             through: through,
             by: subdiv.rawValue
         ).map({ _PositionIndex(value: $0, subdivision: subdiv) })
-    }
-    
-    private func _lineColor(for line: LineLayer) -> CGColor {
-        if line._positionIndex.subdivision == .none {
-            return self.mainGridLineColor
-        } else {
-            return self.subGridLineColor
-        }
     }
 }
 

}


// MARK: Update LineLayers
private extension GridLayer {
    func _updateRowLineLengths() {

        var columnIndices: [_PositionIndex] = []
        
        for line in self._lineLayers {
            switch line.orientation {
            case .horizontal:   rowIndices.append(line._positionIndex)
            case .vertical:     columnIndices.append(line._positionIndex)
            }
        }
        
