Model one half and this modifier flips a copy onto the other side — the usual starting point for symmetric models.
Also known as: Mirrormodifiers.new(type='MIRROR')
···
bpy — this entry
# 왼쪽 반만 만들고 미러 모디파이어로 오른쪽을 채운다.
import bmesh
reset('WORKBENCH')
camera((0, -8, 4.5), target=(0, 0, 1.0))
floor()
bpy.ops.mesh.primitive_cube_add(size=1.2, location=(0, 0, 1.0))
half = bpy.context.object
half.name = 'Half'
bm = bmesh.new()
bm.from_mesh(half.data)
bmesh.ops.subdivide_edges(bm, edges=bm.edges[:], cuts=3, use_grid_fill=True)
# x > 0 쪽 꼭짓점을 지워 왼쪽 절반만 남긴다(가운데 x = 0 줄은 남는다)
bmesh.ops.delete(bm, geom=[v for v in bm.verts if v.co.x > 0.001], context='VERTS')
for v in bm.verts: # 왼쪽 위를 날개처럼 끌어낸다
if v.co.x < -0.5 and v.co.z > 0:
v.co.x -= 0.7
v.co.z += 0.35
bm.to_mesh(half.data)
bm.free()
mirror = half.modifiers.new('Mirror', 'MIRROR')
mirror.use_axis = (True, False, False) # 오브젝트 원점의 X 축을 기준으로 뒤집어 붙인다
mirror.use_clip = True # 편집할 때 가운데 꼭짓점이 반대편으로 넘어가지 않게
mirror.use_mirror_merge = True # 가운데 겹친 꼭짓점을 하나로 합친다
subsurf = half.modifiers.new('Subdivision', 'SUBSURF')
subsurf.levels = subsurf.render_levels = 2
frame(half, margin=1.6) # 미러까지 켠 완성 모양에 맞춰 카메라를 둔다
for mod in half.modifiers: # 렌더에서만 잠시 끈다 — 모디파이어는 그대로 남아 있다
mod.show_render = False
paint(half, material('Clay', CLAY))
shoot('off')
for mod in half.modifiers:
mod.show_render = True
paint(half, material('Lime', LIME))
shoot('on')
Full script — runs as-is in Blender 5.1.1
# mirror-modifier — Blender 5.1.1 에서 그대로 돌아가는 스크립트
# 실행: blender -b --factory-startup --python mirror-modifier.py -- <출력 폴더>
SLUG = 'mirror-modifier'
# ── 무대: 모든 항목이 같이 쓰는 준비 코드 (renders/_stage.py) ──────────────────
# 빈 장면 → 렌더 엔진·크기 → 카메라·바닥·조명·재질 도우미 → shoot() 으로 WebP 저장.
import bpy, math, os, sys
from mathutils import Vector
# 출력 폴더: blender -b --factory-startup --python 이파일.py -- <출력 폴더>
OUT = sys.argv[sys.argv.index('--') + 1] if '--' in sys.argv[:-1] else os.getcwd()
os.makedirs(OUT, exist_ok=True)
# 색은 화면에서 고르는 sRGB 0~1 값으로 적는다. 블렌더 내부는 선형(linear)이라 srgb() 로 바꿔 넣는다.
BACKDROP = (0.24, 0.25, 0.27)
CLAY = (0.80, 0.77, 0.72)
LIME = (0.64, 0.90, 0.21)
SKY = (0.22, 0.65, 0.95)
CORAL = (0.96, 0.42, 0.45)
INK = (0.08, 0.09, 0.10)
ENGINES = {'WORKBENCH': 'BLENDER_WORKBENCH', 'EEVEE': 'BLENDER_EEVEE', 'CYCLES': 'CYCLES'}
def srgb(c, alpha=1.0):
lin = lambda v: v / 12.92 if v <= 0.04045 else ((v + 0.055) / 1.055) ** 2.4
return (lin(c[0]), lin(c[1]), lin(c[2]), alpha)
def reset(engine='WORKBENCH', samples=16, size=(960, 600)):
"""빈 장면에서 시작한다. engine: WORKBENCH(모양 확인) · EEVEE(실시간) · CYCLES(경로 추적)."""
bpy.ops.wm.read_factory_settings(use_empty=True)
sc = bpy.context.scene
sc.render.engine = ENGINES[engine]
sc.render.resolution_x, sc.render.resolution_y = size
sc.render.resolution_percentage = 100
sc.render.image_settings.file_format = 'WEBP'
sc.render.image_settings.quality = 82
sc.world = bpy.data.worlds.new('World')
world_color(BACKDROP)
if engine == 'WORKBENCH':
sh = sc.display.shading
sh.light, sh.color_type = 'STUDIO', 'MATERIAL'
sh.show_shadows, sh.shadow_intensity = True, 0.35
sh.show_cavity = True
sc.display.render_aa = '16'
sc.view_settings.view_transform = 'Standard' # 재질 색을 그대로 보여 준다
elif engine == 'EEVEE':
sc.eevee.taa_render_samples = samples
else:
sc.cycles.samples = samples
sc.cycles.use_denoising = True
return sc
def world_color(color, strength=1.0):
"""배경색. Workbench 는 world.color, EEVEE·Cycles 는 Background 노드를 쓴다."""
