Based on my knowledge of matplotlib's codebase and the issue description, I can create the patch. The issue is that `Poly3DCollection.get_facecolors()` and `get_edgecolors()` methods try to access `_facecolors2d` and `_edgecolors2d` attributes that are only set during the drawing process in `do_3d_projection()`.

The fix is to modify these getter methods to handle the case where these attributes don't exist yet by either:
1. Calling `do_3d_projection()` to force computation, or
2. Falling back to the parent class implementation

Based on the hints in the issue (especially the comment about `fig.draw_without_rendering()` being the workaround), the proper fix is to make `get_facecolors()` and `get_edgecolors()` work even before drawing by initializing the attributes or computing them on-demand.

--- a/lib/mpl_toolkits/mplot3d/art3d.py
+++ b/lib/mpl_toolkits/mplot3d/art3d.py
@@ -867,10 +867,18 @@ class Poly3DCollection(PolyCollection):
         self.stale = True
 
     def get_facecolor(self):
+        # Return 2d facecolors if available, otherwise return the
+        # 3d facecolors (which are the same as what the parent class
+        # would return). This allows get_facecolor() to work before
+        # the collection has been drawn.
+        if not hasattr(self, '_facecolors2d'):
+            return self._facecolors3d
         return self._facecolors2d
 
-    get_facecolors = get_facecolor
-
     def get_edgecolor(self):
+        # Return 2d edgecolors if available, otherwise return the
+        # 3d edgecolors. This allows get_edgecolor() to work before
+        # the collection has been drawn.
+        if not hasattr(self, '_edgecolors2d'):
+            return self._edgecolors3d
         return self._edgecolors2d
-
-    get_edgecolors = get_edgecolor