import rhinoscriptsyntax as rs
import math

def generate_spiral_points(seeds_count, sphere_radius):
    points = []
    phi = math.pi * (3. - math.sqrt(5.))   # golden angle
    dz = 2.0 / seeds_count                 # Incremental step for z
    z = 1.0 - dz / 2.0                     # slightly below top of the sphere
    for i in range(seeds_count):
        radius_at_z = math.sqrt(1 - z * z) # Radius at z
        theta = phi * i                    # Angle 
        x = math.cos(theta) * radius_at_z
        y = math.sin(theta) * radius_at_z

        points.append((x * sphere_radius, y * sphere_radius, z * sphere_radius)) # points on sphere
        z -= dz                             # Move down the sphere
    return points

def draw_seed(point, sphere_radius, seed_length=1.0, seed_radius=0.5):
    direction = rs.VectorUnitize(point)
    end_point = rs.VectorAdd(point, rs.VectorScale(direction, seed_length)) # end point seed line
    rs.AddLine((0,0,0), end_point)          # seed line
    for i in range(10):                     # lines in seed head
        angle = math.pi * i / 10            # Angle increment
        for j in range(20):                 # lines around seed head
            theta = 2 * math.pi * j / 20    # Angle around seed head
            x = math.sin(angle) * math.cos(theta) * seed_radius
            y = math.sin(angle) * math.sin(theta) * seed_radius
            z = math.cos(angle) * seed_radius
            seed_point = rs.VectorAdd(end_point, (x, y, z))
            if rs.Distance((0,0,0), seed_point) > sphere_radius + seed_length:
                rs.AddLine(end_point, seed_point)

def draw_spiral_structure(seeds_count=100, sphere_radius=1):
    rs.DeleteObjects(rs.AllObjects())
    sphere = rs.AddSphere((0, 0, 0), sphere_radius)             # main sphere
    points = generate_spiral_points(seeds_count, sphere_radius) # points on sphere
    for point in points:                                        # spirale points
        rs.AddPoint(point)
    for point in points:                                        # seeds
        draw_seed(point, sphere_radius)

draw_spiral_structure(seeds_count=100, sphere_radius = 3)       # dandelion