When does an interactive or 3D website work?

What makes a site interactive?

An interactive site answers the visitor's movement: scroll, cursor, touch. The answer can be as small as a heading easing in, or as large as the whole page moving like a film.

In practice there are three layers: scroll-tied storytelling, video played by scrolling, and 3D scenes drawn in real time in the browser. A project can use one, two or all three.

Scroll-tied storytelling and video

This is the most common layer and often the most efficient. The page tells a story from top to bottom; sections, figures and images enter as you scroll. Libraries such as GSAP and Lenis keep the motion smooth and free of jitter.

On A'lâ Çekmeköy Nefes the project film advances with the scroll; glass panels carry the project's figures (14,300 m² of land, 9 blocks, 72 homes) and its living spaces, with the enquiry form always at hand. The visitor does not watch the film, they move through it at their own pace.

WebGL and Three.js: real-time scenes in the browser

WebGL lets the browser draw 3D graphics on the graphics card; Three.js is the most widely used library on top of it. With them, particle systems, shader effects and 3D models the visitor can turn run right inside the site.

In MODD-AI Web Experience generative systems form the texture of the page and the scroll sets the timing of the story; the landing is not a brochure but proof of the product itself. The particle bust on this site's home page and the six live experiments on the Lab page are built with the same technology, Three.js and React Three Fiber.

3D models and digital twins

A place, a building or a product can also be made explorable in the browser. That takes model files (usually GLB) slimmed for the web, a well-planned loading order and data wired into the scene.

In my 3D Web & Digital Twin research I treat a place's digital twin not just as geometry but as a surface where data, state and interaction live in one scene: GLB pipelines, CRM connections and VR/AR surfaces.

When does it work?

Interactivity adds value when it serves a purpose. Good candidates:

• Work that sells a visual experience: residential projects, architecture, automotive, fashion, product launches.
• Brands that need to stand apart, where the first impression drives the sale.
• Cases where the best way to explain a system or product is to show it.
• Short-lived campaign and launch sites.

When does it get in the way?

On information-heavy sites (large product catalogues, content updated often, pages where visitors need to find something fast) heavy motion becomes a burden. There it is better to keep interactivity to small touches.

Phone performance

Phones are where interactive sites struggle most. A scene that runs smoothly on desktop can stutter on a phone's graphics chip, and some Android graphics processors behave differently.

So the scene should be simplified to the device's power, heavy parts loaded after the first screen, visitors who prefer reduced motion shown a calm version, and the site tried on several real phones before launch. Working in a simulator is not enough.

Does it clash with search engines?

It does not have to. The trouble starts when text is baked into a canvas or a video: search engines and AI bots cannot read writing inside a picture.

Built right, the scene is one layer and the text another: headings, descriptions and project details sit on the page itself, ready from the server. On this site the text beside every 3D scene is served that way, and Google can read the site without running the animations.

The right brief

Before talking about an interactive site, settling these speeds things up:

• What should visitors do after the site: fill a form, call, buy?
• Is the material ready: renders, video, 3D models, photography?
• Do most visitors come on a phone?
• Is it for a short launch, or a corporate site used for years?
• A few example sites you like and dislike.

Short answers