title: Fabric.js Clip Canvas (or object group) To Polygon
body: <p>I have a canvas drawn in Fabric.js that i am adding a group of rectangles to, i want to limit the edges of those rectangles as a group to not go outside a certain area.</p>
  
  <p>Imagine making a stripy t-shirt, the stripes are make by using a series of rectangles and i need to keep them to the shape of the t-shirt.</p>
  
  <p>I think its better to clip the entire canvas to the shape of the t shirt, so anything i add to it remains within the t-shirt but i am stuck. So far i am only clip to basic circles and rectangles.</p>
  
  <p>Thanks</p>