Refactored file layout because platformio failed to find things

src/CMakeLists.txt

@@ -1,4 +1,59 @@
-add_subdirectory(Matrix)
-add_subdirectory(Quaternion)
-add_subdirectory(Vector3D)
+# Quaternion Interface
+add_library(vector-3d-intf
+    INTERFACE
+)
 
+target_include_directories(vector-3d-intf
+    INTERFACE
+    .
+)
+
+target_link_libraries(vector-3d-intf
+    INTERFACE
+)
+
+# Quaternion
+add_library(quaternion 
+    STATIC
+    Quaternion.cpp
+)
+
+target_link_libraries(quaternion
+    PUBLIC
+    vector-3d-intf
+    PRIVATE
+)
+
+set_target_properties(quaternion
+    PROPERTIES
+    LINKER_LANGUAGE CXX
+)
+
+# Vector3d
+add_library(vector-3d 
+    STATIC
+    Vector3D.cpp
+)
+
+target_link_libraries(vector-3d
+    PUBLIC
+    vector-3d-intf
+    PRIVATE
+)
+
+# Matrix
+add_library(matrix 
+    STATIC
+    Matrix.cpp
+)
+
+target_link_libraries(matrix
+    PUBLIC
+    vector-3d-intf
+    PRIVATE
+)
+
+set_target_properties(matrix
+    PROPERTIES
+    LINKER_LANGUAGE CXX
+)