl_dx11.cpp + imgui_impl_win32.cpp
Compiler: MSVC (VS Community 2019), C++14
Operating System: Windows 10

My Issue/Question:
When using my game overlay, some DX11 games crash when using the DX11 renderer at

imgui/backends/imgui_impl_dx11.cpp

Line 267 in d6a5cc7

ctx->PSSetSamplers(0, 1, &old.PSSampler); if (old.PSSampler) old.PSSampler->Release();

because

imgui/backends/imgui_impl_dx11.cpp

Line 209 in d6a5cc7

ctx->PSGetSamplers(0, 1, &old.PSSampler);

failed silently (this function has no return code) and the content of old.PSSampler will then be uninitialized (some random stuff in it).

My quick fix is just to initialize old like so:

BACKUP_DX11_STATE old = {};

All pointers will be nulled and not used because there are already if(old.thing != NULL) checks in the code.

Its an old issue I fixed on my project, I'll see if I can remember on what game it crashed.

[ocornut]

That makes sense. Merged the fix: 858ea17
Thanks a lot!

[Nemirtingas]

Thanks