[component_ghpython] Useful GH_Python components #grasshopper #python

component_ghpython.py

# Switch on and off of the global timer
# Needs update with Rhino 7

import Grasshopper as gh
# Get the Grasshopper document and objects
ghDoc = ghenv.Component.OnPingDocument()
ghObjects = ghDoc.Objects
# Iterate the GH objects, check type and reset data recorders
for obj in ghObjects:
    if type(obj) is gh.Kernel.Special.GH_Timer:
        if Toggle:
            obj.Locked = True
            obj.ExpireSolution(True)
        else:
            obj.Locked = False
            obj.ExpireSolution(True)


# RegionContainment defines enumerated values for curve relationships but I just don't get it.
# https://developer.rhino3d.com/api/RhinoCommon/html/T_Rhino_Geometry_RegionContainment.htm

from Rhino.Geometry import *
from Rhino.RhinoDoc import ActiveDoc as rhdoc
tol = rhdoc.ModelAbsoluteTolerance
ids = range(len(crvs))
# initialize with dictionary of sets containing its own key
# i.e all curves in separate clusters
clusters = {i: set([i]) for i in ids}

rtree = RTree()
for i, crv in enumerate(crvs):
    # populate the RTree with bounding boxes
    rtree.Insert(crv.GetBoundingBox(True), i)

def check_containment(crvA, crvB):
    # checks if either A contains B or B contains A
    # relatively expensive, so further optimizations can be made here eg. for polylines
    rg = Curve.PlanarClosedCurveRelationship(crvA, crvB, Plane.WorldXY, tol)
    return (rg in (RegionContainment.AInsideB, RegionContainment.BInsideA))

def callback(sender, e):
    a, b = e.Id, e.IdB
    if a == b:
        return
    if b in clusters[a] or a in clusters[b]:
        return
    if check_containment(crvs[a], crvs[b]):
        clusters[a].add(b)
        clusters[b].add(a)

RTree.SearchOverlaps(rtree, rtree, 0.01, callback) # O(n)

# iterate through the clusters from the highest to lowest index
for i in reversed(ids):
    # still O(n) despite nested for loop, because inner loop is ~O(1)
    for j in list(clusters[i]):  # create new list to avoid changing the iterable
        # merge with sets of a greater index
        if j > i:
            try:
                clusters[i].update(clusters.pop(j))
            except KeyError:  # j has already been popped
                pass

mapping = [0] * len(crvs)
for k, vals in clusters.items():
    for v in vals:
        mapping[v] = k