Key Features

Works everywhere¶

• Cross-platform in C++ and Python: Works on Windows, Linux, macOS, iOS, Android, and WebAssembly!

• Web ready: Develop full web applications, in C++ via Emscripten; or in Python thanks to ImGui Bundle’s integration within Pyodide.

First class support for Python¶

• Python Bindings: Using Dear ImGui Bundle in Python is extremely easy and productive.

• Well documented Python bindings and stubs: The Python bindings stubs reflect the C++ API and documentation, serving as a reference and aiding autocompletion in your IDE. See for example the stubs for imgui, and for hello_imgui.

• Use it to create standalone apps (on Windows, macOS, and Linux), or to add interactive UIs to your notebooks. Deploy your apps on the web with ease, using Pyodide.

Easy to use & well documented¶

• The Immediate Mode GUI (IMGUI) paradigm is simple and powerful, letting you focus on the creative aspects of your projects.

• Easy to use, yet very powerful: Start your first app in 3 lines.

• Interactive Demos and Documentation: Quickly get started with our interactive manual and demos that showcase the capabilities of the pack. Read or copy-paste the source code (Python and C++) directly from the interactive manual!

Always up-to-date¶

• Auto-generated bindings: Python bindings are automatically generated, ensuring they stay synchronized with C++ APIs.

• Version tracking: ImGui Bundle version numbers match Dear ImGui releases (e.g., ImGui Bundle 1.91.x includes Dear ImGui 1.91.x). Updates typically follow within days of upstream releases.

High performance¶

• Fast: Rendering is done via OpenGL (or any other renderer you choose), through native code.

Comprehensive Library Integration¶

Dear ImGui Bundle isn’t just ImGui - it’s a curated ecosystem with more than 20 integrated libraries, where Each library is:

• Available in Python and C++ with consistent APIs

• Always up to date, since Python bindings are autogenerated

• Documented with interactive examples

Core Libraries¶

• Dear ImGui : Bloat-free Graphical User interface with minimal dependencies

• ImGui Test Engine : Dear ImGui Tests & Automation Engine

• Hello ImGui : cross-platform Gui apps with the simplicity of a “Hello World” app

Plotting & Visualization¶

• ImPlot : Immediate Mode Plotting

• ImPlot3D : Immediate Mode 3D Plotting

• ImmVision : Immediate image debugger and insights

• imgui_tex_inspect : A texture inspector tool for Dear ImGui

Text Editing & Markdown¶

• ImGuiColorTextEdit : Colorizing text editor for ImGui

• imgui_md : Markdown renderer for Dear ImGui using MD4C parser

Tools¶

• ImGuizmo : Immediate mode 3D gizmo for scene editing

• imgui-node-editor : Node Editor built using Dear ImGui

• NanoVG : Antialiased 2D vector drawing library on top of OpenGL

Widgets¶

• ImFileDialog : A file dialog library for Dear ImGui

• portable-file-dialogs : OS native file dialogs library (C++11, single-header)

• imgui-knobs : Knobs widgets for ImGui

• imspinner : Set of nice spinners for imgui

• imgui_toggle : A toggle switch widget for Dear ImGui

• ImCoolBar : A Cool bar for Dear ImGui

• imgui-command-palette : A Sublime Text or VSCode style command palette in ImGui

Common Questions¶

Is It Interesting for Developers?¶

Absolutely yes, for several reasons:

1. Joy of Use¶

The immediate-mode paradigm is genuinely refreshing:

# Your code directly expresses intent
if imgui.button("Click Me"):
    do_something()

This is more readable and maintainable than callback spaghetti or complex widget trees.

2. Rapid Development¶

From zero to functional UI is remarkably fast:

• No UI designer needed

• No XML/JSON layouts to maintain

• Changes appear immediately

• Easy to iterate

3. Power When You Need It¶

The framework scales from simple to complex:

• Start with a simple window and buttons

• Add docking and multiple windows

• Incorporate 3D visualization

• Build node-based editors

• Create custom widgets

All while maintaining code clarity.

4. Cross-Platform Reality¶

The cross-platform support actually works:

• Same code runs on Windows, macOS, Linux

• WebAssembly with Python runtime (!!)

