Store data received from messages

Took a while to get right, but this seems to work well. Now let's see if we can visualise them...

1 files changed, 47 insertions, 3 deletions

diff --git a/plugins/StructureView/StructureView.py b/plugins/StructureView/StructureView.py
index c05c7220ae..98dd22b716 100644
--- a/plugins/StructureView/StructureView.py
+++ b/plugins/StructureView/StructureView.py
@@ -1,16 +1,28 @@
 # Copyright (c) 2022 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-from typing import Optional
+from typing import Optional, TYPE_CHECKING
+import numpy
 
 from cura.CuraView import CuraView
 from cura.Scene.CuraSceneNode import CuraSceneNode
 from UM.PluginRegistry import PluginRegistry
 
+if TYPE_CHECKING:
+    import pyArcus
+
 class StructureView(CuraView):
     def __init__(self):
         super().__init__(parent = None, use_empty_menu_placeholder = True)
         self._root_node = None  # type: Optional[CuraSceneNode]  # All structure data will be under this node. Will be generated on first message received (since there is no scene yet at init).
+        self._capacity = 3 * 10000  # Start with some allocation to prevent having to reallocate all the time. Preferably a multiple of 3 (for triangles).
+        self._vertices = numpy.ndarray((self._capacity, 3), dtype = numpy.single)
+        self._indices = numpy.arange(self._capacity)  # Since we're using a triangle list, the indices are simply increasing linearly.
+        self._normals = numpy.repeat([[0.0, 1.0, 0.0]], self._capacity, axis = 0)  # All normals are pointing up (to positive Y).
+        self._colors = numpy.repeat([[0.0, 0.0, 0.0]], self._capacity, axis = 0)  # No colors yet.
+        self._layers = numpy.repeat(-1, self._capacity)  # To mask out certain layers for layer view.
+
+        self._current_index = 0  # type: int  # Where to add new data.
 
         plugin_registry = PluginRegistry.getInstance()
         self._enabled = "StructureView" not in plugin_registry.getDisabledPlugins()  # Don't influence performance if this plug-in is disabled.
@@ -18,5 +30,37 @@ class StructureView(CuraView):
             engine = plugin_registry.getPluginObject("CuraEngineBackend")
             engine.structurePolygonReceived.connect(self._onStructurePolygonReceived)  # type: ignore
 
-    def _onStructurePolygonReceived(self, message):
-        print("Received structure polygon for layer", message.layer_index)
+    def _onStructurePolygonReceived(self, message: "pyArcus.PythonMessage") -> None:
+        """
+        Store the structure polygon in the scene node's mesh data when we receive one.
+        :param message: A message received from CuraEngine containing a structure polygon.
+        """
+        num_vertices = int(len(message.points) / 4 / 3)  # Number of bytes, / 4 for bytes per float, / 3 for X, Y and Z coordinates.
+        vertex_data = numpy.frombuffer(message.points, dtype = numpy.single)
+        vertex_data = numpy.reshape(vertex_data, newshape = (num_vertices, 3))
+
+        if self._current_index + num_vertices >= self._capacity:
+            self._reallocate(self._current_index + num_vertices)
+
+        to = self._current_index + num_vertices
+        self._vertices[self._current_index:to, 0:3] = vertex_data
+        self._colors[self._current_index:to] = [1.0, 0.0, 0.0]  # TODO: Placeholder color red. Use proper colour depending on structure type.
+        self._layers[self._current_index:to] = message.layer_index
+
+        self._current_index += num_vertices
+
+    def _reallocate(self, minimum_capacity: int) -> None:
+        """
+        Increase capacity to be able to hold at least a given amount of vertices.
+        """
+        new_capacity = self._capacity
+        while minimum_capacity > new_capacity:
+            new_capacity *= 2
+
+        self._vertices.resize((new_capacity, 3))
+        self._indices = numpy.arange(new_capacity)
+        self._normals = numpy.repeat([0, 1, 0], self._capacity, axis = 0)
+        self._colors.resize((new_capacity, 3))
+        self._layers.resize((new_capacity, ))
+
+        self._capacity = new_capacity