def remove_undercuts(context,
ob,
view,
world=True,
smooth=True,
epsilon=.000001):
'''
args:
ob - mesh object
view - Mathutils Vector
return:
Bmesh with Undercuts Removed?
best to make sure normals are consistent beforehand
best for manifold meshes, however non-man works
noisy meshes can be compensated for with island threhold
'''
#careful, this can get expensive with multires
me = ob.to_mesh(context.scene, True, 'RENDER')
bme = bmesh.new()
bme.from_mesh(me)
bme.normal_update()
bme.verts.ensure_lookup_table()
bme.edges.ensure_lookup_table()
bme.faces.ensure_lookup_table()
bvh = BVHTree.FromBMesh(bme)
#keep track of the world matrix
mx = ob.matrix_world
if world:
#meaning the vector is in world coords
#we need to take it back into local
i_mx = mx.inverted()
view = i_mx.to_quaternion() * view
face_directions = [[0]] * len(bme.faces)
up_faces = set()
overhang_faces = set() #all faces pointing away from view
#precalc all the face directions and store in dict
for f in bme.faces:
direction = f.normal.dot(view)
if direction <= -epsilon:
overhang_faces.add(f)
else:
up_faces.add(f)
face_directions[f.index] = direction
print('there are %i up_faces' % len(up_faces))
print('there are %i down_faces' % len(overhang_faces))
#for f in bme.faces:
# if f in overhangs:
# f.select_set(True)
# else:
# f.select_set(False)
overhang_islands = [
] #islands bigger than a certain threshold (by surface area?
upfacing_islands = []
def face_neighbors_up(bmface):
neighbors = []
for ed in bmface.edges:
neighbors += [
f for f in ed.link_faces if f != bmface and f in up_faces
]
return neighbors
#remove smal islands from up_faces and add to overhangs
max_iters = len(up_faces)
iters_0 = 0
islands_removed = 0
up_faces_copy = up_faces.copy()
while len(up_faces_copy) and iters_0 < max_iters:
iters_0 += 1
max_iters_1 = len(up_faces)
seed = up_faces_copy.pop()
new_faces = set(face_neighbors_up(seed))
up_faces_copy -= new_faces
island = set([seed])
island |= new_faces
iters_1 = 0
while iters_1 < max_iters_1 and new_faces:
iters_1 += 1
new_candidates = set()
for f in new_faces:
new_candidates.update(face_neighbors_up(f))
new_faces = new_candidates - island
if new_faces:
island |= new_faces
up_faces_copy -= new_faces
if len(
island
) < 75: #small patch surrounded by overhang, add to overhang area
islands_removed += 1
overhang_faces |= island
else:
upfacing_islands += [island]
print('%i upfacing islands removed' % islands_removed)
print('there are now %i down faces' % len(overhang_faces))
def face_neighbors_down(bmface):
neighbors = []
for ed in bmface.edges:
neighbors += [
f for f in ed.link_faces if f != bmface and f in overhang_faces
]
return neighbors
overhang_faces_copy = overhang_faces.copy()
while len(overhang_faces_copy):
seed = overhang_faces_copy.pop()
new_faces = set(face_neighbors_down(seed))
island = set([seed])
island |= new_faces
overhang_faces_copy -= new_faces
iters = 0
while iters < 100000 and new_faces:
iters += 1
new_candidates = set()
for f in new_faces:
new_candidates.update(face_neighbors_down(f))
new_faces = new_candidates - island
if new_faces:
island |= new_faces
overhang_faces_copy -= new_faces
if len(
island
) > 75: #TODO, calc overhang factor. Surface area dotted with direction
overhang_islands += [island]
for f in bme.faces:
f.select_set(False)
for ed in bme.edges:
ed.select_set(False)
for v in bme.verts:
v.select_set(False)
island_loops = []
island_verts = []
del_faces = set()
for isl in overhang_islands:
loop_eds = []
loop_verts = []
del_faces |= isl
for f in isl:
for ed in f.edges:
if len(ed.link_faces) == 1:
loop_eds += [ed]
loop_verts += [ed.verts[0], ed.verts[1]]
elif (ed.link_faces[0] in isl) and (ed.link_faces[1]
not in isl):
loop_eds += [ed]
loop_verts += [ed.verts[0], ed.verts[1]]
elif (ed.link_faces[1] in isl) and (ed.link_faces[0]
not in isl):
loop_eds += [ed]
loop_verts += [ed.verts[0], ed.verts[1]]
#f.select_set(True)
island_verts += [list(set(loop_verts))]
island_loops += [loop_eds]
bme.faces.ensure_lookup_table()
bme.edges.ensure_lookup_table()
loop_edges = []
for ed_loop in island_loops:
loop_edges += ed_loop
for ed in ed_loop:
ed.select_set(True)
loops_tools.relax_loops_util(bme, loop_edges, 5)
for ed in bme.edges:
ed.select_set(False)
exclude_vs = set()
for vs in island_verts:
exclude_vs.update(vs)
smooth_verts = []
for v in exclude_vs:
smooth_verts += [
ed.other_vert(v) for ed in v.link_edges
if ed.other_vert(v) not in exclude_vs
]
ret = bmesh.ops.extrude_edge_only(bme, edges=loop_edges)
new_fs = [
ele for ele in ret['geom'] if isinstance(ele, bmesh.types.BMFace)
]
new_vs = [
ele for ele in ret['geom'] if isinstance(ele, bmesh.types.BMVert)
]
#TODO, ray cast down to base plane?
