Backends

ImGui is a very embeddable library because it abstracts things like drawing to the screen and creating windows to its backends. There are many official backends, but currently CImGui.jl only supports the GLFW/OpenGL3 backend.

CImGui.set_backend — Function
set_backend(backend::Symbol)

Set the backend to use. Currently supported backends are:

  • :GlfwOpenGL3 (GLFW/OpenGL3, requires ModernGL.jl and GLFW.jl)
CImGui.render — Function
render(ui::Function, ctx::Ptr{lib.ImGuiContext}; kwargs...)

Top-level function to call a renderloop implemented by the backend selected by set_backend(). This function will not return until the program exits, either by the user closing the window or ui() returning :imgui_exit_loop. It will also not yield the loop, though you may explicitly call yield() in ui().

Arguments

Positional arguments:

  • ui: The function to execute in the renderloop. This where all the GUI code with calls to CImGui should go.
  • ctx: The ImGui context to use. Note that DestroyContext() will automatically be called on it at the end of the renderloop, so it will be unusable afterwards.

Keyword arguments:

  • hotloading=true: Enable calling the latest version of ui() using @invokelatest. This is handy when using Revise.jl.
  • on_exit::Union{Function, Nothing}=nothing: A destructor/finalizer function that will be called before destroying ctx. This might be useful if you're using some external library that needs to be cleaned up in a certain order.
  • clear_color=Cfloat[0.45, 0.55, 0.60, 1.00]: The color of the window background. This can also be a Ref{Vector{Cfloat}} if you want to control the color dynamically (see the official demo for an example).
  • window_size=(1280, 720): The initial size of the window.
  • window_title="CImGui": The window title.
  • engine=nothing: An optional ImGuiTestEngine.Engine instance. If there are any tests registered with the test engine they will be queued and run automatically.
  • opengl_version::VersionNumber=v"3.2": The OpenGL version to use.