"""BlenderCAM 'slice.py' © 2021 Alain Pelletier
Very simple slicing for 3D meshes, useful for plywood cutting.
Completely rewritten April 2021.
"""
import bpy
from bpy.props import (
BoolProperty,
FloatProperty,
)
from bpy.types import PropertyGroup
from . import (
constants,
utils,
)
[docs]
def slicing2d(ob, height):
"""Slice a 3D object at a specified height and convert it to a curve.
This function applies transformations to the given object, switches to
edit mode, selects all vertices, and performs a bisect operation to
slice the object at the specified height. After slicing, it resets the
object's location and applies transformations again before converting
the object to a curve. If the conversion fails (for instance, if the
mesh was empty), the function deletes the mesh and returns False.
Otherwise, it returns True.
Args:
ob (bpy.types.Object): The Blender object to be sliced and converted.
height (float): The height at which to slice the object.
Returns:
bool: True if the conversion to curve was successful, False otherwise.
"""
# April 2020 Alain Pelletier
# let's slice things
bpy.ops.object.transform_apply(location=True, rotation=False, scale=False)
bpy.ops.object.mode_set(mode='EDIT') # force edit mode
bpy.ops.mesh.select_all(action='SELECT') # select all vertices
# actual slicing here
bpy.ops.mesh.bisect(plane_co=(0.0, 0.0, height), plane_no=(0.0, 0.0, 1.0), use_fill=True, clear_inner=True,
clear_outer=True)
# slicing done
bpy.ops.object.mode_set(mode='OBJECT') # force object mode
# bring all the slices to 0 level and reset location transform
ob.location[2] = -1 * height
bpy.ops.object.transform_apply(location=True, rotation=False, scale=False)
bpy.ops.object.convert(target='CURVE') # convert it to curve
if bpy.context.active_object.type != 'CURVE': # conversion failed because mesh was empty so delete mesh
bpy.ops.object.delete(use_global=False, confirm=False)
return False
bpy.ops.object.select_all(action='DESELECT') # deselect everything
return True
[docs]
def slicing3d(ob, start, end):
"""Slice a 3D object along specified planes.
This function applies transformations to a given object and slices it in
the Z-axis between two specified values, `start` and `end`. It first
ensures that the object is in edit mode and selects all vertices before
performing the slicing operations using the `bisect` method. After
slicing, it resets the object's location and applies the transformations
to maintain the changes.
Args:
ob (Object): The 3D object to be sliced.
start (float): The starting Z-coordinate for the slice.
end (float): The ending Z-coordinate for the slice.
Returns:
bool: True if the slicing operation was successful.
"""
# April 2020 Alain Pelletier
# let's slice things
bpy.ops.object.transform_apply(location=True, rotation=False, scale=False)
bpy.ops.object.mode_set(mode='EDIT') # force edit mode
bpy.ops.mesh.select_all(action='SELECT') # select all vertices
# actual slicing here
bpy.ops.mesh.bisect(plane_co=(0.0, 0.0, start), plane_no=(0.0, 0.0, 1.0), use_fill=False, clear_inner=True,
clear_outer=False)
bpy.ops.mesh.select_all(action='SELECT') # select all vertices which
bpy.ops.mesh.bisect(plane_co=(0.0, 0.0, end), plane_no=(0.0, 0.0, 1.0), use_fill=True, clear_inner=False,
clear_outer=True)
# slicing done
bpy.ops.object.mode_set(mode='OBJECT') # force object mode
# bring all the slices to 0 level and reset location transform
ob.location[2] = -1 * start
bpy.ops.object.transform_apply(location=True, rotation=False, scale=False)
bpy.ops.object.select_all(action='DESELECT') # deselect everything
return True
[docs]
def sliceObject(ob):
"""Slice a 3D object into layers based on a specified thickness.
This function takes a 3D object and slices it into multiple layers
according to the specified thickness. It creates a new collection for
the slices and optionally creates text labels for each slice if the
indexes parameter is set. The slicing can be done in either 2D or 3D
based on the user's selection. The function also handles the positioning
of the slices based on the object's bounding box.
Args:
ob (bpy.types.Object): The 3D object to be sliced.
"""
# April 2020 Alain Pelletier
# get variables from menu
thickness = bpy.context.scene.cam_slice.slice_distance
slice3d = bpy.context.scene.cam_slice.slice_3d
indexes = bpy.context.scene.cam_slice.indexes
above0 = bpy.context.scene.cam_slice.slice_above0
# setup the collections
scollection = bpy.data.collections.new("Slices")
bpy.context.scene.collection.children.link(scollection)
if indexes:
tcollection = bpy.data.collections.new("Text")
bpy.context.scene.collection.children.link(tcollection)
bpy.ops.object.mode_set(mode='OBJECT') # force object mode
minx, miny, minz, maxx, maxy, maxz = utils.getBoundsWorldspace([ob])
start_height = minz
if above0 and minz < 0:
start_height = 0
# calculate amount of layers needed
layeramt = 1 + int((maxz - start_height) // thickness)
for layer in range(layeramt):
height = round(layer * thickness, 6) # height of current layer
t = str(layer) + "-" + str(height * 1000)
slicename = "slice_" + t # name for the current slice
tslicename = "t_" + t # name for the current slice text
height += start_height
print(slicename)
ob.select_set(True) # select object to be sliced
bpy.context.view_layer.objects.active = ob # make object to be sliced active
bpy.ops.object.duplicate() # make a copy of object to be sliced
bpy.context.view_layer.objects.active.name = slicename # change the name of object
# attribute active object to obslice
obslice = bpy.context.view_layer.objects.active
scollection.objects.link(obslice) # link obslice to scollecton
if slice3d:
# slice 3d at desired height and stop at desired height
slicesuccess = slicing3d(obslice, height, height + thickness)
else:
# slice object at desired height
slicesuccess = slicing2d(obslice, height)
if indexes and slicesuccess:
# text objects
bpy.ops.object.text_add() # new text object
textob = bpy.context.active_object
textob.data.size = 0.006 # change size of object
textob.data.body = t # text content
textob.location = (0, 0, 0) # text location
textob.name = tslicename # change the name of object
bpy.ops.object.select_all(action='DESELECT') # deselect everything
tcollection.objects.link(textob) # add to text collection
textob.parent = obslice # make textob child of obslice
# select all slices
for obj in bpy.data.collections['Slices'].all_objects:
obj.select_set(True)
[docs]
class SliceObjectsSettings(PropertyGroup):
"""Stores All Data for Machines"""
[docs]
slice_distance: FloatProperty(
name="Slicing Distance",
description="Slices distance in z, should be most often "
"thickness of plywood sheet.",
min=0.001,
max=10,
default=0.005,
precision=constants.PRECISION,
unit="LENGTH",
)
[docs]
slice_above0: BoolProperty(
name="Slice Above 0",
description="only slice model above 0",
default=False,
)
[docs]
slice_3d: BoolProperty(
name="3D Slice",
description="For 3D carving",
default=False,
)
[docs]
indexes: BoolProperty(
name="Add Indexes",
description="Adds index text of layer + index",
default=True,
)
