Debug Your Game in Real-Time with Dear ImGui | .NET Game Development

Andy and Stacey explain how Dear ImGui can speed up debugging for .NET games by building an in-game “debug layer” that shows live state and editor controls while the game is running.

Overview

What problem Dear ImGui solves for game debugging

• Traditional debugging (breakpoints, pausing execution) can be slow and disruptive for games.
• A debug layer lets developers inspect and tweak game state in real time while the game continues running.

What Dear ImGui is (and when to use it)

• Dear ImGui is an immediate mode UI library that’s well-suited for:
  • In-game debug tooling
  • Editor-like controls for designers and developers
  • Rapid iteration on gameplay and simulation parameters
• It’s not intended for player-facing UI (menus/HUD) in most cases.

.NET options: bindings and renderers

The video covers the typical pieces needed to use ImGui in a .NET game:

• .NET bindings
  • ImGui.NET
  • Hexa.NET.ImGui
• A renderer integration for the engine/framework you’re using (example shown with MonoGame).

Building real-time tooling inside the game

Examples of debug-layer capabilities discussed/demonstrated:

• Displaying live game state without stopping execution
• Binding UI controls to game data
• Creating in-game editors
  • Moving sprites
  • Changing shading
  • Pausing simulations
• Using built-in interactivity such as drag-and-drop

Debugging workflow examples

• Using debug layers to reproduce and investigate bugs faster
• Testing edge cases (e.g., walls, movement constraints, AI behavior)
• Adding gameplay debug features (e.g., kill/signal-style debug actions)

Beyond games: other ImGui-style apps

• A brief example of ImGui used outside game development (ImHex hex editor demo).

Links and resources

• Dear ImGui (official repo): https://github.com/ocornut/imgui
• Hexa.NET.ImGui bindings: https://github.com/HexaEngine/Hexa.NET.ImGui
• ImGui.NET bindings: https://github.com/ImGuiNET/ImGui.NET
• MonoGame: https://monogame.net
• Series playlist: https://aka.ms/Quest-to-Compile