jellyTransform static method

Matrix4 jellyTransform({ required Offset velocity, double maxDistortion = 0.7, double velocityScale = 1000.0, })

Creates a jelly transform matrix based on velocity.

Implementation

static Matrix4 jellyTransform({
  required Offset velocity,
  double maxDistortion = 0.7,
  double velocityScale = 1000.0,
}) {
  final speed = velocity.distance;
  if (speed == 0) return Matrix4.identity();

  final direction = velocity / speed;
  final distortionFactor =
      (speed / velocityScale).clamp(0.0, 1.0) * maxDistortion;

  final squashX = 1.0 - (direction.dx.abs() * distortionFactor * 0.5);
  final squashY = 1.0 - (direction.dy.abs() * distortionFactor * 0.5);
  final stretchX = 1.0 + (direction.dy.abs() * distortionFactor * 0.3);
  final stretchY = 1.0 + (direction.dx.abs() * distortionFactor * 0.3);

  final scaleX = squashX * stretchX;
  final scaleY = squashY * stretchY;

  return Matrix4.identity()..scale(scaleX, scaleY);
}