在科幻题材的视觉表现中，常出现由六边形与五边形组成的盾状结构，象征防御护甲等效果。本文将讲解如何在UE5中构建这样的球体护盾。
一.六边形/五边形 球体制作
1.因为纯六边形构建的球体在数学上不可能，因此这类球体都是由六边形与五边形组合构建。对于它的建模，你可以用DCC软件各显神通，也可以5分钟vibe coding搞定。我们用AI生成maya内的python脚本以完成该模型建模。
python
# -*- coding: utf-8 -*-
import math
from collections import defaultdict
import maya.cmds as cmds
# =========================================================
# 纯 Python 手动实现向量数学工具（零第三方库依赖）
# =========================================================
def vec_len(v):
return math.sqrt(v[0]**2 + v[1]**2 + v[2]**2)
def normalize(v):
length = vec_len(v)
if length > 0:
return [v[0] / length, v[1] / length, v[2] / length]
return v
def vec_dot(v1, v2):
return v1[0]*v2[0] + v1[1]*v2[1] + v1[2]*v2[2]
def vec_cross(v1, v2):
return [
v1[1]*v2[2] - v1[2]*v2[1],
v1[2]*v2[0] - v1[0]*v2[2],
v1[0]*v2[1] - v1[1]*v2[0]
]
def vec_sub(v1, v2):
return [v1[0] - v2[0], v1[1] - v2[1], v1[2] - v2[2]]
def poly_center(poly):
num_verts = len(poly)
return [
sum(v[0] for v in poly) / num_verts,
sum(v[1] for v in poly) / num_verts,
sum(v[2] for v in poly) / num_verts
]
# =========================================================
# 几何生成核心（二十面体对偶转换算法）
# =========================================================
def create_icosahedron(radius=1.0):
t = (1.0 + math.sqrt(5.0)) / 2.0
raw_verts = [
[-1, t, 0], [ 1, t, 0], [-1, -t, 0], [ 1, -t, 0],
[ 0, -1, t], [ 0, 1, t], [ 0, -1, -t], [ 0, 1, -t],
[ t, 0, -1], [ t, 0, 1], [-t, 0, -1], [-t, 0, 1]
]
verts = [ [component * radius for component in normalize(v)] for v in raw_verts ]
faces = [
[0,11,5], [0,5,1], [0,1,7], [0,7,10], [0,10,11],
[1,5,9], [5,11,4], [11,10,2], [10,7,6], [7,1,8],
[3,9,4], [3,4,2], [3,2,6], [3,6,8], [3,8,9],
[4,9,5], [2,4,11], [6,2,10], [8,6,7], [9,8,1]
]
return verts, faces
def subdivide(verts, faces, level=1, radius=1.0):
for _ in range(level):
midpoint_cache = {}
new_faces = []
def get_midpoint(i1, i2):
key = tuple(sorted((i1, i2)))
if key in midpoint_cache:
return midpoint_cache[key]
v1, v2 = verts[i1], verts[i2]
vm_raw = [(v1[0] + v2[0]) * 0.5, (v1[1] + v2[1]) * 0.5, (v1[2] + v2[2]) * 0.5]
vm = [component * radius for component in normalize(vm_raw)]
verts.append(vm)
idx = len(verts) - 1
midpoint_cache[key] = idx
return idx
for tri in faces:
a, b, c = tri
ab = get_midpoint(a, b)
bc = get_midpoint(b, c)
ca = get_midpoint(c, a)
new_faces.extend([[a, ab, ca], [b, bc, ab], [c, ca, bc], [ab, bc, ca]])
faces = new_faces
return verts, faces
def create_dual_mesh(verts, faces, radius=1.0):
face_centers = []
for f in faces:
raw_center = [
(verts[f[0]][0] + verts[f[1]][0] + verts[f[2]][0]) / 3.0,
(verts[f[0]][1] + verts[f[1]][1] + verts[f[2]][1]) / 3.0,
(verts[f[0]][2] + verts[f[1]][2] + verts[f[2]][2]) / 3.0
]
center = [component * radius for component in normalize(raw_center)]
face_centers.append(center)
vertex_faces = defaultdict(list)
for fi, face in enumerate(faces):
for v in face:
vertex_faces[v].append(fi)
polygons = []
for vi, connected_faces in vertex_faces.items():
center = verts[vi]
normal = normalize(center)
tangent = [1.0, 0.0, 0.0]
if abs(vec_dot(tangent, normal)) > 0.9:
tangent = [0.0, 1.0, 0.0]
tangent = normalize(vec_cross(normal, tangent))
bitangent = normalize(vec_cross(normal, tangent))
angles = []
for fi in connected_faces:
p = face_centers[fi]
d = vec_sub(p, center)
x = vec_dot(d, tangent)
y = vec_dot(d, bitangent)
angles.append((math.atan2(y, x), fi))
angles.sort()
polygons.append([face_centers[fi] for _, fi in angles])
