Tracing object's path

Question

I am working on a scientific visualization.

Scene is like there is a sphere and I want to mark down the path that it passes through.

Sphere follows a completely unknown path, so I can't draw it manually. Glad to get help!!!

Answer 1

Motion Paths

From the blender user manual

Editor: 3D View, Properties editor Mode: Object Mode Panel: Properties editor ‣ Object ‣ Motion Paths

The Motion Paths tool allows you to visualize the motion of points as paths over a series of frames. These points can be object origins and bone joints. Motion Paths

To create or remove motion paths, it is necessary to first select the bones. Then:

• To show the paths (or update them, if needed), click on the Calculate Path button.
• To hide the paths, click on the Clear Paths button.

These are display only, to get them as actual object you'd need to convert them using a script, there's one in this blender artists thread

Unfortunately this won't work in blender 2.81, but with a slight modification it does, here's the updated version:

## path from -calculated- motion path

import bpy
ob = bpy.context.object
mp = ob.motion_path

if mp:
    path = bpy.data.curves.new('path','CURVE')
    curve = bpy.data.objects.new('Curve',path)
    bpy.context.scene.collection.objects.link(curve)
    path.dimensions = '3D'
    spline = path.splines.new('BEZIER')
    spline.bezier_points.add(len(mp.points)-1)

    for i,o in enumerate(spline.bezier_points):
        o.co = mp.points[i].co
        o.handle_right_type = 'AUTO'
        o.handle_left_type = 'AUTO'