object_print3d_utils/__init__.py

@@ -122,22 +122,29 @@ class SceneProperties(PropertyGroup):
         max=math.radians(90.0),
     )
     hollow_offset: FloatProperty(
-        name = "Offset",
-        description = "Surface offset in relation to original mesh. Negative -> inwards",
-        default = -5.0,
-        subtype = 'DISTANCE',
+        name="Offset",
+        description="Surface offset in relation to original mesh",
+        default=1.0,
+        subtype='DISTANCE',
+        min=0.0,
+        step=1,
         )
-    hollow_resolution: FloatProperty(
-        name = "Resolution",
-        description = "Resolution of the voxel grid used for hollowing",
-        default = 5.0,
-        min = 0.01,
-        subtype = 'DISTANCE',
+    hollow_voxel_size: FloatProperty(
+        name="Voxel size",
+        description="Size of the voxel used for volume evaluation. Lower values preserve finer details",
+        default=1.0,
+        min=0.0001,
+        step=1,
+        subtype='DISTANCE',
         )
-    hollow_create: BoolProperty(
-        name = "Create Hollow Copy",
-        description = "Create a hollow copy of the target object, with applied modifiers and scale",
-        default = False
+    make_hollow_duplicate: BoolProperty(
+        name="Hollow Duplicate",
+        description="Create hollowed out copy of the object",
+        )
+    make_hollow_inside: BoolProperty(
+        name="Inside",
+        description="Offset surface inside of the object",
+        default=True,
         )
 
 
@@ -146,7 +153,7 @@ classes = (
 
     ui.VIEW3D_PT_print3d_analyze,
     ui.VIEW3D_PT_print3d_cleanup,
-    ui.VIEW3D_PT_print3d_transform,
+    ui.VIEW3D_PT_print3d_edit,
     ui.VIEW3D_PT_print3d_export,
 
     operators.MESH_OT_print3d_info_volume,

object_print3d_utils/operators.py

@@ -826,27 +826,34 @@ class MESH_OT_print3d_export(Operator):
 
 class MESH_OT_print3d_hollow(Operator):
     bl_idname = "mesh.print3d_hollow"
-    bl_label = "Create offset surface"
-    bl_description = "Create offset surface for hollowing objects"
+    bl_label = "Hollow"
+    bl_description = "Create offset surface"
     bl_options = {'REGISTER', 'UNDO'}
 
     offset: FloatProperty(
-        name = "Offset",
-        description = "Surface offset in relation to original mesh. Negative -> inwards",
-        default = -5.0,
-        subtype = 'DISTANCE',
+        name="Offset",
+        description="Surface offset in relation to original mesh",
+        default=1.0,
+        subtype='DISTANCE',
+        min=0.0,
+        step=1,
         )
-    resolution: FloatProperty(
-        name = "Resolution",
-        description = "Resolution of the voxel grid used for hollowing",
-        default = 5.0,
-        min = 0.01,
-        subtype = 'DISTANCE',
+    voxel_size: FloatProperty(
+        name="Voxel size",
+        description="Size of the voxel used for volume evaluation. Lower values preserve finer details",
+        default=5.0,
+        min=0.0001,
+        step=1,
+        subtype='DISTANCE',
         )
-    create_hollow: BoolProperty(
-        name = "Create Hollow Copy",
-        description = "Create a hollow copy of the target object, with applied modifiers and scale",
-        default = False
+    make_hollow_duplicate: BoolProperty(
+        name="Hollow Duplicate",
+        description="Create hollowed out copy of the object",
+        )
+    make_hollow_inside: BoolProperty(
+        name="Inside",
+        description="Offset surface inside of the object",
+        default=True,
         )
 
     def execute(self, context):
@@ -877,62 +884,64 @@ class MESH_OT_print3d_hollow(Operator):
         tris.shape = (-1, 3)
 
         # Generate VDB levelset
-        half_width = max(3.0, math.ceil(abs(self.offset) / self.resolution) + 2.0) # half_width has to envelop offset
+        half_width = max(3.0, math.ceil(abs(self.offset) / self.voxel_size) + 2.0) # half_width has to envelop offset
         trans = vdb.Transform()
-        trans.scale(self.resolution)
+        trans.scale(self.voxel_size)
         levelset = vdb.FloatGrid.createLevelSetFromPolygons(verts, triangles=tris, transform=trans, halfWidth=half_width)
 
         # Generate offset surface
+        if self.make_hollow_inside:
+            newverts, newquads = levelset.convertToQuads(-self.offset)
+        else:
             newverts, newquads = levelset.convertToQuads(self.offset)
+
         polys = list(newquads)
 
