How to rotate a triangle about it's center?
document.onkeydown = function (event) { switch (event.keyCode) { case 74: //player presses "j" px = player.calculateCentreX(); py = player.calculateCentreY(); x1 = rotateX(player.x1,player.y1,35,px,py); x2 = rotateX(player.x2,player.y2,35,px,py); x3 = rotateX(player.x3,player.y3,35,px,py); y1 = rotateY(player.x1,player.y1,35,px,py); y2 = rotateY(player.x2,player.y2,35,px,py); y3 = rotateY(player.x3,player.y3,35,px,py); player.setPoints(x1,y1,x2,y2,x3,y3); break; default: break; } }; function rotateX(cx,cy,angle,px,py) { x = Math.cos(angle)*(px-cx) – Math.sin(angle)*(py-cy) + cx return x… Read More How to rotate a triangle about it's center?