maksw2

1. https://github.com/Source-SDK-Resources/source-2013-imgui get this

2. get imgui source code
   the path must look like this:
   imgui/thirdparty/imgui
imgui/imgui
   2.1 include the vpc in client_base.vpc
   like this:
   $include "$SRCDIR\imgui\imgui\imgui_system.vpc"

3. comment out these lines in imconfig_source.h: