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multi-threaded python sample
import System.Threading.Tasks as tasks
import Rhino
import rhinoscriptsyntax as rs
import time, math
import scriptcontext
def radial_contour(brep, parallel, slice_count=360):
"""Generate series of curve slices through a brep by rotating a plane
multiple times and intersecting that plane with the brep. This function
demonstrates the use of .NET Parallel.For in order to run the function
in parallel
brep = the Brep to contour
parallel = If True, this function will compute intersections in multiple
threads using Parallel.For. If False, all intersections will be performed
on a single thread
slice_count = number of slices to generate. Slices are evenly distributed
over a full circle
if not brep: return
results = range(slice_count)
rotation_axis = Rhino.Geometry.Vector3d(0,1,0)
intersect_tol = scriptcontext.doc.ModelAbsoluteTolerance
# local function that does the intersection work. This function is called
# once for each angle in "slice_count" and needs to be thread-safe
def slice_brep_at_angle(i):
angle_rad = i/slice_count * 2.0 * math.pi
plane = Rhino.Geometry.Plane.WorldXY
plane.Rotate(angle_rad, rotation_axis, Rhino.Geometry.Point3d.Origin)
rc, crvs, pts = Rhino.Geometry.Intersect.Intersection.BrepPlane(brep, plane, intersect_tol)
if rc: results[i] = crvs
else: results[i] = None
if parallel:
tasks.Parallel.ForEach(xrange(slice_count), slice_brep_at_angle)
for i in xrange(slice_count): slice_brep_at_angle(i)
return results
if __name__=="__main__":
brep = rs.GetObject("Select Brep", rs.filter.polysurface)
brep = rs.coercebrep(brep)
if brep:
# Make sure the Brep is not under the control of the document. This is
# just done so we know we have a quick to access local copy of the brep
# and nothing else can interfere while performing calculations
#run the function on a sinlge thread
start = time.time()
slices1 = radial_contour(brep, False)
end = time.time()
print "serial = ", end-start
#run the function on mulitple threads
start = time.time()
slices2 = radial_contour(brep, True)
end = time.time()
print "parallel = ", end-start
if slices2:
for curveset in slices2:
if curveset:
for curve in curveset: scriptcontext.doc.Objects.AddCurve(curve)
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