Build Unreal Engine menus, HUDs, inventories and in-world UI with HTML, CSS and JavaScript, then change them by clicking on the screen. OrionBrowser renders Chromium-quality interfaces inside UMG, connects them to Blueprints or C++, and ships with WebUIStudio: a desktop studio that previews every screen without starting the game and sends your marked-up changes to Codex or Claude in one click.

Try it before you buy: Playable demo for Windows (Google Drive) · 百度网盘

Documentation · Discord community · Example project

Unreal Engine 5.8 · Windows 64-bit · Blueprint and C++ · full C++ source included

Web-grade motion, effects and 3D

• CSS animations, spring motion, gradients, masks, SVG, Canvas and WebGL 2: anything Chromium 149 draws, made quickly with ordinary web code

• Transparent pages blended over the game, for glass panels and HUDs over a live level

• three.js scenes on a transparent canvas. The sample includes a procedural pavilion with shadows and bloom, a 340,000-star galaxy and a ray-marched black hole

• Effects with full source: holographic foil, lens flare, flowing borders, laser and neon

• Local video with sound (WebM with VP9 and Opus)

• Vue 3, TypeScript and Vite template with live updates while you edit

WebUIStudio: see it, click it, change it

A desktop app that opens from the editor toolbar and runs your real UI source without starting the game.

• Live preview of every page, state and language, from 1280 × 720 to 3440 × 1440

• Inspect any control: id, size, source file and line, matched styles

• A log of every message between the page and Unreal

• Adjust text, color, font, size and spacing live, with a screenshot of your game behind the UI

One-click AI editing with Codex or Claude

• Annotate and send. Mark a control or an area, write what should change, and click Send. A screenshot and the exact source line travel with it.

• New interface from a description. The agent writes and builds the page, and writes the C++ host or lists the Blueprint steps.

• Isolated drafts. The agent works on a copy. Studio runs the type check, tests and build, shows the diff beside a live preview, then applies or undoes it.

• Creation Skill included. A rule set that teaches any coding agent the bridge, lifecycle, controls and build checks.

• AI is optional and uses your own Codex or Claude account. A packaged game never depends on it.

Connected to your game with Blueprint or C++

• Orion WebUI widget for UMG, with a Designer preview

• The page sends events and requests that you accept, reject or defer. Unreal publishes state with revisions that the page acknowledges

• Blueprint only, C++, or both, with more than 190 Blueprint-callable functions

• Native Surface: Render Targets, scene captures and UI materials drawn by Unreal inside the web layout

• Runtime images for avatars and generated icons, and a separate browser widget for remote websites

• Packaged UI runs offline, with no web server

Fonts, localization and sound from Unreal

• Fonts. Bundle web fonts with the page, or serve Unreal Font Face assets through a Font Manifest, with separate body and heading fonts.

• Localization. A Text Catalog sends UI strings through Unreal's localization pipeline, and the page switches language live, without a reload. IME text entry works.

• Sound. Hover and click sounds are played by Unreal from a per-control policy, with no audio code in the page.

CommonUI, gamepad, keyboard and mouse

• Orion WebUI Activatable Widget: push a web screen onto your CommonUI stack with its input mode, back handling and named actions

• Gamepad navigation inside the page: the D-pad or left stick moves focus, accept clicks, back goes back

• Input prompts switch between keyboard hints and gamepad glyphs when the player changes device

WorldUI: interface that follows the world

• Labels, health bars and interaction prompts anchored to Actors and projected onto the screen

• One overlay page per player draws every element, with no browser per Actor

• Distance culling, occlusion checks, screen-edge clamping and distance scaling

• Interactions are checked for visibility and range before your Blueprint decides

Engineered for performance

• InstantScreen. Screens share one resident browser and are revealed only when their state, resources and first frame are ready.

• Lifecycle-aware pages. Animation, WebGL and video pause when a screen is covered, and hidden browsers stop rendering.

• Adaptive frame rate that follows the game, with a render scale per interface.

• Measure it yourself with the diagnostics overlay, Chrome DevTools and the benchmark scene in the sample.

Orion Station sample

A Blueprint-only sample game with a menu, inventory, saved settings, a collection mission and WorldUI, plus ten showcase rooms, four themes and two languages. All Blueprints and the full frontend source are included. The playable demo above is this sample, packaged.

Requirements

• Unreal Engine 5.8 on Windows 64-bit, for development and packaged games.

• First use: click the WebUIStudio toolbar button to download two companion programs (about 160 MB) from the publisher's GitHub release: the runtime browser helper and WebUIStudio. Files are verified by SHA-256, nothing downloads automatically, and an offline import is documented.

• Packaging needs the Visual Studio C++ toolchain and the Windows SDK. Building web pages needs Node.js 22 LTS or newer.

• AI features need your own Codex or Claude desktop app and account.

• InstantScreen needs a small C++ host. A web page cannot blur or read the game image behind it.

What you get

Full C++ source for every module, the WebUIStudio app, the AI Creation Skill, the web project template, and a manual in English and Simplified Chinese with four tutorials.

Start with Orion Station, restyle it, and wire it to your own game.