1 files changed, 80 insertions, 0 deletions
diff --git a/public/assets/javascripts/mx/extensions/mx.orbitCamera.js b/public/assets/javascripts/mx/extensions/mx.orbitCamera.js
new file mode 100644
index 0000000..b3dcc43
--- /dev/null
+++ b/public/assets/javascripts/mx/extensions/mx.orbitCamera.js
@@ -0,0 +1,80 @@
+MX.OrbitCamera = function(opt){
+	var exports = {}, bound = false
+	exports.opt = opt = defaults(opt, {
+		el: window,                   // object to bind events on
+		camera: scene.camera,         // camera object we'll be moving
+		radius: 100,
+		radiusRange: [ 10, 1000 ],
+		rotationX: PI/2,
+		rotationY: 0,
+		center: { x: 0, y: 0, z: 0 },
+		sensitivity: 10,              // moving 1 pixel is like moving N radians
+		ease: 10,
+	})
+	var rx, ry, px, py, epsilon = 1e-10, dragging = false
+	exports.init = function(){
+    ry = opt.rotationY
+    rx = opt.rotationX
+		exports.bind()
+	}
+	exports.toggle = function(state){
+		if (state) exports.bind()
+		else exports.unbind()
+	}
+	exports.bind = function(){
+		if (bound) return;
+		bound = true
+		opt.el.addEventListener("mousedown", down)
+		opt.el.addEventListener("mousemove", move)
+		opt.el.addEventListener("mouseup", up)
+	}
+	exports.unbind = function(){
+		if (! bound) return;
+		bound = false
+		opt.el.removeEventListener("mousedown", down)
+		opt.el.removeEventListener("mousemove", move)
+		opt.el.removeEventListener("mouseup", up)
+	}
+	function down (e) {
+	  px = e.pageX
+	  py = e.pageY
+	  dragging = true
+	}
+	function move (e) {
+	  if (! dragging) return
+	  exports.delta(px- e.pageX, py - e.pageY)
+	  px = e.pageX
+	  py = e.pageY
+	}
+	function up (e) {
+	  dragging = false
+	}
+	exports.delta = function(x,y){
+	  opt.rotationY += x/window.innerWidth * opt.sensitivity
+	  opt.rotationX = clamp( opt.rotationX + y/window.innerHeight * opt.sensitivity, 0, PI)
+	}
+	exports.move = function(y, x){
+	  opt.rotationY = y
+	  if (typeof x == "number") { opt.rotationX = x }
+	}
+	exports.update = function(){
+	  if (abs(ry - opt.rotationY) > epsilon) {
+      ry = avg(ry, opt.rotationY, opt.ease)
+	  }
+	  else {
+	    ry = opt.rotationY
+	  }
+	  if (abs(rx - opt.rotationX) > epsilon) {
+      rx = avg(rx, opt.rotationX, opt.ease)
+	  }
+	  else {
+	    rx = opt.rotationX
+	  }
+		opt.camera.x = opt.center.x + opt.radius * sin(rx) * cos(ry)
+		opt.camera.z = opt.center.y + opt.radius * sin(rx) * sin(ry)
+		opt.camera.y = opt.center.z + opt.radius * cos(rx)
+ 		opt.camera.rotationX = PI/2 - rx
+ 		opt.camera.rotationY = ry + PI/2
+	}
+	return exports
+}