Why is imgui installation not intuitive?

[FreePhoenix888]

Conan center shows you only this command to install imgui:

[requires]
imgui/cci.20230105+1.89.2.docking

And this command to find and link it to your app in cmake:

# ...
find_package(imgui REQUIRED)
# ...
target_link_libraries(YOUR_TARGET imgui::imgui)

But in this repo we see that we need two other libs:

examples/libraries/dear-imgui/basic/conanfile.txt

Lines 3 to 4 in 3244d6a

	glfw/3.3.6
	glew/2.2.0

Bindings:

examples/libraries/dear-imgui/basic/conanfile.txt

Lines 12 to 16 in 3244d6a

	[imports]
	./res/bindings, imgui_impl_glfw.cpp -> ../bindings
	./res/bindings, imgui_impl_opengl3.cpp -> ../bindings
	./res/bindings, imgui_impl_glfw.h -> ../bindings
	./res/bindings, imgui_impl_opengl3.h -> ../bindings

Options:

examples/libraries/dear-imgui/basic/conanfile.txt

Lines 9 to 10 in 3244d6a

	[options]
	glew:shared=False

Another generator(that is not showed in conan center instruction):

examples/libraries/dear-imgui/basic/conanfile.txt

Lines 6 to 7 in 3244d6a

	[generators]
	cmake_find_package_multi

Use config keyword for find_package:

examples/libraries/dear-imgui/basic/CMakeLists.txt

Lines 7 to 10 in 3244d6a

	# CONFIG option is important so that CMake doesnt search for modules into the default modules directory
	find_package(imgui CONFIG)
	find_package(glfw3 CONFIG)
	find_package(glew CONFIG)

And a lot of other things you can see here:
https://github.com/conan-io/examples/blob/master/libraries/dear-imgui/basic/CMakeLists.txt#L7-L10

[jcar87]

Hi @FreePhoenix888 - thank you for your feedback.

Please keep in mind that this repository (examples) is for Conan 1.x. Conan 2.0 was released about a year ago, and we have a new repository for examples: https://github.com/conan-io/examples2, following the tutorials you can find at: https://docs.conan.io/2/tutorial.html

As for imgui, it's a special library - the complexities stem from the source code of imgui itself:
https://github.com/ocornut/imgui/wiki/Getting-Started#compilinglinking

imgui can be powered by different backends (e.g OpenGL, DirectX, etc) - but some of the public function calls you would make to imgui also require you to make OS-specific calls - so it's not a fully encapsulated abstraction, which has some implications in how this is handled, and requires the consumer to also specify which backend to use (that's why you see calls to find package for glfw and glew, while there are other alternatives). So in short, it's not very intuitive because the library itself follows a different pattern than most others. However, it is still a hugely popular library and the example was written with the ability of being cross-platform and compatible with most mainstream OSs.

[FreePhoenix888]

As for imgui, it's a special library - the complexities stem from the source code of imgui itself: https://github.com/ocornut/imgui/wiki/Getting-Started#compilinglinking

imgui can be powered by different backends (e.g OpenGL, DirectX, etc) - but some of the public function calls you would make to imgui also require you to make OS-specific calls - so it's not a fully encapsulated abstraction, which has some implications in how this is handled, and requires the consumer to also specify which backend to use (that's why you see calls to find package for glfw and glew, while there are other alternatives). So in short, it's not very intuitive because the library itself follows a different pattern than most others. However, it is still a hugely popular library and the example was written with the ability of being cross-platform and compatible with most mainstream OSs.

To make it clear for a new user we should have something like readme in npm for author to be able tell users about such things that should be done by used to setup a recipe.