trackball-controls.js

/**
 * @author Eberhard Graether / http://egraether.com/
 * @author Mark Lundin 	/ http://mark-lundin.com
 * @author Simone Manini / http://daron1337.github.io
 * @author Luca Antiga 	/ http://lantiga.github.io
 */

THREE.TrackballControls = function(object, domElement) {

	var _this = this;
	var STATE = {
		NONE: -1,
		ROTATE: 0,
		ZOOM: 1,
		PAN: 2,
		TOUCH_ROTATE: 3,
		TOUCH_ZOOM_PAN: 4
	};

	this.object = object;
	this.domElement = (domElement !== undefined) ? domElement : document;

	// API

	this.enabled = true;

	this.screen = {
		left: 0,
		top: 0,
		width: 0,
		height: 0
	};

	this.rotateSpeed = 1.0;
	this.zoomSpeed = 1.2;
	this.panSpeed = 0.3;

	this.noRotate = false;
	this.noZoom = false;
	this.noPan = false;

	this.staticMoving = false;
	this.dynamicDampingFactor = 0.2;

	this.minDistance = 0;
	this.maxDistance = Infinity;

	this.keys = [65 /*A*/ , 83 /*S*/ , 68 /*D*/ ];

	// internals

	this.target = new THREE.Vector3();

	var EPS = 0.000001;

	var lastPosition = new THREE.Vector3();

	var _state = STATE.NONE,
		_prevState = STATE.NONE,

		_eye = new THREE.Vector3(),

		_movePrev = new THREE.Vector2(),
		_moveCurr = new THREE.Vector2(),

		_lastAxis = new THREE.Vector3(),
		_lastAngle = 0,

		_zoomStart = new THREE.Vector2(),
		_zoomEnd = new THREE.Vector2(),

		_touchZoomDistanceStart = 0,
		_touchZoomDistanceEnd = 0,

		_panStart = new THREE.Vector2(),
		_panEnd = new THREE.Vector2();

	// for reset

	this.target0 = this.target.clone();
	this.position0 = this.object.position.clone();
	this.up0 = this.object.up.clone();

	// events

	var changeEvent = {
		type: 'change'
	};
	var startEvent = {
		type: 'start'
	};
	var endEvent = {
		type: 'end'
	};


	// methods

	this.handleResize = function() {

		if (this.domElement === document) {

			this.screen.left = 0;
			this.screen.top = 0;
			this.screen.width = window.innerWidth;
			this.screen.height = window.innerHeight;

		} else {

			var box = this.domElement.getBoundingClientRect();
			// adjustments come from similar code in the jquery offset() function
			var d = this.domElement.ownerDocument.documentElement;
			this.screen.left = box.left + window.pageXOffset - d.clientLeft;
			this.screen.top = box.top + window.pageYOffset - d.clientTop;
			this.screen.width = box.width;
			this.screen.height = box.height;

		}

	};

	this.handleEvent = function(event) {

		if (typeof this[event.type] == 'function') {

			this[event.type](event);

		}

	};

	var getMouseOnScreen = (function() {

		var vector = new THREE.Vector2();

		return function getMouseOnScreen(pageX, pageY) {

			vector.set(
				(pageX - _this.screen.left) / _this.screen.width,
				(pageY - _this.screen.top) / _this.screen.height
			);

			return vector;

		};

	}());

	var getMouseOnCircle = (function() {

		var vector = new THREE.Vector2();

		return function getMouseOnCircle(pageX, pageY) {

			vector.set(
				((pageX - _this.screen.width * 0.5 - _this.screen.left) / (_this.screen.width * 0.5)),
				((_this.screen.height + 2 * (_this.screen.top - pageY)) / _this.screen.width) // screen.width intentional
			);

			return vector;

		};