for v in new_vs:
v.co -= 10 * view
for f in new_fs:
f.select_set(True)
bmesh.ops.delete(bme, geom=list(del_faces), context=3)
del_verts = []
for v in bme.verts:
if all([f in del_faces for f in v.link_faces]):
del_verts += [v]
bmesh.ops.delete(bme, geom=del_verts, context=1)
del_edges = []
for ed in bme.edges:
if len(ed.link_faces) == 0:
del_edges += [ed]
print('deleting %i edges' % len(del_edges))
bmesh.ops.delete(bme, geom=del_edges, context=4)
bmesh.ops.recalc_face_normals(bme, faces=new_fs)
bme.normal_update()
new_me = bpy.data.meshes.new(ob.name + '_blockout')
obj = bpy.data.objects.new(new_me.name, new_me)
context.scene.objects.link(obj)
obj.select = True
context.scene.objects.active = obj
bme.to_mesh(obj.data)
# Get material
mat = bpy.data.materials.get("Model Material")
if mat is None:
# create material
print('creating model material')
mat = bpy.data.materials.new(name="Model Material")
#mat.diffuse_color = Color((0.8, .8, .8))
# Assign it to object
obj.data.materials.append(mat)
print('Model material added')
mat2 = bpy.data.materials.get("Undercut Material")
if mat2 is None:
# create material
mat2 = bpy.data.materials.new(name="Undercut Material")
mat2.diffuse_color = Color((0.8, .2, .2))
obj.data.materials.append(mat2)
mat_ind = obj.data.materials.find("Undercut Material")
print('Undercut material is %i' % mat_ind)
for f in new_faces:
obj.data.polygons[f.index].material_index = mat_ind
if world:
obj.matrix_world = mx
bme.free()
del bvh
return
def remove_undercuts(context, ob, view, world = True, smooth = True, epsilon = .000001):
'''
args:
ob - mesh object
view - Mathutils Vector
return:
Bmesh with Undercuts Removed?
best to make sure normals are consistent beforehand
best for manifold meshes, however non-man works
noisy meshes can be compensated for with island threhold
'''
#careful, this can get expensive with multires
me = ob.to_mesh(context.scene, True, 'RENDER')
bme = bmesh.new()
bme.from_mesh(me)
bme.normal_update()
bme.verts.ensure_lookup_table()
bme.edges.ensure_lookup_table()
bme.faces.ensure_lookup_table()
bvh = BVHTree.FromBMesh(bme)
#keep track of the world matrix
mx = ob.matrix_world
if world:
#meaning the vector is in world coords
#we need to take it back into local
i_mx = mx.inverted()
view = i_mx.to_quaternion() * view
face_directions = [[0]] * len(bme.faces)
up_faces = set()
overhang_faces = set() #all faces pointing away from view
#precalc all the face directions and store in dict
for f in bme.faces:
direction = f.normal.dot(view)
if direction <= -epsilon:
overhang_faces.add(f)
else:
up_faces.add(f)
face_directions[f.index] = direction
print('there are %i up_faces' % len(up_faces))
print('there are %i down_faces' % len(overhang_faces))
#for f in bme.faces:
# if f in overhangs:
# f.select_set(True)
# else:
# f.select_set(False)
overhang_islands = [] #islands bigger than a certain threshold (by surface area?
