Tech ENABLE_RAYCAST_PICKING - Raytraced picking of volumes

src/slic3r/GUI/3DScene.hpp

@@ -10,6 +10,9 @@
 #include "libslic3r/Color.hpp"
 
 #include "GLModel.hpp"
+#if ENABLE_RAYCAST_PICKING
+#include "MeshUtils.hpp"
+#endif // ENABLE_RAYCAST_PICKING
 
 #include <functional>
 #include <optional>
@@ -392,6 +395,10 @@ public:
 
 #if ENABLE_LEGACY_OPENGL_REMOVAL
     GUI::GLModel            model;
+#if ENABLE_RAYCAST_PICKING
+    // raycaster used for picking
+    std::unique_ptr<GUI::MeshRaycaster> mesh_raycaster;
+#endif // ENABLE_RAYCAST_PICKING
 #else
     // Interleaved triangles & normals with indexed triangles & quads.
     GLIndexedVertexArray        indexed_vertex_array;