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Dear ImGUI extension for Defold

This project adds support for Dear ImGUI in Defold. Dear ImGUI is described as a "Bloat-free Graphical User interface for C++ with minimal dependencies". It is perfect for quickly creating a debug interface or for creation of in-game tools and settings.

imgui1 imgui2

Why no auto-generated bindings?

Projects such as cimgui offers Dear ImGUI bindings for a number of different languages, including Lua. It could be used to generate the bindings for this extension, BUT I'm doing this as a way to learn more about the Dear ImGUI API and as such it makes more sense for me to write the bindings by hand.

IMPORTANT

  • The project currently only has bindings for a small subset of the Dear ImGUI API.
    • More bindings are added as I need them. Pull requests are accepted!

Platforms support

The current state of platform support:

  • ✅ macOS
  • ✅ Linux
  • ✅ Windows
  • ✅ Android
  • ✅ iOS
  • ✅ HTML5

Usage

Refer to example/example.script to learn how to use the extension. Also check the bindings in LuaInit() in extension_imgui.cpp.

Input

You need to update the input state in Dear ImGUI each frame to accurately reflect user input:

  • imgui.set_key_down(key, pressed) - Set the pressed state of a key. The key must be one of the imgui.KEY_ constants
  • imgui.set_key_modifier_super(pressed)
  • imgui.set_key_modifier_alt(pressed)
  • imgui.set_key_modifier_ctrl(pressed)
  • imgui.set_key_modifier_shift(pressed)
  • imgui.add_input_character(text) - Add keyboard input
  • imgui.set_mouse_input(x, y, left, right, middle, wheel) - Set mouse state (position, buttons and wheel)

You can add the imgui/imgui.script to a game object and let that handle input for you (also make sure to use imgui/bindings/imgui.input_bindings).

Display size

You need to let Dear ImGUI know of any changes to the window size by calling imgui.set_display_size(w, h) when the screen size changes.