Resize rectangle in Paper.js

Question

I have a very ordinary rectangle created in Paper.js and I'd like to resize it, but I can't find any obvious ways to do it.

var rect = new Rectangle([0, 0],[width,height]);
rect.center = mousePoint;
var path = new Path.Rectangle(rect, 4);
path.fillColor = fillColor;
path.meta = fillColor;

There's a scale transformation method, but it's not really for mouse interaction and my goal is to create a handle that can resize a component.

Answer 1

Note that PaperJS has three different kinds of Rectangles:

• Rectangle — This is the basic type (data structure) that defines a rectangle. Basically, top-left point, width, and height. (Nothing is displayed on the screen.) This kind of rectangle can be resized by setting its size property, for instance:

  let rect;
  const originalSize = [50, 50];
  const newSize = [100, 100];
  
  rect = new Rectangle([10, 50], originalSize);
  rect.size = newSize;
  

• Path.Rectangle — This is a method for generating a list of Segments that make up a rectangular-shaped Path. This does get displayed, but a Path lacks methods associated with a rectangle. For instance, a Path.Rectangle has no size property (so trying to modify it has no effect). To resize a Path you can use the scale() method as another answer proposes, or modify its Segments:

  rect = new Path.Rectangle([210, 50], originalSize);
  rect.strokeColor = "red";
  rect.strokeWidth = 3;
  
  rect.segments[0].point = rect.segments[0].point.add([-25, 25]);  // lower left point
  rect.segments[1].point = rect.segments[1].point.add([-25, -25]); // upper left point
  rect.segments[2].point = rect.segments[2].point.add([25, -25]);  // upper right point
  rect.segments[3].point = rect.segments[3].point.add([25, 25]);  // lower right point
  
  

• Shape.Rectangle — This kind of rectangle gets displayed and exposes properties about its shape, such as size. To resize a Shape.Rectangle you can modify its size property directly:

  rect = new Shape.Rectangle([410, 50], originalSize)
  rect.strokeColor = "blue"
  rect.strokeWidth = 3
  
  rect.size = newSize
  

Most likely, if you want to draw a rectangle and modify its properties after the fact, the rectangle you are looking for is Shape.Rectangle.

Here is a Sketch that lets you play around with the different kinds of rectangles.