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Image Tracking ​

An Image Tracking project anchors 3D content to a printed or on-screen image. When the runtime detects a registered image target through the camera, it places the matching anchor entity at that target's position and orientation.

Use this for posters, business cards, product packaging, museum exhibits, and any AR experience tied to a printed surface.

Image Tracking Example Preview

What's different in this project type ​

When you open an image-tracking project, the editor changes in three ways:

  1. Image targets are first-class entities in the hierarchy. Each anchor represents one image and contains the children that should appear when that image is detected.
  2. A floating Compile Targets button appears in the viewport overlay. It opens the image compilation modal which packages your image targets into a binary the runtime can load.
  3. The Image Targets panel lives in the inspector when an image-target entity is selected. From there you upload reference images, set physical sizes, and preview tracking quality.

Image Target Compile Modal

Workflow ​

  1. Add an Image Target entity from the toolbar + menu (or hierarchy panel). The editor creates an image-target anchor at the scene root.
  2. Select the anchor and use the Image Targets panel in the inspector to upload one or more reference images. For each, set its real-world physical width.
  3. Add child entities under the anchor. Anything you parent to it becomes visible only when that image is detected.
  4. Compile targets — click the floating Compile Targets button in the viewport. The compilation modal runs through tracker quality analysis and writes the compiled binary into bin/targets/.
  5. Preview — press the preview button. The runtime loads the compiled targets and starts the device camera.

Image Target Panel

Tips ​

  • High-contrast, feature-rich images track best. Photos of faces, gradients, and large flat colors are weak targets.
  • Keep the physical size field accurate — this is what the runtime uses to scale your 3D content to the printed image.
  • Children of an image-target anchor inherit its transform. Position objects in local space relative to the anchor, not world space.
  • Recompile targets whenever you add or change reference images.