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HTML
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CSS
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JS 

              
                import Two from 'https://cdn.skypack.dev/two.js@latest';

var two = new Two({
  type: Two.Types.svg,
  fullscreen: true,
  autostart: true,
}).appendTo(document.body);

var mouse = new Two.Vector();
var rect;

var path = new Two.Star(0, 0, two.height * 0.0625, two.height * 0.33, 9);
path.scale = new Two.Vector(1, 1);
path.position.set(two.width / 2, two.height / 2);
path.closed = true;
path.curved = true;
path.fill = new Two.LinearGradient(0, 0, 0, 1, [
  new Two.Stop(0, 'orange'),
  new Two.Stop(1, 'red'),
]);
path.noStroke();

var box = new Two.Rectangle(0, 0, 0, 0);
box.stroke = '#00AEFF';
box.noFill();

var endpoints = new Two.Points(box.vertices);
endpoints.size = 6;
endpoints.fill = '#00AEFF';
endpoints.noStroke();

var stage = new Two.Group();
var ui = new Two.Group();
var text = new Two.Text(`Operation: none`, 0, 0, {
  size: 17,
  baseline: 'bottom',
});

stage.add(path);
ui.add(box, endpoints);
two.add(stage, ui, text);

two.bind('update', update).bind('resize', resize);

resize();

var domElement = two.renderer.domElement;

domElement.addEventListener('pointerdown', pointerdown, false);
domElement.addEventListener('pointermove', pointermove, false);
domElement.addEventListener('pointerup', pointerup, false);

function resize() {
  text.position.x = two.width / 2;
  text.position.y = two.height - text.size;
}

function update(frameCount) {
  var minX = Infinity;
  var minY = Infinity;
  var maxX = -Infinity;
  var maxY = -Infinity;

  for (var i = 0; i < 1; i += 0.01) {
    var v = path.getPointAt(i);
    minX = Math.min(minX, v.x * path.scale.x);
    maxX = Math.max(maxX, v.x * path.scale.x);
    minY = Math.min(minY, v.y * path.scale.y);
    maxY = Math.max(maxY, v.y * path.scale.y);
  }

  box.width = maxX - minX;
  box.height = maxY - minY;

  ui.position = path.position;
  ui.rotation = path.rotation;
}

//

var dragging = false,
  scaling = false,
  rotating = false,
  start = new Two.Vector(),
  initialPosition = new Two.Vector(),
  initialRotation = 0;

function pointerdown(e) {
  var rect = box.getBoundingClientRect();

  mouse.x = e.clientX;
  mouse.y = e.clientY;

  dragging = true;

  rotating = atCorner(box, mouse);
  if (rotating) {
    initialRotation = path.rotation;
    // Store initial distance for proper rotation
    start.set(e.clientX - path.position.x, e.clientY - path.position.y);
  }

  scaling = !rotating && atCorner(box, mouse, 25);
  if (scaling) {
    mouse.scale = path.scale.clone();
    mouse.corner = scaling;
    // Store initial values for scaling
    start.copy(mouse);
    mouse.initialWidth = box.width;
    mouse.initialHeight = box.height;
    // Store path's original position
    initialPosition.copy(path.position);
  }

  // For positioning
  if (!rotating && !scaling && contains(rect, mouse)) {
    mouse.isPositioning = true;
  } else {
    mouse.isPositioning = false;
  }
}

function pointermove(e) {
  var rect = box.getBoundingClientRect();
  var dx = e.clientX - mouse.x;
  var dy = e.clientY - mouse.y;

  var isRotating = atCorner(box, mouse);
  var isScaling = atCorner(box, mouse, 25);
  var isPositioning = !isRotating && !isScaling && contains(rect, mouse);

  // Update current mouse position
  mouse.x = e.clientX;
  mouse.y = e.clientY;

  // Update cursor style and operation text
  if (rotating || isRotating) {
    two.renderer.domElement.style.cursor = 'alias';
    text.value = `Operation: rotate`;
  } else if (scaling || isScaling) {
    two.renderer.domElement.style.cursor = scaling
      ? scaling.name
      : 'ns-resize';
    text.value = `Operation: scale`;
  } else if (isPositioning) {
    two.renderer.domElement.style.cursor = dragging ? 'grabbing' : 'grab';
    text.value = `Operation: position`;
  } else {
    two.renderer.domElement.style.cursor = 'default';
    text.value = `Operation: none`;
  }

  if (!dragging) {
    return;
  }

  if (rotating) {
    text.value = 'Operation: rotating';

    // Calculate angle from center to current mouse position
    const currentAngle = Math.atan2(
      e.clientY - path.position.y,
      e.clientX - path.position.x
    );

    // Calculate angle from center to starting position
    const startAngle = Math.atan2(start.y, start.x);

    // Apply rotation as difference between angles
    path.rotation = initialRotation + (currentAngle - startAngle);
  } else if (scaling) {
    text.value = 'Operation: scaling';

    // Calculate scale factors based on mouse movement
    let deltaX = mouse.x - start.x;
    let deltaY = mouse.y - start.y;

    // Adjust for shape rotation
    if (path.rotation !== 0) {
      const cos = Math.cos(-path.rotation);
      const sin = Math.sin(-path.rotation);
      const rotatedDeltaX = deltaX * cos - deltaY * sin;
      const rotatedDeltaY = deltaX * sin + deltaY * cos;
      deltaX = rotatedDeltaX;
      deltaY = rotatedDeltaY;
    }

