Implement build volume checks on objects

Currently using a dynamic property on SceneNode since I have not found a
better solution yet.

BuildVolume.py

@@ -6,6 +6,7 @@ from UM.Mesh.MeshData import MeshData
 from UM.Mesh.MeshBuilder import MeshBuilder
 from UM.Math.Vector import Vector
 from UM.Math.Color import Color
+from UM.Math.AxisAlignedBox import AxisAlignedBox
 
 import numpy
 
@@ -27,6 +28,8 @@ class BuildVolume(SceneNode):
         self._disallowed_areas = []
         self._disallowed_area_mesh = None
 
+        self._calculate_aabb = False
+
     def setWidth(self, width):
         self._width = width
 
@@ -117,3 +120,5 @@ class BuildVolume(SceneNode):
             self._disallowed_area_mesh = mb.getData()
         else:
             self._disallowed_area_mesh = None
+
+        self._aabb = AxisAlignedBox(minimum = Vector(minW, minH, minD), maximum = Vector(maxW, maxH, maxD))

PlatformPhysics.py

@@ -3,6 +3,7 @@ from UM.Scene.Iterator.BreadthFirstIterator import BreadthFirstIterator
 from UM.Operations.TranslateOperation import TranslateOperation
 from UM.Math.Float import Float
 from UM.Math.Vector import Vector
+from UM.Math.AxisAlignedBox import AxisAlignedBox
 from UM.Application import Application
 
 from PlatformPhysicsOperation import PlatformPhysicsOperation
@@ -11,10 +12,11 @@ import time
 import threading
 
 class PlatformPhysics:
-    def __init__(self, controller):
+    def __init__(self, controller, volume):
         super().__init__()
         self._controller = controller
         self._controller.getScene().sceneChanged.connect(self._onSceneChanged)
+        self._build_volume = volume
         self._signal_source = None
 
     def _onSceneChanged(self, source):
@@ -27,6 +29,11 @@ class PlatformPhysics:
             if not bbox or not bbox.isValid():
                 continue
 
+            if self._build_volume.getBoundingBox().intersectsBox(bbox) != AxisAlignedBox.IntersectionResult.FullIntersection:
+                node._outside_buildarea = True
+            else:
+                node._outside_buildarea = False
+
             if not Float.fuzzyCompare(bbox.bottom, 0.0):
                 self._signal_source = node
                 op = PlatformPhysicsOperation(node, Vector(0, -bbox.bottom, 0))

PrinterApplication.py

@@ -87,8 +87,6 @@ class PrinterApplication(QtApplication):
 
         Selection.selectionChanged.connect(self.onSelectionChanged)
 
-        self._physics = PlatformPhysics(controller)
-
         root = controller.getScene().getRoot()
         self._platform = Platform(root)
 
@@ -97,6 +95,8 @@ class PrinterApplication(QtApplication):
         self.getRenderer().setLightPosition(Vector(0, 150, 0))
         self.getRenderer().setBackgroundColor(QColor(245, 245, 245))
 
+        self._physics = PlatformPhysics(controller, self._volume)
+
         camera = Camera('3d', root)
         camera.setPosition(Vector(-150, 150, 300))
         camera.setPerspective(True)