covert canvas coordinate to group coordinate

[rmd1710714107]

Background:Because i want to draw a line interactively in a group, and i need to add the line to group. But mouse event point i get based on canvas coordinate, i have to covert the point to group coordinate. So i want to know how to convert the canvas coordinate to group coordinate. The code below:

function canvasToGroupLocal(canvasPoint) {
  if (!matrix) return canvasPoint.clone();

  const matrix = group.calcTransformMatrix();
  const inverseMatrix = util.invertTransform(matrix);
  return canvasPoint.transform(inverseMatrix);
  
}
function covertCanvasToGroup(absolutePointer){
  let pointer=canvasToGroupLocal(absolutePointer,matrix);
  console.log("pointer",pointer)
  const scaleX=mapGroup.scaleX||1,scaleY=mapGroup.scaleY||1;
  const x = pointer.x;
  const y = pointer.y;
  const newX = x/scaleX;
  const newY = y/scaleY;
  return { x: newX, y: newY };
}

Actually, i want to know how to draw a line interactively in a group.