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Annotate spheres on arbitrary planes

Summary

Annotating spheres in 3D is useful for defining regions of interest around a point. Here we describe how to annotate a sphere on an arbitrary plane in an image.

Instructions

  1. Open the sphere_annotator.py example from the examples folder. The viewer is initialized in 3D rendering mode in plane rendering mode. We are viewing a 3D volume with one plane being actively rendered.

    example opened

  2. Activate the plugin. Select the plane layer for the "image layer" and click the "activate" button. This will add points to the Points layer based on the intersection of the click ray with the currently rendered orange layer.

    select layer

  3. You can translate the rendered orange play along its normal vector by holding the shift key while clicking with the left mouse button and dragging the plane.

  4. You can add a sphere on the rendered play by holding alt and clicking on the plane with the left mouse button. If you alt+click again, it will reposition the sphere.

  1. You can adjust the radius of the sphere by presing the r key and the sphere will snap to the position where your mouse pointer intersects the rendered plane.

  1. You add a new point by pressing the n key and repeating steps 5 and 6.