	}());

	this.rotateCamera = (function() {

		var axis = new THREE.Vector3(),
			quaternion = new THREE.Quaternion(),
			eyeDirection = new THREE.Vector3(),
			objectUpDirection = new THREE.Vector3(),
			objectSidewaysDirection = new THREE.Vector3(),
			moveDirection = new THREE.Vector3(),
			angle;

		return function rotateCamera() {

			moveDirection.set(_moveCurr.x - _movePrev.x, _moveCurr.y - _movePrev.y, 0);
			angle = moveDirection.length();

			if (angle) {

				_eye.copy(_this.object.position).sub(_this.target);

				eyeDirection.copy(_eye).normalize();
				objectUpDirection.copy(_this.object.up).normalize();
				objectSidewaysDirection.crossVectors(objectUpDirection, eyeDirection).normalize();

				objectUpDirection.setLength(_moveCurr.y - _movePrev.y);
				objectSidewaysDirection.setLength(_moveCurr.x - _movePrev.x);

				moveDirection.copy(objectUpDirection.add(objectSidewaysDirection));

				axis.crossVectors(moveDirection, _eye).normalize();

				angle *= _this.rotateSpeed;
				quaternion.setFromAxisAngle(axis, angle);

				_eye.applyQuaternion(quaternion);
				_this.object.up.applyQuaternion(quaternion);

				_lastAxis.copy(axis);
				_lastAngle = angle;

			} else if (!_this.staticMoving && _lastAngle) {

				_lastAngle *= Math.sqrt(1.0 - _this.dynamicDampingFactor);
				_eye.copy(_this.object.position).sub(_this.target);
				quaternion.setFromAxisAngle(_lastAxis, _lastAngle);
				_eye.applyQuaternion(quaternion);
				_this.object.up.applyQuaternion(quaternion);

			}

			_movePrev.copy(_moveCurr);

		};

	}());


	this.zoomCamera = function() {

		var factor;

		if (_state === STATE.TOUCH_ZOOM_PAN) {

			factor = _touchZoomDistanceStart / _touchZoomDistanceEnd;
			_touchZoomDistanceStart = _touchZoomDistanceEnd;
			_eye.multiplyScalar(factor);

		} else {

			factor = 1.0 + (_zoomEnd.y - _zoomStart.y) * _this.zoomSpeed;

			if (factor !== 1.0 && factor > 0.0) {

				_eye.multiplyScalar(factor);

			}

			if (_this.staticMoving) {

				_zoomStart.copy(_zoomEnd);

			} else {

				_zoomStart.y += (_zoomEnd.y - _zoomStart.y) * this.dynamicDampingFactor;

			}

		}

	};

	this.panCamera = (function() {

		var mouseChange = new THREE.Vector2(),
			objectUp = new THREE.Vector3(),
			pan = new THREE.Vector3();

		return function panCamera() {

			mouseChange.copy(_panEnd).sub(_panStart);

			if (mouseChange.lengthSq()) {

				mouseChange.multiplyScalar(_eye.length() * _this.panSpeed);

				pan.copy(_eye).cross(_this.object.up).setLength(mouseChange.x);
				pan.add(objectUp.copy(_this.object.up).setLength(mouseChange.y));

				_this.object.position.add(pan);
				_this.target.add(pan);

				if (_this.staticMoving) {

					_panStart.copy(_panEnd);

				} else {

					_panStart.add(mouseChange.subVectors(_panEnd, _panStart).multiplyScalar(_this.dynamicDampingFactor));

				}

			}

		};

	}());

	this.checkDistances = function() {

		if (!_this.noZoom || !_this.noPan) {

			if (_eye.lengthSq() > _this.maxDistance * _this.maxDistance) {

				_this.object.position.addVectors(_this.target, _eye.setLength(_this.maxDistance));
				_zoomStart.copy(_zoomEnd);

			}

			if (_eye.lengthSq() < _this.minDistance * _this.minDistance) {

				_this.object.position.addVectors(_this.target, _eye.setLength(_this.minDistance));
				_zoomStart.copy(_zoomEnd);

			}

		}

	};

	this.update = function() {

		_eye.subVectors(_this.object.position, _this.target);

		if (!_this.noRotate) {

			_this.rotateCamera();

