Settings.GetPixel() and Settings.GetLocation() are not thread safe.
This break Signal and SignalConst parallel render.
This methods use xAxisScale and yAxisScale, and they reference to Bitmap(bmpData). Bitmap class not thread safe.
Will it possible to make xAxisScale regular field, and update it then bitmap size actually changed?

Additionaly it will be usefull to have some GetPixelX() and GetPixelY(). It allow to make a bit optimizations to signal render. In some cases it need to calc only one coordinate.