docs: @SuppressWarnings("unused")
      private void allocateBuffers(int numVertices) {
          /*
           * the allocated buffers are native order direct byte buffers, so they
           * can be passed directly to LWJGL or similar graphics APIs
           */
  
          m_numVertices = numVertices;
  
          /* allocate for each vertex 3 floats */
          if (m_numVertices > 0) {
              m_vertices = ByteBuffer.allocateDirect(numVertices * 3 *
                      SIZEOF_FLOAT);
              m_vertices.order(ByteOrder.nativeOrder());
          }
  
      }