Tracing

At some point you may find that you need to produce an IPE vector diagram from a bitmap image. For example, in the past I have produced a 3D model in Blender and traced over it in Ipe to get a line drawing. This is pretty easy, if sometimes tedious. Here's how.

Import the image

Choose Ipelets->Insert Image and then the appropriate image option. Move and resize the image appropriately.

Organise Layers

Create a new layer (Layer->New Layer). Select this layer with the left mouse button in the 'Layers' dock, and enable the checkbox next to it so that it is visible. Now right click on the first layer (called 'alpha'). Select 'Lock'. This makes it uneditable so the image you are tracing is a fixed background.

Trace the image

Now you can add lines, polygons, circles, etc over the image as you see fit.

Automatic Tracing

You may find the little program potrace useful.