RTXUI

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Getting Started ​

This page covers what you need to build RTXUI, how to add it to a CMake project, and how to build the repository itself.

Requirements ​

  • A C++23 compiler. C++23 is required to build and use RTXUI. If available, C++26 enables reflection, which avoids having to bind C++ members manually.
  • Linux or macOS. The terminal backend requires POSIX termios and SIGWINCH. Windows is not supported (no ConPTY backend); CMake terminates configuration on Windows platforms with an explicit error. RTXUI also targets the browser through Emscripten / WebAssembly.
  • CMake 3.24 or newer.
  • Ninja (optional, faster builds than Make).

On Debian or Ubuntu:

bash
sudo apt install cmake ninja-build g++-14

Select the compiler per build rather than changing system defaults — pass it to CMake explicitly:

bash
CC=gcc-14 CXX=g++-14 cmake -B build -G Ninja

(For Clang, install it from your distribution or apt.llvm.org and set CC=clang CXX=clang++ the same way.)

Adding RTXUI to your project ​

With FetchContent ​

The simplest integration downloads RTXUI at configure time:

cmake
cmake_minimum_required(VERSION 3.24)
project(my_app LANGUAGES CXX)

set(CMAKE_CXX_STANDARD 23)  # Use 26 to enable automatic static reflection.
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_EXTENSIONS OFF)

include(FetchContent)
FetchContent_Declare(
  rtxui
  GIT_REPOSITORY https://github.com/ArthurSonzogni/RTXUI.git
  GIT_TAG        main  # Pin a tag or commit for reproducible builds.
)
FetchContent_MakeAvailable(rtxui)

add_executable(my_app main.cpp)
target_link_libraries(my_app PRIVATE rtxui)

Link against the rtxui target, not rtxui_lib. Built-in elements register themselves through static initializers, and the rtxui target carries the linker flags that keep those initializers from being discarded. Linking rtxui_lib directly can produce binaries where tags like <button> silently fail to resolve.

With an installed package ​

If RTXUI has been installed (cmake --install), consume it with find_package:

cmake
find_package(rtxui REQUIRED)
target_link_libraries(my_app PRIVATE rtxui::rtxui)

First program ​

Create main.cpp:

cpp
#include <rtxui/rtxui.hpp>

class App : public rtxui::Component<App> {
 public:
  std::string_view view = R"html(
    <div>Hello from RTXUI.</div>
  )html";
};

int main() {
  auto app = rtxui::Ref<App>::New();
  rtxui::Screen screen(app);
  screen.Loop();
}

Configure, build, and run:

bash
CC=gcc-14 CXX=g++-14 cmake -B build -G Ninja -DCMAKE_BUILD_TYPE=Release
cmake --build build
./build/my_app

Press Ctrl-C to quit. The Hello World walkthrough explains each line and adds styling.

Building the repository ​

To work on RTXUI itself, or to run its examples and tests:

bash
git clone https://github.com/ArthurSonzogni/RTXUI.git
cd RTXUI
cmake -B build -G Ninja -DCMAKE_BUILD_TYPE=Release \
      -DRTXUI_BUILD_TESTS=ON -DRTXUI_BUILD_EXAMPLES=ON
cmake --build build
  • Run the test suite: ./build/rtxui_test (or ctest --test-dir build)
  • Run an example: ./build/rtxui_example_demo
  • Sanitizer build: add -DRTXUI_SANITIZE=ON for AddressSanitizer and UndefinedBehaviorSanitizer.

The examples under example/ are the fastest way to explore what the engine can do; each one is a single self-contained file.