return polygons
# =========================================================
# Maya 资产生成（对调通道色彩映射版）
# =========================================================
def build_honeycomb_mesh_in_maya(mesh_name, polygons, scale=100.0):
if cmds.objExists(mesh_name):
cmds.delete(mesh_name)
created_facets = []
pentagons = 0
hexagons = 0
# 暂时关闭撤销队列以提高拼装效率
cmds.undoInfo(stateWithoutFlush=False)
try:
for poly in polygons:
num_verts = len(poly)
if num_verts == 5: pentagons += 1
elif num_verts == 6: hexagons += 1
# 计算该单元网格的中心点与单位方向
center = poly_center(poly)
normal = normalize(center)
# 1. 新的 R 通道映射：基于 XZ 平面的方位角（经度），环绕一圈是 0-1
angle = math.atan2(normal[2], normal[0])
r_color = (angle + math.pi) / (2.0 * math.pi)
r_color = max(0.0, min(1.0, r_color))
# 2. 新的 G 通道映射：基于 Y 轴高度进行归一化映射 [-1, 1] -> [0, 1]
g_color = normal[1] * 0.5 + 0.5
g_color = max(0.0, min(1.0, g_color))
# 拼装单元格片面顶点的世界坐标
pts = [(v[0] * scale, v[1] * scale, v[2] * scale) for v in poly]
facet = cmds.polyCreateFacet(point=pts, ch=False)[0]
created_facets.append(facet)
# 写入对调后的颜色数据
cmds.polyColorPerVertex(facet, rgb=(r_color, g_color, 0.0), cdo=True)
# 1. 执行网格大融拼
combined_mesh = cmds.polyUnite(created_facets, ch=True, name=mesh_name)[0]
# 2. 规范化颜色集命名
current_sets = cmds.polyColorSet(combined_mesh, q=True, allColorSets=True)
if current_sets:
cmds.polyColorSet(combined_mesh, edit=True, colorSet=current_sets[0], newColorSet='colorSet1')
# 3. 固化历史
cmds.delete(combined_mesh, ch=True)
# 4. 视口外观设置
cmds.polySoftEdge(combined_mesh, angle=0, ch=False) # 全硬边保持结构
cmds.toggle(combined_mesh, vertexColor=True) # 开启视口顶点色数据显示
cmds.select(combined_mesh)
print("======================================================")
print(" Channel Swapped! Maya Honeycomb Mesh Re-generated. ")
print("======================================================")
print(f"Object Name : {combined_mesh}")
print(f"Color Set : colorSet1 (R: Circumference, G: Vertical)")
print(f"Total Cells : {len(polygons)}")
print("======================================================")
finally:
# 恢复撤销队列设置
cmds.undoInfo(stateWithoutFlush=True)
# =========================================================
# 执行主入口
# =========================================================
if __name__ == "__main__":
RADIUS = 1.0
SUBDIVISION = 3
SCALE_FACTOR = 100.0
MESH_NAME = "SM_ShieldSphere_Honeycomb"
print("Executing channel-swapped geometry generation pipeline...")
verts, faces = create_icosahedron(RADIUS)
verts, faces = subdivide(verts, faces, level=SUBDIVISION, radius=RADIUS)
polygons = create_dual_mesh(verts, faces, RADIUS)
build_honeycomb_mesh_in_maya(MESH_NAME, polygons, scale=SCALE_FACTOR)跑完之后效果长这样：
这个脚本用顶点色记录数据，每个cell是独立单元------R通道是绕周长映射的[0-1]区间，G通道是从下到上的映射，跟球面坐标那套逻辑一样。
2.但该球体无厚度，后序制作效果时会非常单薄，在MAYA中使用挤出命令设置厚度。
设置好后导出至到UE即可。
二.导入UE
3.导入UE后检查顶点色导入是否设置，如果未设置将该选项设置为Replace，点击Reimport Base Mesh重新导入。
4.选择Show - Vert Color预览顶点色。
5.加几个简单节点测试下，你会发现沿着法线做正弦运动时，效果一片混乱。
6.问题是因为挤出时法线并不一致，侧面的法线与正面法线朝向不同方向导致。但即使通过法线映射为一致，光照也会出现问题。
7.换个思路，之前在顶点色上缓存了球面坐标信息，可通过球面坐标反求法线。
Matrix Remap为方便使用的隐藏节点，需要通过复制粘贴命令得到：
cpp
Begin Object Class=/Script/UnrealEd.MaterialGraphNode Name="MaterialGraphNode_0"
Begin Object Class=/Script/InterchangeImport.MaterialExpressionRemap Name="MaterialExpressionRemap_0"
End Object
MaterialExpression=/Script/InterchangeImport.MaterialExpressionRemap'"MaterialExpressionRemap_0"'之所以要进行Remap值域转换，是因为UE对sin,cos进行了值域的修改，最终CellNormal为输出法线。
8.测试下效果。
9.最后根据你的需求继续完成制作。
