I am new to Blender and I want to create an array of 3D arrows; the array itself is 2*2 (constant space between each object) but the arrows are 3D.
I hope to write a python code for it but I don't know where to start. There is a code in the following link for a single 3D arrow, but I'm afraid I cannot use it.
Here's something I wrote that I think you might find useful. v0, v1, and v2 are three corners of a square and I used nested for loops to create an array of arrows. To create the arrows themselves, I wrote a mesh-from-scratch function "createArrow". Let me know if I need to fix anything.
import bpy
from math import *
from mathutils import Vector
def createArrow(tubeRadius, arrowLength, headLength, tubeLength, tubeAcross, tubeAround, headAround, headRadius, arrows):
verts = []
edges = []
faces = []
#append tube verticies 0 thru (tubeAcross x tubeAround - 1)
for i in range(tubeAcross):
v1 = tubeLength * (i / (tubeAcross - 1)) #- length/2
for j in range(tubeAround):
angle = 2 * pi * j / tubeAround
v2 = tubeRadius * cos(angle)
v3 = tubeRadius * sin(angle)
verts.append([v1, v2, v3])
index1 = tubeAround * i + j
index2 = tubeAround * i + j + 1
if index2 == (i + 1) * tubeAround:
index2 = i * tubeAround
edge = [index1, index2]
edges.append(edge)
#append cone verts (tubeAcross x tubeAround) thru (tubeAcross x tubeAround + coneAround + 1) (exctra 1 for the tip)
for i in range(headAround):
angle = 2 * pi * i / headAround
v1 = tubeLength
v2 = headRadius * cos(angle)
v3 = headRadius * sin(angle)
verts.append([v1, v2, v3])
verts.append([arrowLength, 0, 0])
#append tube faces:
# for i in range of number of faces (added 1 for the circle face)
for i in range(tubeAround * (tubeAcross - 1) + 1):
face = []
if i == 0:
# make face out of first slicesAround edges:
for j in range(tubeAround):
face.append(edges[j][0])
else:
face = [edges[i - 1][0], edges[i - 1][1], edges[i - 1 + tubeAround][1], edges[i - 1 + tubeAround][0]]
faces.append(face)
#append face for back of cone:
face = []
for i in range(headAround):
face.append(tubeAround*tubeAcross + i)
faces.append(face)
#append cone faces:
for i in range(headAround):
index1 = tubeAcross * tubeAround + i
index2 = tubeAcross * tubeAround + i + 1
index3 = tubeAcross * tubeAround + headAround
if index2 == index3:
index2 = index2 - headAround
face = [index1, index2, index3]
faces.append(face)
mesh = bpy.data.meshes.new("Arrow")
arrow = bpy.data.objects.new("Arrow", mesh)
#col = bpy.data.collections.get("Collection")
#col.objects.link(bendableArrow)
arrows.objects.link(arrow)
mesh.from_pydata(verts, [], faces)
---------------MAIN--------------------
#creation variables
headRadius = .1
tubeAcross = 2
tubeAround = 50
headAround = 50
tubeRadius = headRadius/2
arrows = bpy.data.collections.new("Arrows")
bpy.context.scene.collection.children.link(arrows)
numAcross = 5
v0 = Vector([-1, 1, 0])
v1 = Vector([-1, -1, 0])
v2 = Vector([1, 1, 0])
for i in range(numAcross):
for j in range(numAcross):
tip = v0 + (i/(numAcross - 1)) * (v2 - v0) + (j/(numAcross - 1)) * (v1 - v0)
arrowLength = tip.magnitude
headLength = sqrt(3 * headRadius**2)
tubeLength = arrowLength - headLength
createArrow(tubeRadius, arrowLength, headLength, tubeLength, tubeAcross, tubeAround, headAround, headRadius, arrows)
arrow = arrows.objects[j + i*numAcross]
for f in arrow.data.polygons:
f.use_smooth = True
arrow.data.use_auto_smooth = 1
arrow.data.auto_smooth_angle = radians(30)
x = tip.x
y = tip.y
z = tip.z
mag = sqrt(x**2 + y**2)
if x == 0 and y >= 0:
theta = pi/2
elif x == 0 and y < 0:
theta = -pi/2
elif x < 0:
theta = pi + atan(y/x)
else:
theta = atan(y/x)
if mag == 0 and z >= 0:
beta = pi/2
elif mag == 0 and z < 0:
beta = -pi/2
elif mag < 0:
beta = pi + atan(z/mag)
else:
beta = atan(z/mag)
arrow.rotation_euler = (0, beta, theta)
