failure to compile imgui, glfw, opengl on linux with gcc 11.2

I've recently started coding with c++ and the project that im currently on requires imgui. so i set up the .h and .cpp libraries in a folder called "include" in the same folder as the source code. I'm currently trying to run the cpp in https://github.com/ocornut/imgui/tree/master/examples/example_glfw_opengl3 and compile it with gcc using gcc imgui.cpp -lstdc++ -lglfw -lGL -limgui but i just get

/usr/bin/ld: cannot find -limgui
collect2: error: ld returned 1 exit status

yes i know there is a make file in the link but im using the file in another folder.

Solution

Assuming you downloaded imgui to a place called $IMGUI_DIR and the file that contains your main function is main.cpp, your compile commandline should look like the following: (the \ are just there to break up the command)

g++ main.cpp -o main \
$IMGUI_DIR/imgui*.cpp $IMGUI_DIR/backends/imgui_impl_glfw.cpp $IMGUI_DIR/backends/imgui_impl_opengl3.cpp \
-I $IMGUI_DIR -I $IMGUI_DIR/backends \
-lglfw -lGL

In order, you tell the compiler:

Where your code is and where to put the output
What Imgui code to include, namely the core library and the two backends you want to use
Where Imgui code should look for its headers

If all this sounds like a lot, know that you can simply build the example you linked and override IMGUI_DIR at compile time with make IMGUI_DIR=/path/to/imgui