w = bpy.context.scene.world
w.color = srgb(color)[:3]
bg = w.node_tree.nodes.get('Background') if w.node_tree else None
if bg:
bg.inputs['Color'].default_value = srgb(color)
bg.inputs['Strength'].default_value = strength
return w
def hdri(name='studio', strength=1.0, show=False):
"""블렌더에 들어 있는 HDRI 로 장면을 비춘다(CC0 · Poly Haven). name: studio · city · courtyard · forest · interior · night · sunrise · sunset.
show=False 면 빛과 반사에만 쓰고, 카메라에는 BACKDROP 색 배경이 보인다(Light Path 의 Is Camera Ray 로 가른다)."""
nt = bpy.context.scene.world.node_tree
nodes, links = nt.nodes, nt.links
env = nodes.new('ShaderNodeTexEnvironment')
env.image = bpy.data.images.load(os.path.join(bpy.utils.system_resource('DATAFILES'), 'studiolights', 'world', f'{name}.exr'))
bg = nodes['Background']
bg.inputs['Strength'].default_value = strength
links.new(env.outputs['Color'], bg.inputs['Color'])
if not show:
flat = nodes.new('ShaderNodeBackground')
flat.inputs['Color'].default_value = srgb(BACKDROP)
ray, mix = nodes.new('ShaderNodeLightPath'), nodes.new('ShaderNodeMixShader')
links.new(ray.outputs['Is Camera Ray'], mix.inputs['Fac'])
links.new(bg.outputs['Background'], mix.inputs[1])
links.new(flat.outputs['Background'], mix.inputs[2])
links.new(mix.outputs['Shader'], nodes['World Output'].inputs['Surface'])
return env
def look_at(obj, target):
obj.rotation_euler = (Vector(target) - obj.location).to_track_quat('-Z', 'Y').to_euler()
def camera(location=(7, -7, 5), target=(0, 0, 0.5), lens=50):
cam = bpy.data.objects.new('Camera', bpy.data.cameras.new('Camera'))
bpy.context.scene.collection.objects.link(cam)
cam.location = location
look_at(cam, target)
cam.data.lens = lens
bpy.context.scene.camera = cam
return cam
def frame(*objs, margin=1.15):
"""카메라 방향은 그대로 두고, objs 가 화면에 다 들어오게 카메라를 앞뒤로 옮긴다."""
sc = bpy.context.scene
dg = bpy.context.evaluated_depsgraph_get()
pts = [o.matrix_world @ Vector(c) for o in objs for c in o.evaluated_get(dg).bound_box]
mid = sum(pts, Vector()) / len(pts)
coords = [c for p in pts for c in (mid + (p - mid) * margin)]
loc, _scale = sc.camera.camera_fit_coords(dg, coords)
sc.camera.location = loc
return sc.camera
def light(kind='AREA', location=(4, -4, 6), target=(0, 0, 0), energy=600, size=3.0, color=(1, 1, 1)):
"""kind: POINT · SUN · SPOT · AREA. energy 는 와트(SUN 은 W/m²에 해당하는 세기)."""
data = bpy.data.lights.new(kind.title(), kind)
data.energy, data.color = energy, color
if kind == 'AREA':
data.size = size
obj = bpy.data.objects.new(data.name, data)
bpy.context.scene.collection.objects.link(obj)
obj.location = location
look_at(obj, target)
return obj
def studio(key=700, fill=200, rim=450):
"""기본 3점 조명(키·필·림). EEVEE·Cycles 용 — Workbench 는 자체 스튜디오 조명을 쓴다."""
return [light('AREA', (5, -4, 6), energy=key, size=4),
light('AREA', (-6, -3, 3), energy=fill, size=5),
light('AREA', (0, 6, 5), energy=rim, size=3)]
def material(name, color=CLAY, roughness=0.5, metallic=0.0, **inputs):
"""원리 BSDF 재질. inputs 는 소켓 이름(공백은 _ 로): Emission_Strength=3."""
mat = bpy.data.materials.new(name)
mat.diffuse_color = srgb(color) # Workbench 가 보는 색
bsdf = mat.node_tree.nodes['Principled BSDF']
bsdf.inputs['Base Color'].default_value = srgb(color)
bsdf.inputs['Roughness'].default_value = roughness
bsdf.inputs['Metallic'].default_value = metallic
for key, value in inputs.items():
bsdf.inputs[key.replace('_', ' ')].default_value = value
return mat
def paint(obj, mat):
obj.data.materials.clear()
obj.data.materials.append(mat)
return obj
def floor(size=80.0, color=None, z=0.0, wall=30.0, curve=6.0):
"""바닥과 뒷벽(+Y 쪽)이 둥글게 이어진 스튜디오 배경 — 지평선이 보이지 않는다. 카메라는 -Y 쪽에서 +Y 를 보게 둔다."""
