Early development · .NET 10

Build native C# apps with ImGui.

ImApp is a lightweight application framework that gives your C# application a native window, OpenGL rendering, and Dear ImGui — without adding another UI layer.

Get Started Read Documentation

Program.cs C#

using Hexa.NET.ImGui;
using ImApp;

using var app = new App(new WindowOptions
{
    Title = "My Application",
    Width = 1000,
    Height = 700
});

app.Run(() =>
{
    ImGui.Begin("Hello");

    ImGui.Text("Hello from ImApp!");

    if (ImGui.Button("Click me"))
        Console.WriteLine("Clicked!");

    ImGui.End();
});

Features

A small layer around a powerful UI library.

ImApp handles the application lifecycle, window, rendering and timing while Dear ImGui remains the UI API.

Native Windows

Desktop windows powered by GLFW with configurable window behavior.

Dear ImGui

Use the Dear ImGui API directly without another widget abstraction.

OpenGL

Built-in OpenGL rendering through the ImGui OpenGL backend.

□

Window Control

Borderless, transparent, resizable, maximized, topmost and passthrough windows.

⊞

Docking

Enable Dear ImGui docking for IDE-style application interfaces.

FPS

Frame Limiting

Configure a target rendering rate or disable the limiter completely.

Documentation

Everything you need to get started.

A compact reference for the core ImApp API.

Quick Start

Create an App, configure its window and pass your UI to Run.

using Hexa.NET.ImGui;
using ImApp;

using var app = new App(new WindowOptions
{
    Title = "My Application",
    Width = 1000,
    Height = 700
});

app.Run(() =>
{
    ImGui.Begin("Hello");
    ImGui.Text("Hello from ImApp!");
    ImGui.End();
});

Window Options

WindowOptions controls how the native GLFW window is created.

var options = new WindowOptions
{
    Title = "My Application",
    Width = 1000,
    Height = 700,

    Decorated = true,
    Resizable = true,
    Transparent = false,
    Topmost = false,

    Maximized = false,
    Visible = true,
    Focused = true,

    MousePassthrough = false,
    DockingEnabled = false,
    HostWindow = true,

    TargetFps = 144,
    FontSize = 17
};

Property	Default	Description
Title	"ImApp Window"	Window title
Width	800	Initial width
Height	600	Initial height
Decorated	true	Enable native decorations
Resizable	true	Allow resizing
Transparent	false	Enable transparent framebuffer
Topmost	false	Keep above normal windows
Maximized	false	Start maximized
Visible	true	Show window initially
Focused	true	Request initial focus
MousePassthrough	false	Pass mouse input through
DockingEnabled	false	Enable ImGui docking
HostWindow	true	Create full-window ImGui host
TargetFps	100	Target rendering rate; 0 disables limiter
FontSize	17	Embedded font size

Host Window

By default, ImApp creates a full-window ImGui host and executes your UI inside it.

using var app = new App(new WindowOptions
{
    HostWindow = true
});

app.Run(() =>
{
    ImGui.Text("Hello from ImApp!");
});

Set HostWindow = false when you want to manage the ImGui windows yourself.

using var app = new App(new WindowOptions
{
    HostWindow = false
});

app.Run(() =>
{
    ImGui.ShowDemoWindow();
});

Docking

Enable Dear ImGui docking through DockingEnabled.

using var app = new App(new WindowOptions
{
    Width = 1200,
    Height = 800,
    DockingEnabled = true
});

app.Run(() =>
{
    ImGui.ShowDemoWindow();
});

Transparent & Borderless Windows

Combine transparent rendering with disabled decorations for overlay-style applications.

using var app = new App(new WindowOptions
{
    Decorated = false,
    Transparent = true,
    MousePassthrough = true
});

Font

ImApp includes Noto Sans Regular and loads it automatically. Change its size with FontSize.

using var app = new App(new WindowOptions
{
    FontSize = 18
});

Dependencies

ImApp provides the application, window, rendering, timing and lifecycle layer on top of these components.

.NET 10 Dear ImGui Hexa.NET.ImGui Hexa.NET.GLFW Hexa.NET.OpenGL ImGui GLFW Backend ImGui OpenGL3 Backend HexaGen.Runtime

Installation

Install and start building.

ImApp is available as a NuGet package.

.NET CLI

dotnet add package ImApp

PackageReference

<PackageReference
    Include="ImApp"
    Version="0.2.0" />

Built with

Small by design.

ImApp does not replace your UI toolkit. It provides the application layer around it.

.NET 10 Dear ImGui Hexa.NET.ImGui GLFW OpenGL Noto Sans