Arc Length

Arc Length
 1# This example creates an arc and displays the length of the arc in the
 2# output toolbox. The length of the arc is then modified and displayed
 3# again in the output toolbox.
 4
 5# Create a local variable for the output toolbox
 6ot = impact.gui.output_toolbox
 7
 8# Clear the output toolbox
 9ot.clear()
10
11# Create a local variable for the active drawing
12ad = impact.active_drawing
13
14# check there is an active drawing
15if ad.isNone():
16
17    # display a message in the output toolbox
18    ot.add("Unable to continue: there is no active drawing")
19
20else:
21
22    # create a local variable for the active block
23    ab = ad.active_layer.active_block
24
25    # move to the origin of the active block
26    ab.move_ad(0, 0)
27
28    # create a local variable for the radius
29    radius = 50
30
31    # create a vector for the offset
32    offset = impact.creator.vector(radius,radius)
33
34    # create a clockwise large arc
35    arc1 = ab.arc(offset, radius, 0, 1)
36
37    # display the length of the arc in the output toolbox
38    ot.add(arc1.length)
39
40    # modify the length of the arc
41    arc1.length = arc1.length * 2
42
43    # display the length of the arc in the output toolbox
44    ot.add(arc1.length)