calculateScaleFactor method

_ScaleFactor calculateScaleFactor(Size viewBox)

Implementation

_ScaleFactor calculateScaleFactor(Size viewBox) {
  //Scale factors
  double dx = (viewBox.width) / this.pathBoundingBox.width;
  double dy = (viewBox.height) / this.pathBoundingBox.height;

  //Applied scale factors
  late double ddx, ddy;

  //No viewport available
  assert(!(dx == 0 && dy == 0));

  //Case 1: Both width/height is specified or MediaQuery
  if (!viewBox.isEmpty) {
    if (this.customDimensions != null) {
      //Custom width/height
      ddx = dx;
      ddy = dy;
    } else {
      ddx = ddy = min(dx, dy); //Maintain resolution and viewport
    }
    //Case 2: CustomDimensions specifying only one side
  } else if (dx == 0) {
    ddx = ddy = dy;
  } else if (dy == 0) {
    ddx = ddy = dx;
  }
  return _ScaleFactor(ddx, ddy);
}