I have a small example script, where I have a circle (radius:40), which falls down to the ground. But when I increase its radius to 80 then, only the graphics of the circle seem to change, but not the physics:
<html>
<body></body>
</html>
<script src="matter.js"></script>
<script>
var Engine = Matter.Engine,
World = Matter.World,
Bodies = Matter.Bodies
engine = Engine.create(document.body,{render:{options:{wireframes: false}}})
engine.render.options.background = "#7f7f7f"
ground = Bodies.rectangle(400,590,800,20,{isStatic:true})
World.add(engine.world, ground)
circle = Bodies.circle(400,20,40,{render:{fillStyle:"#0000ff"}})
World.add(engine.world, circle)
Engine.run(engine)
setTimeout(increaseRadius, 1500)
function increaseRadius(){
circle.circleRadius = 80
}
</script>
Advertisement
Answer
My guess is that with your approach you also have to call World.add(engine.world, circle) again and possibly remove the previous circle with the smaller radius since the engine works with a copy of the circle. Alternatively, you might be able to call the scale method on the body: http://brm.io/matter-js-docs/classes/Body.html#method_scale