updateScalebyDelta method

void updateScalebyDelta(
  1. double delta, {
  2. Offset? focalPoint,
})

Increment or decrement the scale by an additive delta value.

Implementation

void updateScalebyDelta(double delta, {Offset? focalPoint}) {
  // added focalPoint param
  focalPoint ??= Offset(canvasSize.width / 2, canvasSize.height / 2);
  final newScale = _scale + delta;
  _gsTopLeftOffset = newGsTopLeftOnScaling(_gsTopLeftOffset, focalPoint, _scale, newScale);
  _scale = newScale;
  markDirty();
}