Arrow modeling

About

Note

This example is derived from the example from geonodes, you can compare pynodes with geonodes in this example.

Calculate coordinate of arrow

arrow_coord

from pynodes import *
from pynodes.math import *

@tree
def arrow_coord(
    l: Float = ("Length", 1, 0),
    r: Float = ("Radius", 0.1, 0.001),
    s: Float = ("Head size", 2, 1.001),
    α: Angle = ("Angle", radians(20), radians(10), radians(89.999)),
    k: Float = ("Recess", 0.5, 0, 0.99),
):
    rh = r * s

    tg = tan(α)

    hh = rh / tg
    z0 = l - hh

    h = r / tg
    d = k * h * (s - 1)

    z1 = z0 + d
    z2 = z0 + k * h * s

    return z1, z2

coordinate Correction

coord_correction

@tree
def coord_correction(vertices: Integer = (12, 3)):

    f = 1 / cos(pi / vertices)**2

    position = InputPosition()

    corrected_pos = position * (f, f, 1)

    return corrected_pos

Arrow Modeling

arrow_modeling

@tree
def arrow_modeling( # name(Optional), default, min(Optional), max(Optional)
    l: Float = ("Length", 1, 0),
    r: Float = ("Radius", 0.1, 0.001),
    s: Float = ("Head size", 2, 1.001),
    α: Angle = ("Angle", radians(20), radians(10), radians(89.999)),
    k: Float = ("Recess", 0.5, 0, 0.99),
    vertices: Integer = (12, 3),
    target: Object = None
):
    with frame("The start circle from bottom"):

        arrow = MeshCircle(vertices=vertices, radius=r, fill_type='NGON')

    with frame("Calculate z1 and z2"):

        z1, z2 = arrow_coord(l, r, s, α, k)

    with frame("Extrude the arrow shaft"):

        arrow, top, sides = arrow.extrude_edges(offset_scale=z1)

    with frame("Set the material of the arrow shaft"):

        arrow.set_material("Arrow Shaft")

    with frame("Correct the position of the arrow head"):

        corrected_pos = coord_correction(vertices)

    with frame("Extrude the arrow inner part of the arrow head"):

        arrow, top, sides = arrow[top].extrude_edges(offset=corrected_pos - (0, 0, z2), offset_scale=s - 1)

    with frame("Set the material of the arrow head"):

        arrow[sides].set_material("Arrow Head")

    with frame("Extrude the outer part of the arrow head"):

        arrow, top, sides = arrow[top].extrude_edges(offset=(0, 0, l) - corrected_pos)

    with frame("The location the arrow should point to"):

        loc = target.object_info("RELATIVE").location

    with frame("Rotate the arrow to the location of the target object"):

        rot_track = loc.align_euler_to_vector("Z")

        arrow.transform(rotation=rot_track)

    return arrow

Arrow Materials

Arrow materials

@tree
def arrow_head():
    """@material"""

    shader = BsdfPrincipled(base_color="#3ac463")

    return shader


@tree
def arrow_shaft():
    """@material"""

    shader = BsdfPrincipled(base_color="#2c6397")

    return shader