Slicing script based on Bisect

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1

Hello,

I am trying to do a slicing script based on mesh bisect that will cut me any object, say in the z direction in x slices of a certain thickness and preserve the original object.

Right now, I am just trying the basics in a simple script but can not get two bisect operations to work after each other.
This script works with the default cube selected from the default scene and should have resulted right now in slicing a 0.1 unit piece from z=0 to z=0.1

the first bisect works, the second does not

Why can I not do two bisect after each other ? Tried to use bpy.ops.mesh.select_all() to select all vertices but that does not help.

Help appreciated.

import bpy
    
def duplicateObject(scene, name, copyobj):
 
    # Create new mesh
    mesh = bpy.data.meshes.new(name)
 
    # Create new object associated with the mesh
    ob_new = bpy.data.objects.new(name, mesh)
 
    # Copy data block from the old object into the new object
    ob_new.data = copyobj.data.copy()
    ob_new.scale = copyobj.scale
    ob_new.location = copyobj.location
 
    # Link new object to the given scene and select it
    scene.objects.link(ob_new)
    ob_new.select = True
 
    return ob_new
    
print()
print ("Script start")


thickness=0.1
slices=3


scene = bpy.context.scene


# Note sur bound_box for v in bpy.data.objects["Cube"].bound_box    
activeObjects=bpy.context.selected_objects


for activeObject in activeObjects:
    for slicenr in range(0,1):
        slicename="slice"+str(slicenr)
        print("Now doing slice "+slicename)
        cobj=duplicateObject(scene,slicename,activeObject)
    
        #bpy.ops.object.select_all(action='DESELECT')
        #bpy.ops.object.select_pattern(pattern="slice0")
        bpy.context.scene.objects.active = bpy.data.objects[slicename]
        bpy.ops.object.mode_set(mode='EDIT')
        bpy.ops.mesh.bisect(plane_co=(0,0,0),plane_no=(0,0,1),xstart=0,xend=100,ystart=0,yend=100,clear_outer=False,clear_inner=True)
        bpy.ops.object.mode_set(mode='OBJECT')
        bpy.ops.object.mode_set(mode='EDIT')
        bpy.ops.mesh.select_all()
        print(thickness*(1+slicenr))
        bpy.ops.mesh.bisect(plane_co=(0,0,0+thickness*(1+slicenr)),plane_no=(0,0,1),xstart=0,xend=100,ystart=0,yend=100,clear_outer=True,clear_inner=False)
2

Does this help?

http://www.blenderartists.org/forum/showthread.php?311073-Automatic-divide-mesh-in-tiles&p=2479783&viewfull=1#post2479783

3

Thanks, just seen your post and solved the issue meanwhile, I was missing a proper select all vertices (was doing a toggle action by default instead of a select)

The working code is below :

for activeObject in activeObjects:
for slicenr in range(0,1):
slicename=“slice”+str(slicenr)
print("Now doing slice "+slicename)
cobj=duplicateObject(scene,slicename,activeObject)
bpy.ops.object.select_all(action=‘DESELECT’)
bpy.context.scene.objects.active = bpy.data.objects[slicename]
bpy.ops.object.mode_set(mode=‘EDIT’)
bpy.ops.mesh.select_all(action=‘SELECT’)
bpy.ops.mesh.bisect(plane_co=(0,0,0),plane_no=(0,0,1),clear_outer=False,clear_inner=True)
bpy.ops.mesh.select_all(action=‘SELECT’)
print(thickness*(1+slicenr))
bpy.ops.mesh.bisect(plane_co=(0,0,thickness*(1+slicenr)),plane_no=(0,0,1),clear_outer=True,clear_inner=False)
bpy.ops.object.mode_set(mode=‘OBJECT’)