How do you compile ImGui on Windows vscode MinGW? - c++

Question

Right, so I have been trying for weeks now to get ImGui to work with my windows OpenGL project. I have tried everything. So, can someone please show me how to compile ImGui with the rest of my project. Like how to add it to the vs code task file or how to add it to my makefile. Also when I have asked before people have said use CMake. But I can't because CMake doesn't work so I can't use it and I don't want to waste more time to try and get it to work. So, anyone who knows how to help please do.
Here is my makefile:
CXX = g++
Flags = -std=c++17 -Wall -Wformat
Libs = -lGL -lGLEW -lglfw -ldl
OBJDIR = obj
VSXFLAGS = src/vendor/imgui/imgui_impl_glfw.h src/vendor/imgui/imgui_impl_opengl3.h
Filez = src/Rendering/*.cpp src/Rendering/*.h src/Core/*.h src/Core/*.cpp src/vendor/glm/gtc/type_ptr.hpp
Includes = -Isrc/PCH/ -Isrc/ -Iinclude/ -Isrc/Rendering/Buffers/ -Isrc/Core/ -Isrc/Rendering/ -Isrc/vendor/imgui -Isrc/FileManagement/ -Ires/ -Isrc/vendor/glm/ -Isrc/vendor/stb_image -Isrc/vendor/
all: main.cpp
$(CXX) $(Flags) $(Includes) $(Filez) main.cpp lib/imgui.a lib/Buffers.a -o main $(Libs)
clean:
rm $(OBJDIR)/*.o *.o
This is my file structure:
[]2

Answer 1

As ImGui is a separate library your project should link against it rather than compiling it with the rest of your project each time.
Here's how I build the library (both static and shared) in MSYS2 shell:
# change the next value to where you want to install it
export INSTALLPREFIX=/D/Prog/3rdparty
# fix DLL exports in imgui.h
mv imgui.h imgui.h.bak
cat > imgui.h << EOF
#if !defined(IMGUI_API) && defined(_WIN32)
#if defined(BUILD_IMGUI_SHARED)
#define IMGUI_API __declspec(dllexport)
#elif !defined(STATIC) && !defined(STATIC_IMGUI)
#define IMGUI_API __declspec(dllimport)
#else
#define IMGUI_API
#endif
#endif
EOF
sed -e "s/static char\s*EmptyString/IMGUI_API &/" imgui.h.bak >> imgui.h
# don't export inline functions in imgui_internal.h (version >= 1.81)
sed -i.bak -e "s/IMGUI_API \(~*ImGuiTable()\)/\1/" imgui_internal.h
~/buildstatus.sh build &&
touch SUCCESS &&
for F in *.cpp; do
echo CXX $F &&
g++ -O3 -I. $F -c -o $F.o -DBUILD_IMGUI_SHARED || rm -f SUCCESS
done &&
ls -1 SUCCESS > /dev/null &&
ar cru libimgui.a *.cpp.o &&
( echo EXPORTS; nm -f posix --defined-only -p libimgui.a | sed -n -e "s/^\([^ ]*\) T .*$/\1/p" | sed -e "s/^__*/_/" | grep "Im" ) > imgui.def &&
g++ -shared -s -mwindows -def imgui.def -o imgui.dll libimgui.a -Wl,--out-implib,libimgui.dll.a -Wl,--as-needed -limm32 &&
~/buildstatus.sh install &&
mkdir -p $INSTALLPREFIX/include/imgui $INSTALLPREFIX/lib $INSTALLPREFIX/bin &&
cp -f *.cpp *.h $INSTALLPREFIX/include/imgui/ &&
cp -f *.a $INSTALLPREFIX/lib/ &&
cp -f *.dll $INSTALLPREFIX/bin/ &&
echo SUCCESS
Make sure your MSYS2 environment points to the same compiler as VSCode in case its different (add to PATH).
My build was done with a recent standalone GCC/MinGW-w64 from https://winlibs.com/