Using a moving empty to draw a line

I haven’t done much animating with Blender but I’m trying out stuff. Is there a way to make an animated empty draw a line as it moves?

I tried using a bezier curve to replicate the empty’s path (which doesn’t exist as I hand keyframed the empty’s movements) and then using a cylinder and array + curve modifiers to make it look like the empty is drawing a line but this is far too difficult to do by hand. Not to mention the bezier curve is far from perfect. Is there an easier way to make this? Preferably automatically.

I guess some sort of particle system could work but wouldn’t it be rather resource intensive to use particles to draw a long lasting solid line?

You could use the dynamic paint feature. Add a small mesh in place of or parented to your empty to act as the brush…0l3.54624663.54628854.0.54629200.…0.0…1ac.1.HOFJQIimdik

Looks very promising indeed but it needs a canvas. I need this three dimensional line to be drawn into 3D space.

sounds like a job for a circle that gets extruded down a path using an animated evaluation time

The most straightforward “particle system” is to apply the animation to a mesh object consisting of a single vert, and using Duplication: Frames (in the Object-settings) and Make Duplicates Real (spacebar-search it).
Then you can stitch the verts together somehow (I tried using edges instead of verts, and Looptools: Loft), and convert them to a path.
Sorry for the vague description, and it doesn’t really help with the “writing” part, but maybe the concept can be useful.

The bTrace addon may be what you want. It doesn’t work with empties, but it can work with invisible meshes.

Install the add-on, animate your tracing object, and under the “Btrace: panel” in the tools panel of your 3d view, select “mesh follow,” then below that, “object” (if you want the trail to trace the center of your object,) then enter your start and end frames of your animation, and then add “grow curve,” set the duration and start frame to match the time and duration of your animation, set the “fade” time to zero, then back up top, hit “Run!”

I urge you to play with the settings until you find what you are looking for; I think you probably will!

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