		}

		if (!_this.noZoom) {

			_this.zoomCamera();

		}

		if (!_this.noPan) {

			_this.panCamera();

		}

		_this.object.position.addVectors(_this.target, _eye);

		_this.checkDistances();

		_this.object.lookAt(_this.target);

		if (lastPosition.distanceToSquared(_this.object.position) > EPS) {

			_this.dispatchEvent(changeEvent);

			lastPosition.copy(_this.object.position);

		}

	};

	this.reset = function() {

		_state = STATE.NONE;
		_prevState = STATE.NONE;

		_this.target.copy(_this.target0);
		_this.object.position.copy(_this.position0);
		_this.object.up.copy(_this.up0);

		_eye.subVectors(_this.object.position, _this.target);

		_this.object.lookAt(_this.target);

		_this.dispatchEvent(changeEvent);

		lastPosition.copy(_this.object.position);

	};

	// listeners

	function keydown(event) {

		if (_this.enabled === false) return;

		window.removeEventListener('keydown', keydown);

		_prevState = _state;

		if (_state !== STATE.NONE) {

			return;

		} else if (event.keyCode === _this.keys[STATE.ROTATE] && !_this.noRotate) {

			_state = STATE.ROTATE;

		} else if (event.keyCode === _this.keys[STATE.ZOOM] && !_this.noZoom) {

			_state = STATE.ZOOM;

		} else if (event.keyCode === _this.keys[STATE.PAN] && !_this.noPan) {

			_state = STATE.PAN;

		}

	}

	function keyup(event) {

		if (_this.enabled === false) return;

		_state = _prevState;

		window.addEventListener('keydown', keydown, false);

	}

	function mousedown(event) {

		if (_this.enabled === false) return;

		event.preventDefault();
		event.stopPropagation();

		if (_state === STATE.NONE) {

			_state = event.button;

		}

		if (_state === STATE.ROTATE && !_this.noRotate) {

			_moveCurr.copy(getMouseOnCircle(event.pageX, event.pageY));
			_movePrev.copy(_moveCurr);

		} else if (_state === STATE.ZOOM && !_this.noZoom) {

			_zoomStart.copy(getMouseOnScreen(event.pageX, event.pageY));
			_zoomEnd.copy(_zoomStart);

		} else if (_state === STATE.PAN && !_this.noPan) {

			_panStart.copy(getMouseOnScreen(event.pageX, event.pageY));
			_panEnd.copy(_panStart);

		}

		document.addEventListener('mousemove', mousemove, false);
		document.addEventListener('mouseup', mouseup, false);

		_this.dispatchEvent(startEvent);

	}

	function mousemove(event) {

		if (_this.enabled === false) return;

		event.preventDefault();
		event.stopPropagation();

		if (_state === STATE.ROTATE && !_this.noRotate) {

			_movePrev.copy(_moveCurr);
			_moveCurr.copy(getMouseOnCircle(event.pageX, event.pageY));

		} else if (_state === STATE.ZOOM && !_this.noZoom) {

			_zoomEnd.copy(getMouseOnScreen(event.pageX, event.pageY));

		} else if (_state === STATE.PAN && !_this.noPan) {

			_panEnd.copy(getMouseOnScreen(event.pageX, event.pageY));

		}

	}

	function mouseup(event) {

		if (_this.enabled === false) return;

		event.preventDefault();
		event.stopPropagation();

		_state = STATE.NONE;

		document.removeEventListener('mousemove', mousemove);
		document.removeEventListener('mouseup', mouseup);
		_this.dispatchEvent(endEvent);

	}

	function mousewheel(event) {

		if (_this.enabled === false) return;

		event.preventDefault();
		event.stopPropagation();

		switch (event.deltaMode) {

			case 2:
				// Zoom in pages
				_zoomStart.y -= event.deltaY * 0.025;
				break;

			case 1:
				// Zoom in lines
				_zoomStart.y -= event.deltaY * 0.01;
				break;

			default:
				// undefined, 0, assume pixels
				_zoomStart.y -= event.deltaY * 0.00025;
				break;

