elevation method

void elevation(double elevation, { double angle = 0.0, Color color = const Color(0x33000000), double opacity = 1.0, })

Elevates the widget with a boxShadow. angle format depends on what is specified in the style widget`s constructor.

..elevation(30.0, color: Colors.grey, angle: 0.0)

Implementation

void elevation(double elevation,
    {double angle = 0.0,
    Color color = const Color(0x33000000),
    double opacity = 1.0}) {
  if (elevation == 0) return;

  angle = angleToRadians(angle, angleFormat);
  final double offsetX = sin(angle) * elevation;
  final double offsetY = cos(angle) * elevation;

  // custom curve defining the opacity
  double calculatedOpacity = (0.5 - (sqrt(elevation) / 19)) * opacity;
  if (calculatedOpacity < 0.0) calculatedOpacity = 0.0;

  final Color colorWithOpacity = color.withOpacity(calculatedOpacity);

  _styleModel.boxShadow = [
    BoxShadow(
        color: colorWithOpacity,
        blurRadius: elevation,
        spreadRadius: 0.0,
        offset: Offset(offsetX, offsetY))
  ];
}