scaledPadding static method

EdgeInsetsGeometry scaledPadding(
  1. EdgeInsetsGeometry geometry1x,
  2. EdgeInsetsGeometry geometry2x,
  3. EdgeInsetsGeometry geometry3x,
  4. double fontSizeMultiplier
)

A convenience method used by subclasses in the framework, that returns an interpolated value based on the fontSizeMultiplier parameter:

  • 0 - 1 geometry1x
  • 1 - 2 lerp(geometry1x, geometry2x, fontSizeMultiplier - 1)
  • 2 - 3 lerp(geometry2x, geometry3x, fontSizeMultiplier - 2)
  • otherwise geometry3x

This method is used by the framework for estimating the default paddings to use on a button with a text label, when the system text scaling setting changes. It's usually supplied with empirical geometry1x, geometry2x, geometry3x values adjusted for different system text scaling values, when the unscaled font size is set to 14.0 (the default TextTheme.labelLarge value).

The fontSizeMultiplier argument, for historical reasons, is the default font size specified in the ButtonStyle, scaled by the ambient font scaler, then divided by 14.0 (the default font size used in buttons).

Implementation

static EdgeInsetsGeometry scaledPadding(
  EdgeInsetsGeometry geometry1x,
  EdgeInsetsGeometry geometry2x,
  EdgeInsetsGeometry geometry3x,
  double fontSizeMultiplier,
) {
  return switch (fontSizeMultiplier) {
    <= 1 => geometry1x,
    < 2  => EdgeInsetsGeometry.lerp(geometry1x, geometry2x, fontSizeMultiplier - 1)!,
    < 3  => EdgeInsetsGeometry.lerp(geometry2x, geometry3x, fontSizeMultiplier - 2)!,
    _    => geometry3x,
  };
}