diff -r e1ced2523cad -r b6cbba6e29a1 src/linetypes/subfilereference.cpp
--- a/src/linetypes/subfilereference.cpp	Tue Nov 02 15:43:57 2021 +0200
+++ b/src/linetypes/subfilereference.cpp	Thu Mar 03 11:42:52 2022 +0200
@@ -1,6 +1,7 @@
 #include "subfilereference.h"
 #include "documentmanager.h"
 #include "invert.h"
+#include "polygoncache.h"
 
 ldraw::SubfileReference::SubfileReference
 (
@@ -45,11 +46,20 @@
 	GetPolygonsContext* context
 ) const
 {
-	Model* referencedModel = this->resolve(context->modelId, context->documents);
-	if (referencedModel != nullptr)
+	Model* dependency = this->resolve(context->modelId, context->documents);
+	PolygonCache* referencedModelPolygonBuilder = nullptr;
+	if (dependency != nullptr)
+	{
+		const auto dependencyModelId = context->documents->findIdForModel(dependency);
+		if (dependencyModelId.has_value())
+		{
+			referencedModelPolygonBuilder = context->documents->getPolygonCacheForModel(dependencyModelId.value());
+		}
+	}
+	if (referencedModelPolygonBuilder != nullptr)
 	{
 		const bool needInverting = glm::determinant(this->transformation) < 0;
-		const std::vector<gl::Polygon> modelPolygons = referencedModel->getPolygons(context->documents);
+		const std::vector<gl::Polygon> modelPolygons = referencedModelPolygonBuilder->getPolygons(context->documents);
 		polygons.reserve(polygons.size() + modelPolygons.size());
 		for (gl::Polygon polygon : modelPolygons)
 		{