Build a 360° Panorama Viewer in the Browser with Three.js

Panoramic browsing in a browser may sound mysterious, but once you understand the underlying principles, implementing a 360° viewer becomes straightforward.

Background

Recent H5 pages have leveraged panoramic image technology for eye‑catching promotions, such as celebrity‑themed tours or virtual headquarters visits. These pages achieve a striking effect by stitching wide‑angle photos into a seamless sphere that users can explore.

What Is a Panorama?

360° panoramas, also called spherical or panoramic view images, are created by capturing a scene from multiple angles, stitching the photos together, and displaying them with a playback program to form a three‑dimensional virtual representation. – Baidu Baike

To turn such an image into an interactive web experience, you need to post‑process the stitched photo, load it into a viewer, and render it with WebGL.

Using Three.js for Panorama Rendering

Three.js provides several camera types: CubeCamera , PerspectiveCamera , and OrthographicCamera . For a standard panoramic viewer we use a PerspectiveCamera , which mimics human vision.

Creating a perspective camera requires only a single line of code:

var camera = new THREE.PerspectiveCamera(fov, aspect, near, far);

Where fov is the field of view angle, aspect is the width‑to‑height ratio, near and far define the clipping planes.

These parameters set the camera’s intrinsic properties but not its position or orientation. In Three.js you position the camera with camera.position (a three‑dimensional vector) and direct its view using camera.lookAt(vector). The camera’s up direction is controlled by camera.up, which determines how the scene is rotated around the viewing axis.

By placing the panoramic texture on the inner surface of a sphere (or cylinder) and positioning the camera at the sphere’s center, users can rotate the view to explore the entire environment. The up vector ensures the horizon stays level, preventing disorienting flips.

Below is an illustration of the camera setup:

With the camera configured and the panoramic texture mapped correctly, the viewer can render a smooth, interactive 360° experience that works on modern browsers and mobile devices.