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| 1 | +// THREEx.KeyboardState.js keep the current state of the keyboard. |
| 2 | +// It is possible to query it at any time. No need of an event. |
| 3 | +// This is particularly convenient in loop driven case, like in |
| 4 | +// 3D demos or games. |
| 5 | +// |
| 6 | +// # Usage |
| 7 | +// |
| 8 | +// **Step 1**: Create the object |
| 9 | +// |
| 10 | +// ```var keyboard = new THREEx.KeyboardState();``` |
| 11 | +// |
| 12 | +// **Step 2**: Query the keyboard state |
| 13 | +// |
| 14 | +// This will return true if shift and A are pressed, false otherwise |
| 15 | +// |
| 16 | +// ```keyboard.pressed("shift+A")``` |
| 17 | +// |
| 18 | +// **Step 3**: Stop listening to the keyboard |
| 19 | +// |
| 20 | +// ```keyboard.destroy()``` |
| 21 | +// |
| 22 | +// NOTE: this library may be nice as standaline. independant from three.js |
| 23 | +// - rename it keyboardForGame |
| 24 | +// |
| 25 | +// # Code |
| 26 | +// |
| 27 | + |
| 28 | +/** @namespace */ |
| 29 | +var THREEx = THREEx || {}; |
| 30 | + |
| 31 | +/** |
| 32 | + * - NOTE: it would be quite easy to push event-driven too |
| 33 | + * - microevent.js for events handling |
| 34 | + * - in this._onkeyChange, generate a string from the DOM event |
| 35 | + * - use this as event name |
| 36 | +*/ |
| 37 | +THREEx.KeyboardState = function() |
| 38 | +{ |
| 39 | + // to store the current state |
| 40 | + this.keyCodes = {}; |
| 41 | + this.modifiers = {}; |
| 42 | + |
| 43 | + // create callback to bind/unbind keyboard events |
| 44 | + var self = this; |
| 45 | + this._onKeyDown = function(event){ self._onKeyChange(event, true); }; |
| 46 | + this._onKeyUp = function(event){ self._onKeyChange(event, false);}; |
| 47 | + |
| 48 | + // bind keyEvents |
| 49 | + document.addEventListener("keydown", this._onKeyDown, false); |
| 50 | + document.addEventListener("keyup", this._onKeyUp, false); |
| 51 | +} |
| 52 | + |
| 53 | +/** |
| 54 | + * To stop listening of the keyboard events |
| 55 | +*/ |
| 56 | +THREEx.KeyboardState.prototype.destroy = function() |
| 57 | +{ |
| 58 | + // unbind keyEvents |
| 59 | + document.removeEventListener("keydown", this._onKeyDown, false); |
| 60 | + document.removeEventListener("keyup", this._onKeyUp, false); |
| 61 | +} |
| 62 | + |
| 63 | +THREEx.KeyboardState.MODIFIERS = ['shift', 'ctrl', 'alt', 'meta']; |
| 64 | +THREEx.KeyboardState.ALIAS = { |
| 65 | + 'left' : 37, |
| 66 | + 'up' : 38, |
| 67 | + 'right' : 39, |
| 68 | + 'down' : 40, |
| 69 | + 'space' : 32, |
| 70 | + 'pageup' : 33, |
| 71 | + 'pagedown' : 34, |
| 72 | + 'tab' : 9 |
| 73 | +}; |
| 74 | + |
| 75 | +/** |
| 76 | + * to process the keyboard dom event |
| 77 | +*/ |
| 78 | +THREEx.KeyboardState.prototype._onKeyChange = function(event, pressed) |
| 79 | +{ |
| 80 | + // log to debug |
| 81 | + //console.log("onKeyChange", event, pressed, event.keyCode, event.shiftKey, event.ctrlKey, event.altKey, event.metaKey) |
| 82 | + |
| 83 | + // update this.keyCodes |
| 84 | + var keyCode = event.keyCode; |
| 85 | + this.keyCodes[keyCode] = pressed; |
| 86 | + |
| 87 | + // update this.modifiers |
| 88 | + this.modifiers['shift']= event.shiftKey; |
| 89 | + this.modifiers['ctrl'] = event.ctrlKey; |
| 90 | + this.modifiers['alt'] = event.altKey; |
| 91 | + this.modifiers['meta'] = event.metaKey; |
| 92 | +} |
| 93 | + |
| 94 | +/** |
| 95 | + * query keyboard state to know if a key is pressed of not |
| 96 | + * |
| 97 | + * @param {String} keyDesc the description of the key. format : modifiers+key e.g shift+A |
| 98 | + * @returns {Boolean} true if the key is pressed, false otherwise |
| 99 | +*/ |
| 100 | +THREEx.KeyboardState.prototype.pressed = function(keyDesc) |
| 101 | +{ |
| 102 | + var keys = keyDesc.split("+"); |
| 103 | + for(var i = 0; i < keys.length; i++){ |
| 104 | + var key = keys[i]; |
| 105 | + var pressed; |
| 106 | + if( THREEx.KeyboardState.MODIFIERS.indexOf( key ) !== -1 ){ |
| 107 | + pressed = this.modifiers[key]; |
| 108 | + }else if( Object.keys(THREEx.KeyboardState.ALIAS).indexOf( key ) != -1 ){ |
| 109 | + pressed = this.keyCodes[ THREEx.KeyboardState.ALIAS[key] ]; |
| 110 | + }else { |
| 111 | + pressed = this.keyCodes[key.toUpperCase().charCodeAt(0)] |
| 112 | + } |
| 113 | + if( !pressed) return false; |
| 114 | + }; |
| 115 | + return true; |
| 116 | +} |
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