createSpline dynamic

import c4d
from c4d import SplineObject
from c4d import documents
from c4d import BaseTag
from c4d import BaseSelect

doc = c4d.documents.GetActiveDocument()

def add_spline(number_points, spline_length):
    '''Returns a linear spline of a specified length that starts at the origin and extends through the y-axis'''
    segment_length = spline_length / (number_points - 1)
    spline = c4d.SplineObject(int(number_points), c4d.SPLINETYPE_LINEAR)

    index = 0
    while index <= (int(number_points) - 1):
        if index == 0:
            spline.SetPoint(index, c4d.Vector())
            index += 1
        else:
            point_pos = c4d.Vector(0, 0, int((segment_length * index)))
            spline.SetPoint(index, point_pos)
            index += 1
    return spline

def main():
    main_null = c4d.BaseObject(c4d.Onull)
    # function creates a linear spline
    spline = add_spline(50, 500)

    # create tags
    constraint_tag_start = c4d.BaseTag(1018074)   # 1018074 //Constraint
    constraint_tag_end = c4d.BaseTag(1018074)   # 1018074 //Constraint
    dynamics_tag = c4d.BaseTag(1018068)     # 1018068 //Spline Dynamics

    # add dynamics tag to spline
    spline.InsertTag(dynamics_tag)

    # create null
    null_start = c4d.BaseObject(c4d.Onull)
    null_end = c4d.BaseObject(c4d.Onull)
    null_end.SetAbsPos(c4d.Vector(0,0,500))

    # insert null into anchor field for constraint tag
    constraint_tag_start[c4d.HAIR_CONSTRAINTS_TAG_ANCHOR_LINK] = null_start
    constraint_tag_end[c4d.HAIR_CONSTRAINTS_TAG_ANCHOR_LINK] = null_end

    # add constraint tag to spline
    spline.InsertTag(constraint_tag_end)
    spline.InsertTag(constraint_tag_start)


    # select point 0 on spline (at position 0, 0, 0)
    all_points = spline.GetPointS()
    all_points.Select(0)

    # Add the spline and null to the scene
    doc.InsertObject(spline)
    doc.InsertObject(null_start)
    doc.InsertObject(null_end)
    doc.InsertObject(main_null)

    spline.InsertUnder(main_null)
    null_start.InsertUnder(main_null)
    null_end.InsertUnder(main_null)

    # set the spline to be the active object
    doc.SetActiveObject(spline, 1)

    # get all tags attached to spline
    tags = spline.GetTags()

    #Before we attempt to execute any buttons. Let's first update C4D about all these changes we've made first
    c4d.DrawViews(c4d.DRAWFLAGS_ONLY_ACTIVE_VIEW|c4d.DRAWFLAGS_NO_THREAD|c4d.DRAWFLAGS_NO_REDUCTION|c4d.DRAWFLAGS_STATICBREAK) #Update cinema 4d

    # push the button HAIR_CONSTRAINTS_TAG_SET_ANCHOR
    c4d.CallButton(tags[0], 5000)   # 5000 //HAIR_CONSTRAINTS_TAG_SET_ANCHOR

    all_points.DeselectAll()
    all_points = spline.GetPointS()
    all_points.Select(49)

    #Before we attempt to execute any buttons. Let's first update C4D about all these changes we've made first
    c4d.DrawViews(c4d.DRAWFLAGS_ONLY_ACTIVE_VIEW|c4d.DRAWFLAGS_NO_THREAD|c4d.DRAWFLAGS_NO_REDUCTION|c4d.DRAWFLAGS_STATICBREAK) #Update cinema 4d

    c4d.CallButton(tags[1], 5000)   # 5000 //HAIR_CONSTRAINTS_TAG_SET_ANCHOR


    c4d.EventAdd()

if __name__ == '__main__':
    main()