upfacing_islands = []
def face_neighbors_up(bmface):
neighbors = []
for ed in bmface.edges:
neighbors += [f for f in ed.link_faces if f != bmface and f in up_faces]
return neighbors
#remove smal islands from up_faces and add to overhangs
max_iters = len(up_faces)
iters_0 = 0
islands_removed = 0
up_faces_copy = up_faces.copy()
while len(up_faces_copy) and iters_0 < max_iters:
iters_0 += 1
max_iters_1 = len(up_faces)
seed = up_faces_copy.pop()
new_faces = set(face_neighbors_up(seed))
up_faces_copy -= new_faces
island = set([seed])
island |= new_faces
iters_1 = 0
while iters_1 < max_iters_1 and new_faces:
iters_1 += 1
new_candidates = set()
for f in new_faces:
new_candidates.update(face_neighbors_up(f))
new_faces = new_candidates - island
if new_faces:
island |= new_faces
up_faces_copy -= new_faces
if len(island) < 75: #small patch surrounded by overhang, add to overhang area
islands_removed += 1
overhang_faces |= island
else:
upfacing_islands += [island]
print('%i upfacing islands removed' % islands_removed)
print('there are now %i down faces' % len(overhang_faces))
def face_neighbors_down(bmface):
neighbors = []
for ed in bmface.edges:
neighbors += [f for f in ed.link_faces if f != bmface and f in overhang_faces]
return neighbors
overhang_faces_copy = overhang_faces.copy()
while len(overhang_faces_copy):
seed = overhang_faces_copy.pop()
new_faces = set(face_neighbors_down(seed))
island = set([seed])
island |= new_faces
overhang_faces_copy -= new_faces
iters = 0
while iters < 100000 and new_faces:
iters += 1
new_candidates = set()
for f in new_faces:
new_candidates.update(face_neighbors_down(f))
new_faces = new_candidates - island
if new_faces:
island |= new_faces
overhang_faces_copy -= new_faces
if len(island) > 75: #TODO, calc overhang factor. Surface area dotted with direction
overhang_islands += [island]
for f in bme.faces:
f.select_set(False)
for ed in bme.edges:
ed.select_set(False)
for v in bme.verts:
v.select_set(False)
island_loops = []
island_verts = []
del_faces = set()
for isl in overhang_islands:
loop_eds = []
loop_verts = []
del_faces |= isl
for f in isl:
for ed in f.edges:
if len(ed.link_faces) == 1:
loop_eds += [ed]
loop_verts += [ed.verts[0], ed.verts[1]]
elif (ed.link_faces[0] in isl) and (ed.link_faces[1] not in isl):
loop_eds += [ed]
loop_verts += [ed.verts[0], ed.verts[1]]
elif (ed.link_faces[1] in isl) and (ed.link_faces[0] not in isl):
loop_eds += [ed]
loop_verts += [ed.verts[0], ed.verts[1]]
#f.select_set(True)
island_verts += [list(set(loop_verts))]
island_loops += [loop_eds]
bme.faces.ensure_lookup_table()
bme.edges.ensure_lookup_table()
loop_edges = []
for ed_loop in island_loops:
loop_edges += ed_loop
for ed in ed_loop:
ed.select_set(True)
loops_tools.relax_loops_util(bme, loop_edges, 5)
for ed in bme.edges:
ed.select_set(False)
exclude_vs = set()
for vs in island_verts:
exclude_vs.update(vs)
smooth_verts = []
for v in exclude_vs:
smooth_verts += [ed.other_vert(v) for ed in v.link_edges if ed.other_vert(v) not in exclude_vs]
ret = bmesh.ops.extrude_edge_only(bme, edges = loop_edges)
new_fs = [ele for ele in ret['geom'] if isinstance(ele, bmesh.types.BMFace)]
new_vs = [ele for ele in ret['geom'] if isinstance(ele, bmesh.types.BMVert)]
#TODO, ray cast down to base plane?
for v in new_vs:
v.co -= 10*view
for f in new_fs:
f.select_set(True)
bmesh.ops.delete(bme, geom = list(del_faces), context = 3)
del_verts = []
for v in bme.verts:
if all([f in del_faces for f in v.link_faces]):
del_verts += [v]
bmesh.ops.delete(bme, geom = del_verts, context = 1)
del_edges = []
for ed in bme.edges:
if len(ed.link_faces) == 0:
del_edges += [ed]
print('deleting %i edges' % len(del_edges))
bmesh.ops.delete(bme, geom = del_edges, context = 4)
bmesh.ops.recalc_face_normals(bme, faces = new_fs)
bme.normal_update()
new_me = bpy.data.meshes.new(ob.name + '_blockout')
obj = bpy.data.objects.new(new_me.name, new_me)
context.scene.objects.link(obj)
obj.select = True
context.scene.objects.active = obj
bme.to_mesh(obj.data)
# Get material
mat = bpy.data.materials.get("Model Material")
if mat is None:
# create material
print('creating model material')
mat = bpy.data.materials.new(name="Model Material")
#mat.diffuse_color = Color((0.8, .8, .8))
# Assign it to object
obj.data.materials.append(mat)
print('Model material added')
mat2 = bpy.data.materials.get("Undercut Material")
if mat2 is None:
# create material
mat2 = bpy.data.materials.new(name="Undercut Material")
mat2.diffuse_color = Color((0.8, .2, .2))
obj.data.materials.append(mat2)
mat_ind = obj.data.materials.find("Undercut Material")
print('Undercut material is %i' % mat_ind)
for f in new_faces:
obj.data.polygons[f.index].material_index = mat_ind
if world:
obj.matrix_world = mx
bme.free()
del bvh
return