Determine length of Curve in Blender

First i will do a mathless version using a convoluted, yet pretty fast, way to get at the global length of a curve.

This might be a little excessive, but here is a small script that you run from text editor, then in 3dview a button appears when you select a curve.

When pressed:
- it duplicates the curve as a mesh,
- applies all transforms to the duplicate (for global coordinate values)
- sums the collected the edges of this mesh
- prints the length to the terminal + copies value to clipboard
- then deletes duplicate mesh
- selects original curve again

	import bpy
	import mathutils
	from mathutils import Vector
	def get_length(context):
	obj_name_original = context.active_object.name
	bpy.ops.object.duplicate_move()
	# the duplicate is active, apply all transforms to get global coordinates
	bpy.ops.object.transform_apply(location=True, rotation=True, scale=True)
	# convert to mesh
	bpy.ops.object.convert(target='MESH', keep_original=False)
	_data = context.active_object.data
	edge_length = 0
	for edge in _data.edges:
	vert0 = _data.vertices[edge.vertices[0]].co
	vert1 = _data.vertices[edge.vertices[1]].co
	edge_length += (vert0-vert1).length
	# deal with trailing float smear
	edge_length = '{:.6f}'.format(edge_length)
	print(edge_length)
	# stick into clipboard
	context.window_manager.clipboard = edge_length
	bpy.ops.object.delete()
	context.scene.objects.active = context.scene.objects[obj_name_original]
	context.object.select = True
	class ButtonOne(bpy.types.Operator):
	"""Defines a button"""
	bl_idname = "scene.dostuff"
	bl_label = "Sometype of operator"
	def execute(self, context):
	get_length(context)
	return{'FINISHED'}
	class OperatorPanel(bpy.types.Panel):
	"""Creates a Panel in the Object properties window"""
	bl_label = "Some Utility"
	bl_idname = "OBJECT_PT_somefunction"
	bl_space_type = "VIEW_3D"
	bl_region_type = "UI"
	bl_context = "object"
	def draw(self, context):
	layout = self.layout
	obj = context.object
	row = layout.row()
	# display label and button
	if not obj.type == 'Curve' and context.active_object.select:
	row.label(text="Active object is: " + obj.name)
	self.layout.operator("scene.dostuff", text='Print length to console')
	classes = [OperatorPanel, ButtonOne]
	def register():
	for i in classes:
	bpy.utils.register_class(i)
	def unregister():
	for i in classes:
	bpy.utils.unregister_class(i)
	if __name__ == "__main__":
	register()

view raw calculate curve length .py hosted with ❤ by GitHub