imgui

C++23 module package for Dear ImGui on mcpp.

This package uses compat.imgui for upstream Dear ImGui sources and provides module interfaces for the core API plus GLFW/OpenGL3 backend entry points.

Modules

• imgui.core
  • Core Dear ImGui context, frame, widget, and draw-data APIs.
• imgui.backend.glfw
  • GLFW platform backend plus a small GLFW window/context helper surface.
• imgui.backend.opengl3
  • OpenGL3 renderer backend.
• imgui.backend.glfw_opengl3
  • Convenience module that re-exports core, GLFW, and OpenGL3 backend modules and provides combined lifecycle helpers.

Dependencies

The root package depends on:

• compat.imgui = "1.92.8"
• compat.glfw = "3.4"
• compat.opengl = "2026.05.31"

The repository does not vendor Dear ImGui sources. Source and header files come from compat packages through mcpp dependency metadata.

Quick Start

mcpp build
mcpp test
cd examples/basic
mcpp run

Expected headless example output:

Dear ImGui 1.92.8 module frame ok

Backend Example

The minimal GLFW/OpenGL3 window example uses the combined backend module and does not use #include in consumer code:

cd examples/minimal_window
mcpp build
mcpp run

It requires an OpenGL runtime that is visible to the mcpp/xlings runtime. If GLFW cannot create the window, the example prints the GLFW error text. The compat.opengl package supplies OpenGL registry/header content; it does not bundle a platform libGL/GLX runtime.

The larger GLFW/OpenGL3 example builds on CI but should be run only in an environment with a working display and OpenGL context:

cd examples/glfw_opengl3
mcpp build
mcpp run

Consumer Usage

[dependencies]
imgui = "0.0.1"

Then import the modules you need:

import imgui.core;
import imgui.backend.glfw_opengl3;

int main() {
    ImGuiContext* context = ImGui::CreateContext();
    ImGui::SetCurrentContext(context);
    ImGui::DestroyContext(context);
}

Module Surface

src/core.cppm wraps imgui.h through a global module fragment and exports a tested core API surface:

• Types: ImGuiContext, ImFontAtlas, ImGuiIO, ImDrawData, ImVec2.
• Functions: context lifecycle, GetIO, NewFrame, Begin, Button, TextUnformatted, End, Render, and GetDrawData.

Backend modules adapt the official Dear ImGui backend headers internally and export explicit wrapper functions. Consumer code should only need module imports for the surfaces exposed by this package.

Verification

The 0.0.1 release state is verified with mcpp 0.0.44:

• mcpp build
• mcpp test
• cd examples/basic && mcpp run
• cd examples/minimal_window && mcpp build
• cd examples/glfw_opengl3 && mcpp build

License

The wrapper code in this repository is MIT licensed. Dear ImGui is MIT licensed and provided by the compat.imgui package.