Dear ImGui is described as 'Bloat-free graphical user interface library for C++. It outputs optimized vertex buffers that you can render anytime in your 3D-pipeline enabled application. It is fast, portable, renderer agnostic and self-contained (no external dependencies)' and is an app in the development category. There are more than 10 alternatives to Dear ImGui for a variety of platforms, including Mac, Windows, Linux, Self-Hosted and BSD apps. The best Dear ImGui alternative is Qt, which is both free and Open Source. Other great apps like Dear ImGui are GTK, wxWidgets, Slint and Iced.
Qt is a cross-platform application framework that is widely used for developing application software that can be run on various software and hardware platforms with little or no change in the underlying codebase, while having the power and speed of native applications.
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GTK is a multi-platform toolkit for creating graphical user interfaces. Offering a complete set of widgets, GTK is suitable for projects ranging from small one-off tools to complete application suites.
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wxWidgets is a C++ library that lets developers create applications for Windows, OS X, Linux and UNIX on 32-bit and 64-bit architectures as well as several mobile platforms including Windows Mobile, iPhone SDK and embedded GTK+.
GUI toolkit for Rust, C++, and JavaScript to efficiently develop fluid graphical user interfaces for embedded devices and desktop applications.
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The tkinter package (“Tk interface”) is the standard Python interface to the Tcl/Tk GUI toolkit. Both Tk and tkinter are available on most Unix platforms, including macOS, as well as on Windows systems.
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The Fast, Light Toolkit (FLTK, pronounced fulltick) is a cross-platform graphical user interface (GUI) library developed by Bill Spitzak and others. Made to accommodate 3D graphics programming, it has an interface to OpenGL, but it is also suitable for general GUI programming.
Nevron Open Vision for .NET is a suite of advanced UI components that helps you develop feature-rich Web (Blazor WebAssenbly) and Desktop (WinForms, WPF, Xamarin.Mac) applications from a single code base.
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Repose is a Rust UI framework with a Compose-like programming model. It's organized as a small core (repose-core) plus higher-level UI/layout (repose-ui) and platform runners (repose-platform) that currently target desktop (winit) and Android, with web support.
Gio is a library for writing cross-platform immediate mode GUI-s in Go. Gio supports all the major platforms: Linux, macOS, Windows, Android, iOS, FreeBSD, OpenBSD and WebAssembly.
