zoom method

ChartViewport zoom(
  1. double factor, {
  2. double centerX = 0.5,
  3. double centerY = 0.5,
})

Implementation

ChartViewport zoom(
  double factor, {
  double centerX = 0.5,
  double centerY = 0.5,
}) {
  final cx = minX + width * centerX;
  final cy = minY + height * centerY;
  final newWidth = width / factor;
  final newHeight = height / factor;
  return ChartViewport(
    minX: cx - newWidth * centerX,
    maxX: cx + newWidth * (1 - centerX),
    minY: cy - newHeight * centerY,
    maxY: cy + newHeight * (1 - centerY),
  );
}