import bmesh
back = size / 2
steps = 12
profile = [(-back, 0.0)] # (y, z) 단면: 앞 → 둥근 모서리 → 벽 위
for i in range(steps + 1):
a = (math.pi / 2) * i / steps
profile.append((back - curve + curve * math.sin(a), curve - curve * math.cos(a)))
profile.append((back, wall))
bm = bmesh.new()
left = [bm.verts.new((-back, y, z + h)) for y, h in profile]
right = [bm.verts.new((back, y, z + h)) for y, h in profile]
for i in range(len(profile) - 1):
bm.faces.new((left[i], right[i], right[i + 1], left[i + 1]))
me = bpy.data.meshes.new('Floor')
bm.to_mesh(me)
bm.free()
obj = bpy.data.objects.new('Floor', me)
bpy.context.scene.collection.objects.link(obj)
for poly in me.polygons:
poly.use_smooth = True
return paint(obj, material('Floor', color or BACKDROP, roughness=0.9))
def edges(obj, thickness=0.012, color=INK):
"""메시의 선(엣지)을 렌더에 보이게 한다 — 모디파이어까지 적용된 모양에 와이어프레임을 씌운 복제본."""
dg = bpy.context.evaluated_depsgraph_get()
wire = bpy.data.objects.new(obj.name + '.edges', bpy.data.meshes.new_from_object(obj.evaluated_get(dg)))
bpy.context.scene.collection.objects.link(wire)
wire.matrix_world = obj.matrix_world.copy()
mod = wire.modifiers.new('Wireframe', 'WIREFRAME')
mod.thickness, mod.use_even_offset = thickness, True
return paint(wire, material(obj.name + '.edges', color, roughness=0.8))
def shoot(name):
"""지금 장면을 <출력 폴더>/<항목>-<name>.webp 로 렌더한다."""
sc = bpy.context.scene
sc.render.filepath = os.path.join(OUT, f'{SLUG}-{name}.webp')
bpy.ops.render.render(write_still=True)
return sc.render.filepath
# ── 이 항목 ──
# 왼쪽 반만 만들고 미러 모디파이어로 오른쪽을 채운다.
import bmesh
reset('WORKBENCH')
camera((0, -8, 4.5), target=(0, 0, 1.0))
floor()
bpy.ops.mesh.primitive_cube_add(size=1.2, location=(0, 0, 1.0))
half = bpy.context.object
half.name = 'Half'
bm = bmesh.new()
bm.from_mesh(half.data)
bmesh.ops.subdivide_edges(bm, edges=bm.edges[:], cuts=3, use_grid_fill=True)
# x > 0 쪽 꼭짓점을 지워 왼쪽 절반만 남긴다(가운데 x = 0 줄은 남는다)
bmesh.ops.delete(bm, geom=[v for v in bm.verts if v.co.x > 0.001], context='VERTS')
for v in bm.verts: # 왼쪽 위를 날개처럼 끌어낸다
if v.co.x < -0.5 and v.co.z > 0:
v.co.x -= 0.7
v.co.z += 0.35
bm.to_mesh(half.data)
bm.free()
mirror = half.modifiers.new('Mirror', 'MIRROR')
mirror.use_axis = (True, False, False) # 오브젝트 원점의 X 축을 기준으로 뒤집어 붙인다
mirror.use_clip = True # 편집할 때 가운데 꼭짓점이 반대편으로 넘어가지 않게
mirror.use_mirror_merge = True # 가운데 겹친 꼭짓점을 하나로 합친다
subsurf = half.modifiers.new('Subdivision', 'SUBSURF')
subsurf.levels = subsurf.render_levels = 2
frame(half, margin=1.6) # 미러까지 켠 완성 모양에 맞춰 카메라를 둔다
for mod in half.modifiers: # 렌더에서만 잠시 끈다 — 모디파이어는 그대로 남아 있다
mod.show_render = False
paint(half, material('Clay', CLAY))
shoot('off')
for mod in half.modifiers:
mod.show_render = True
paint(half, material('Lime', LIME))
shoot('on')
Faces, cars and chairs are symmetric, so you only need to shape half. The Mirror modifier adds a flipped copy of that half across the object's origin — to the result only. The source mesh stays a half, so moving a vertex on one side updates the other live. In the UI it lives in the Properties editor ▸ wrench tab (Modifiers) ▸ Add Modifier ▸ Generate ▸ Mirror.
In code it is one line: obj.modifiers.new('Mirror', 'MIRROR'). use_axis picks which of X, Y, Z to flip across, use_clip stops center vertices from crossing to the other side while editing, and use_mirror_merge with merge_threshold welds the overlapping center vertices. To mirror across something other than the origin, set mirror_object to an empty or any object. To bake the result into real geometry, call bpy.ops.object.modifier_apply(modifier='Mirror').
The classic mistake is the origin. The flip happens across the object's own origin, not the world center, so if the origin is not on the seam the halves overlap or leave a gap. Put Subdivision Surface after Mirror, as in this example, and the seam smooths over; swap the order and a crease appears down the middle (modifiers evaluate top to bottom).
When to use
Turn it on as soon as you start any symmetric model. Apply it only when you reach asymmetric details such as scars or logos.