		}

		_this.dispatchEvent(startEvent);
		_this.dispatchEvent(endEvent);

	}

	function touchstart(event) {

		if (_this.enabled === false) return;

		switch (event.touches.length) {

			case 1:
				_state = STATE.TOUCH_ROTATE;
				_moveCurr.copy(getMouseOnCircle(event.touches[0].pageX, event.touches[0].pageY));
				_movePrev.copy(_moveCurr);
				break;

			default: // 2 or more
				_state = STATE.TOUCH_ZOOM_PAN;
				var dx = event.touches[0].pageX - event.touches[1].pageX;
				var dy = event.touches[0].pageY - event.touches[1].pageY;
				_touchZoomDistanceEnd = _touchZoomDistanceStart = Math.sqrt(dx * dx + dy * dy);

				var x = (event.touches[0].pageX + event.touches[1].pageX) / 2;
				var y = (event.touches[0].pageY + event.touches[1].pageY) / 2;
				_panStart.copy(getMouseOnScreen(x, y));
				_panEnd.copy(_panStart);
				break;

		}

		_this.dispatchEvent(startEvent);

	}

	function touchmove(event) {

		if (_this.enabled === false) return;

		event.preventDefault();
		event.stopPropagation();

		switch (event.touches.length) {

			case 1:
				_movePrev.copy(_moveCurr);
				_moveCurr.copy(getMouseOnCircle(event.touches[0].pageX, event.touches[0].pageY));
				break;

			default: // 2 or more
				var dx = event.touches[0].pageX - event.touches[1].pageX;
				var dy = event.touches[0].pageY - event.touches[1].pageY;
				_touchZoomDistanceEnd = Math.sqrt(dx * dx + dy * dy);

				var x = (event.touches[0].pageX + event.touches[1].pageX) / 2;
				var y = (event.touches[0].pageY + event.touches[1].pageY) / 2;
				_panEnd.copy(getMouseOnScreen(x, y));
				break;

		}

	}

	function touchend(event) {

		if (_this.enabled === false) return;

		switch (event.touches.length) {

			case 0:
				_state = STATE.NONE;
				break;

			case 1:
				_state = STATE.TOUCH_ROTATE;
				_moveCurr.copy(getMouseOnCircle(event.touches[0].pageX, event.touches[0].pageY));
				_movePrev.copy(_moveCurr);
				break;

		}

		_this.dispatchEvent(endEvent);

	}

	function contextmenu(event) {

		event.preventDefault();

	}

	this.dispose = function() {

		this.domElement.removeEventListener('contextmenu', contextmenu, false);
		this.domElement.removeEventListener('mousedown', mousedown, false);
		this.domElement.removeEventListener('wheel', mousewheel, false);

		this.domElement.removeEventListener('touchstart', touchstart, false);
		this.domElement.removeEventListener('touchend', touchend, false);
		this.domElement.removeEventListener('touchmove', touchmove, false);

		document.removeEventListener('mousemove', mousemove, false);
		document.removeEventListener('mouseup', mouseup, false);

		window.removeEventListener('keydown', keydown, false);
		window.removeEventListener('keyup', keyup, false);

	};

	this.domElement.addEventListener('contextmenu', contextmenu, false);
	this.domElement.addEventListener('mousedown', mousedown, false);
	this.domElement.addEventListener('wheel', mousewheel, false);

	this.domElement.addEventListener('touchstart', touchstart, false);
	this.domElement.addEventListener('touchend', touchend, false);
	this.domElement.addEventListener('touchmove', touchmove, false);

	window.addEventListener('keydown', keydown, false);
	window.addEventListener('keyup', keyup, false);

	this.handleResize();

	// force an update at start
	this.update();

};

THREE.TrackballControls.prototype = Object.create(THREE.EventDispatcher.prototype);
THREE.TrackballControls.prototype.constructor = THREE.TrackballControls;