    // Calculate new dimensions
    let newWidth, newHeight;
    let scaleX, scaleY;

    // Different scaling logic based on which corner is being dragged
    if (mouse.corner.name === 'se-resize') {
      newWidth = mouse.initialWidth + deltaX;
      newHeight = mouse.initialHeight + deltaY;
    } else if (mouse.corner.name === 'sw-resize') {
      newWidth = mouse.initialWidth - deltaX;
      newHeight = mouse.initialHeight + deltaY;
    } else if (mouse.corner.name === 'ne-resize') {
      newWidth = mouse.initialWidth + deltaX;
      newHeight = mouse.initialHeight - deltaY;
    } else if (mouse.corner.name === 'nw-resize') {
      newWidth = mouse.initialWidth - deltaX;
      newHeight = mouse.initialHeight - deltaY;
    }

    // Calculate scale factors
    scaleX = newWidth / mouse.initialWidth;
    scaleY = newHeight / mouse.initialHeight;

    // Apply aspect ratio constraint with Shift key
    if (e.shiftKey) {
      const ratio = Math.min(Math.abs(scaleX), Math.abs(scaleY));
      scaleX = scaleX >= 0 ? ratio : -ratio;
      scaleY = scaleY >= 0 ? ratio : -ratio;
    }

    // Apply the new scale
    path.scale.x = mouse.scale.x * scaleX;
    path.scale.y = mouse.scale.y * scaleY;

    // Adjust position to handle anchored scaling from corners
    const anchorOffsetX = (mouse.initialWidth * (scaleX - 1)) / 2;
    const anchorOffsetY = (mouse.initialHeight * (scaleY - 1)) / 2;

    // Calculate position adjustment based on corner
    let adjustX = 0,
      adjustY = 0;

    if (mouse.corner.name === 'nw-resize') {
      adjustX = -anchorOffsetX;
      adjustY = -anchorOffsetY;
    } else if (mouse.corner.name === 'ne-resize') {
      adjustX = anchorOffsetX;
      adjustY = -anchorOffsetY;
    } else if (mouse.corner.name === 'sw-resize') {
      adjustX = -anchorOffsetX;
      adjustY = anchorOffsetY;
    } else if (mouse.corner.name === 'se-resize') {
      adjustX = anchorOffsetX;
      adjustY = anchorOffsetY;
    }

    // Apply position adjustment with rotation considered
    if (path.rotation !== 0) {
      const cos = Math.cos(path.rotation);
      const sin = Math.sin(path.rotation);
      const rotatedX = adjustX * cos - adjustY * sin;
      const rotatedY = adjustX * sin + adjustY * cos;
      path.position.x = initialPosition.x + rotatedX;
      path.position.y = initialPosition.y + rotatedY;
    } else {
      path.position.x = initialPosition.x + adjustX;
      path.position.y = initialPosition.y + adjustY;
    }

    // Scale from center with Alt key
    if (e.altKey) {
      path.position.x = initialPosition.x;
      path.position.y = initialPosition.y;
    }

    // Add modifier keys info
    if (e.shiftKey) {
      text.value += ' (constrained)';
    }
    if (e.altKey) {
      text.value += ' (from center)';
    }
  } else if (mouse.isPositioning) {
    text.value = 'Operation: positioning';
    two.renderer.domElement.style.cursor = 'grabbing';
    path.position.add(dx, dy);
  }
}

function pointerup() {
  dragging = false;
  scaling = false;
  rotating = false;
  mouse.isPositioning = false;
  two.renderer.domElement.style.cursor = 'default';
}

//

function contains(rect, point) {
  return (
    point.x > rect.left &&
    point.x < rect.right &&
    point.y > rect.top &&
    point.y < rect.bottom
  );
}

function atCorner(object, point, limit) {
  var v;

  if (typeof limit !== 'number') {
    limit = 10;
  }

  limit *= limit;

  var matrix = Two.Utils.getComputedMatrix(object);

  v = object.vertices[0];
  var tl = matrix.multiply(v.x, v.y, 1);
  v = object.vertices[1];
  var tr = matrix.multiply(v.x, v.y, 1);
  v = object.vertices[2];
  var bl = matrix.multiply(v.x, v.y, 1);
  v = object.vertices[3];
  var br = matrix.multiply(v.x, v.y, 1);
  var dbs = Two.Vector.distanceBetweenSquared;

  if (dbs(point, { x: tl[0], y: tl[1] }) < limit) {
    return { name: 'nw-resize', point: object.vertices[0] };
  } else if (dbs(point, { x: tr[0], y: tr[1] }) < limit) {
    return { name: 'ne-resize', point: object.vertices[1] };
  } else if (dbs(point, { x: bl[0], y: bl[1] }) < limit) {
    return { name: 'se-resize', point: object.vertices[2] };
  } else if (dbs(point, { x: br[0], y: br[1] }) < limit) {
    return { name: 'sw-resize', point: object.vertices[3] };
  } else {
    return false;
  }
}

function getOppositeCorner(cornerName) {
  switch (cornerName) {
    case 'nw-resize':
      return 'se-resize';
    case 'ne-resize':
      return 'sw-resize';
    case 'sw-resize':
      return 'ne-resize';
    case 'se-resize':
      return 'nw-resize';
    default:
      return null;
  }
}

// Helper function to rotate a point around origin
function rotatePoint(point, angle) {
  const cos = Math.cos(angle);
  const sin = Math.sin(angle);
  return {
    x: point.x * cos - point.y * sin,
    y: point.x * sin + point.y * cos,
  };
}
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