         # Instantiate new object in Blender
-        mesh_offset = bpy.data.meshes.new(mesh_target.name + ' offset')
-        mesh_offset.from_pydata(newverts, [], polys)
-        obj_offset = bpy.data.objects.new(obj.name + ' offset', mesh_offset)
-        bpy.context.collection.objects.link(obj_offset)
-
-        if not self.create_hollow:
-            # For some reason OpenVDB has inverted normals
-            mesh_offset.flip_normals()
-            # Translate surface object to target object's position
-            obj_offset.matrix_world.translation = obj.matrix_world.translation
-            # This mesh will not be used anymore
-            bpy.data.meshes.remove(mesh_target)
-        else:
-            # Create a copy of the target object with applied modifiers and scale
-            obj_hollow = bpy.data.objects.new(obj.name + " hollow", mesh_target)
-            bpy.context.collection.objects.link(obj_hollow)
-            if self.offset < 0.0:
-                # Offset surface already has normals as they should, see above
-                pass
-            else:
-                # Offset surface is outside, correct normals, see above
-                mesh_offset.flip_normals()
-                # Original surface is inside, flip its normals
-                mesh_target.flip_normals()
-            
         bpy.ops.object.mode_set(mode='OBJECT')
         bpy.ops.object.select_all(action='DESELECT')
+        mesh_offset = bpy.data.meshes.new(mesh_target.name + ' offset')
+        mesh_offset.from_pydata(newverts, [], polys)
+
+        # For some reason OpenVDB has inverted normals
+        mesh_offset.flip_normals()
+        obj_offset = bpy.data.objects.new(obj.name + ' offset', mesh_offset)
+        obj_offset.matrix_world.translation = obj.matrix_world.translation
+        bpy.context.collection.objects.link(obj_offset)
         obj_offset.select_set(True)
+        context.view_layer.objects.active = obj_offset
+
+        if self.make_hollow_duplicate:
+            obj_hollow = bpy.data.objects.new(obj.name + " hollow", mesh_target)
+            bpy.context.collection.objects.link(obj_hollow)
+            obj_hollow.matrix_world.translation = obj.matrix_world.translation
             obj_hollow.select_set(True)
+            if self.make_hollow_inside:
+                mesh_offset.flip_normals()
+            else:
+                mesh_target.flip_normals()
             context.view_layer.objects.active = obj_hollow
             bpy.ops.object.join()
+        else:
+            bpy.data.meshes.remove(mesh_target)
 
-            # Translate hollow object to target object's position
-            obj_hollow.matrix_world.translation = obj.matrix_world.translation
-
+        print_3d = context.scene.print_3d
+        print_3d.hollow_offset = self.offset
+        print_3d.hollow_voxel_size = self.voxel_size
+        print_3d.make_hollow_duplicate = self.make_hollow_duplicate
+        print_3d.make_hollow_inside = self.make_hollow_inside
 
         return {'FINISHED'}
 
     def invoke(self, context, event):
         print_3d = context.scene.print_3d
         self.offset = print_3d.hollow_offset
-        self.resolution = print_3d.hollow_resolution
-        self.create_hollow = print_3d.hollow_create
+        self.voxel_size = print_3d.hollow_voxel_size
+        self.make_hollow_duplicate = print_3d.make_hollow_duplicate
+        self.make_hollow_inside = print_3d.make_hollow_inside
         if context.mode == 'EDIT_MESH':
             bpy.ops.object.mode_set(mode='OBJECT')
-
-        return self.execute(context)
+        wm = context.window_manager
+        return wm.invoke_props_dialog(self)
 
 

object_print3d_utils/ui.py

@@ -102,8 +102,8 @@ class VIEW3D_PT_print3d_cleanup(View3DPrintPanel, Panel):
         # layout.operator("mesh.print3d_clean_thin", text="Wall Thickness")
 
 
-class VIEW3D_PT_print3d_transform(View3DPrintPanel, Panel):
-    bl_label = "Transform"
+class VIEW3D_PT_print3d_edit(View3DPrintPanel, Panel):
+    bl_label = "Edit"
     bl_options = {"DEFAULT_CLOSED"}
 
     def draw(self, context):
@@ -111,6 +111,7 @@ class VIEW3D_PT_print3d_transform(View3DPrintPanel, Panel):
 
         print_3d = context.scene.print_3d
 
+        layout.operator("mesh.print3d_hollow")
         layout.label(text="Scale To")
         row = layout.row(align=True)
         row.operator("mesh.print3d_scale_to_volume", text="Volume")
@@ -118,12 +119,6 @@ class VIEW3D_PT_print3d_transform(View3DPrintPanel, Panel):
         row = layout.row(align=True)
         row.operator("mesh.print3d_align_to_xy", text="Align XY")
         row.prop(print_3d, "use_alignxy_face_area")
-        layout.label(text="Hollow")
-        col = layout.column(align=True)
-        col.prop(print_3d, "hollow_create")
-        col.prop(print_3d, "hollow_offset")
-        col.prop(print_3d, "hollow_resolution")
-        col.operator("mesh.print3d_hollow", text="Create Offset Surface")
 
 
 class VIEW3D_PT_print3d_export(View3DPrintPanel, Panel):