• No platform-specific hacks needed

• Mobile support (iOS, Android) is real (in C++)

5. Active Community¶

• Dear ImGui itself has 60k+ stars and is used in AAA games

• Dear ImGui Bundle is based on Dear ImGui and adds comprehensive Python support

• 1k+ stars

• Regular updates and maintenance, keeping up with Dear ImGui upstream

“Isn’t rebuilding the UI every frame slow?”¶

No! Because:

• Widget calls are cheap (just generate drawing commands)

• Actual rendering is GPU-accelerated

• Typical frame times: < 1ms for most UIs

• Easily achieves 60+ FPS even with complex interfaces

“How’s the Python performance?”¶

Excellent! Because:

• Each widget call crosses to C++ once per frame

• Heavy lifting (rendering) is in C++

• Python overhead is < 0.5ms per frame typically

• Real bottleneck is usually your application logic, not the GUI

“Does it work on the web?”¶

Yes, impressively!

• C++ → Emscripten → WebAssembly

• Python → Pyodide → WebAssembly (!!)

• Full Python runtime in browser

• Native-speed rendering via WebGL

• Check the interactive manual: traineq.org/ImGuiBundle

Comparison with Alternatives¶

The examples below implement the same “fruit picker” app.

Compare the code styles:

from imgui_bundle import imgui, hello_imgui

selected_idx = 0
items = ["Apple", "Banana", "Cherry"]

def gui():
    global selected_idx
    imgui.text("Choose a fruit:")
    _changed, selected_idx = imgui.list_box("##fruits", selected_idx, items)
    imgui.text(f"You selected: {items[selected_idx]}")

hello_imgui.run(gui, window_title="Fruit Picker")

from PyQt6.QtWidgets import QApplication, QWidget, QVBoxLayout, QLabel, QListWidget

items = ["Apple", "Banana", "Cherry"]

class FruitPicker(QWidget):
    def __init__(self):
        super().__init__()
        layout = QVBoxLayout()
        self.label = QLabel("Choose a fruit:")
        self.list_widget = QListWidget()
        self.list_widget.addItems(items)
        self.result_label = QLabel(f"You selected: {items[0]}")
        self.list_widget.currentRowChanged.connect(self.on_selection_changed)
        layout.addWidget(self.label)
        layout.addWidget(self.list_widget)
        layout.addWidget(self.result_label)
        self.setLayout(layout)

    def on_selection_changed(self, index):
        self.result_label.setText(f"You selected: {items[index]}")

app = QApplication([])
window = FruitPicker()
window.show()
app.exec()

import dearpygui.dearpygui as dpg

items = ["Apple", "Banana", "Cherry"]
dpg.create_context()

def on_selection_changed(sender, app_data):
    dpg.set_value("result_label", f"You selected: {app_data}")

with dpg.window(tag="Primary Window", label="Fruit Picker"):
    dpg.add_text("Choose a fruit:")
    dpg.add_listbox(items=items, callback=on_selection_changed, num_items=len(items))
    dpg.add_text("You selected: ", tag="result_label")

dpg.create_viewport(title='Fruit Picker', width=400, height=300)
dpg.setup_dearpygui()
dpg.show_viewport()
dpg.set_primary_window("Primary Window", True)
dpg.start_dearpygui()
dpg.destroy_context()

from nicegui import ui

selected_idx = -1
items = ["Apple", "Banana", "Cherry"]

def on_selection_change(e):
    global selected_idx
    selected_idx = items.index(e.value)
    selection_label.text = f"You selected: {e.value}"

ui.label("Choose a fruit:")
dropdown = ui.select(options=items, value=items[0], on_change=on_selection_change)
selection_label = ui.label(f"You selected: {items[0]}")

ui.run(title="Fruit Picker")

import gradio as gr

items = ["Apple", "Banana", "Cherry"]
selected_item = items[0]

def on_selection_change(choice):
    global selected_item
    selected_item = choice
    return f"You selected: {choice}"

with gr.Blocks() as demo:
    gr.Markdown("# Fruit Picker")
    gr.Markdown("Choose a fruit:")
    dropdown = gr.Dropdown(choices=items, value=items[0], label="Choose a fruit")
    output = gr.Textbox(value=f"You selected: {items[0]}", label="Selection", interactive=False)
    dropdown.change(fn=on_selection_change, inputs=dropdown, outputs=output)

demo.launch()