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attractor point

Glenn demonstrates a common way of manipulating geometry in a point list through something called an Attractor Point.

what’s in this video

In this video I demonstrate a common way of manipulating geometry using an attractor point. During the demonstration I introduce a function that we have not used before in the course—the rs.Distance function.

check your knowledge

[Pause the video and take a moment to practice using attractor points]

Use the attractor point system in the Nested Loop: 2D Point Matrix code to manipulate the rotational angle of the transformed geometry.

tutorial code

#ATTRACTOR POINT
import rhinoscriptsyntax as rs

#create an empty list
ptList = []

#input a point to use as an attractor
attrPt = rs.GetObject('select an attractor point',rs.filter.point)

#incremental loop to generate points
for i in range(10):
 for j in range(10):
 #define x in terms of i
 #define y in terms of j
 x = i
 y = j
 z = 0
 
 rs.AddPoint(x,y,z)
 #rs.AddTextDot((x,y,z), (x,y,z)) 
 
 #save point values in a list
 ptList.append((x,y,z))
 
#loop through point list and print out index number and values
for i in range(len(ptList)):
# print i, ':', ptList[i]
# rs.AddTextDot(i, ptList[i])
 
 ####CREATE TRANSFORMATION OF GEOMETRY####
 #measure distance between attractor point and current point in the list
 distance = rs.Distance(ptList[i], attrPt)
 print distance/20
 #create circle using distance value as radius
 rs.AddCircle(ptList[i], distance/20)