seam_cmd.py

from __future__ import division
import rhinoscriptsyntax as rs

__commandname__ = "tbr_seam"

def get_plane(c_0, c_1):
    """
    Given two curves it gives you a normal vector to them
    """
    pass

def point_to_coordinates(p):
    return p.X, p.Y, p.Z

def coordinates_to_point(xyz):
    return rs.coerce3dpoint(xyz)

def normalize(p):
    l = (p.X**2 + p.Y**2 + p.Z **2) ** 0.5
    return p / l

def get_direction(c):
    """
    Given a curve it gives your a length one vector
    describing it orientation
    """
    p0, p1 = rs.CurvePoints(c)
    v = (p1 - p0) / rs.Distance(p0, p1)
    return v

def cross_product(u, v):
    u = point_to_coordinates(u)
    v = point_to_coordinates(v)
    dim = len(u)
    s = []
    s.append(u[1]*v[2] - u[2]*v[1])
    s.append(u[2]*v[0] - u[2]*v[0])
    s.append(u[0]*v[1] - u[1]*v[0])
    return coordinates_to_point(s)

def get_edge(message):
    edges = rs.GetEdgeCurves(message, min_count=1, max_count=1)
    curve_id, parent_id, selection_point = edges[0]
    return parent_id, curve_id

def fillet_corner(c0, c1, radius=7.):
    p0, p1, _, _, _, _ = rs.CurveFilletPoints(c0, c1 , radius, return_points=False)
    c0k, c0d = rs.SplitCurve(c0, rs.CurveClosestPoint(c0,p0), delete_input=True)
    c1d, c1k = rs.SplitCurve(c1, rs.CurveClosestPoint(c1,p1), delete_input=True)
    rs.DeleteObject(c0d)
    rs.DeleteObject(c1d)
    fillet = rs.AddFilletCurve(c0k, c1k, radius=radius, base_point0=p0, base_point1=p1)
    return rs.JoinCurves([c0k, fillet, c1k], delete_input=True)

def get_type(obj):
    return {
    0:           "Unknown object",
    1:           "Point",
    2:           "Point cloud",
    4:           "Curve",
    8:           "Surface",
    16:          "Polysurface",
    32:          "Mesh",
    256:         "Light",
    512:         "Annotation",
    4096:        "Instance or block reference",
    8192:        "Text dot object",
    16384:       "Grip object",
    32768:       "Detail",
    65536:       "Hatch",
    131072:      "Morph control",
    134217728:   "Cage",
    268435456:   "Phantom",
    536870912:   "Clipping plane",
    1073741824:  "Extrusion"}[rs.ObjectType(obj)]

def extrude_both_sides(curve, p, direction, length=100):
    e0 = rs.ExtrudeCurveStraight(curve, p, p+direction * length)
    rs.CapPlanarHoles(e0)
    e1 = rs.ExtrudeCurveStraight(curve, p, p-direction * length)
    rs.CapPlanarHoles(e1)
    rs.DeleteObject(curve)
    return rs.BooleanUnion([e0,e1], delete_input=True)

def draw_rounded_trapesoid(p,v,u,trap):
    top = rs.AddCurve([p,p+v-trap], degree=3)
    right = rs.AddCurve([p+v-trap,p+v+u+trap], degree=3)
    bottom = rs.AddCurve([p+v+u+trap,p+u], degree=3)
    left = rs.AddCurve([p+u,p], degree=3)
    top_right = fillet_corner(top,right)
    top_right_bottom = fillet_corner(top_right, bottom)
    return rs.JoinCurves([top_right_bottom, left], delete_input=True)


def RunCommand(is_interactive):
    obj_0, seam_edge = get_edge("Get seam edge")
    obj_1, other_seam_edge = get_edge("Opposite seam eedge")
    _, width_edge  = get_edge("Tooth edge")
    #widht =  rs.GetInteger("width")
    n_teeth = 5

    assert obj_0 != obj_1
    assert get_type(obj_0) == "Polysurface"
    assert get_type(obj_1) == "Polysurface"
    assert seam_edge != other_seam_edge
    #TODO check it has the same start and end points
    assert get_type(seam_edge) == "Curve"
    assert get_type(other_seam_edge) == "Curve"
    print("assertion passed")

    p0, p1 = rs.CurvePoints(seam_edge)
    u = get_direction(seam_edge) * rs.Distance(p0, p1) / n_teeth
    v = get_direction(width_edge) * 15
    w = normalize(cross_product(u,v))
    p = p0
    rs.DeleteObjects([seam_edge, other_seam_edge, width_edge])
    trap = 0.2 * u
    print("computed u,v and   w")
    for i in range(n_teeth):
        if i % 2 == 0:
            tooth_curve = draw_rounded_trapesoid(p,v,u,trap)
            long_tooth = extrude_both_sides(tooth_curve, p0, w)
            tooth_0 = rs.BooleanIntersection(obj_0, long_tooth, delete_input=False)
            tooth_1 = rs.CopyObject(tooth_0)
            rs.DeleteObject(long_tooth)
            obj_0 = rs.BooleanDifference(obj_0, tooth_0, delete_input=True)
            obj_1 = rs.BooleanUnion([obj_1, tooth_1], delete_input=True)
        else:
            tooth_curve = draw_rounded_trapesoid(p,-v,u,trap)
            long_tooth = extrude_both_sides(tooth_curve, p0, w)
            tooth_0 = rs.BooleanIntersection(obj_1, long_tooth, delete_input=False)
            tooth_1 = rs.CopyObject(tooth_0)
            rs.DeleteObject(long_tooth)
            obj_1 = rs.BooleanDifference(obj_1, tooth_0, delete_input=True)
            obj_0 = rs.BooleanUnion([obj_0, tooth_1], delete_input=True)

        p = p + u
    print("Created seam")

if __name__ == "__main__":
    RunCommand(True)