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'use strict';
/*
Serpentity is a simple entity framework inspired by Ash.
Usage:
let Serpentity = require('serpentity');
## Instantiating an engine
let engine = Serpentity();
Add entities or systems, systems are added with a priority (the smaller
the number, the earlier it will be called):
engine.addEntity(entityFactory());
engine.addSystem(new GameSystem(), priority);
Update all systems:
engine.update(dt);
Remove entities or systems:
engine.removeEntity(entityReference);
engine.removeSystem(systemReference);
## Creating Entities
Entities are the basic object of Serpentity, and they do nothing.
let entity = new Serpentity.Entity();
All the behavior is added through components
## Creating Components
Components define data that we can add to an entity. This data will
eventually be consumed by "Systems"
let PositionComponent = class PositionComponent extends Serpentity.Component {
constructor (config) {
this.x = 0;
this.y = 0;
super(config);
}
};
You can add components to entities by using the add method:
entity.addComponent(new PositionComponent());
Systems can refer to entities by requesting nodes.
## Working with Nodes
Nodes are sets of components that you define, so your system can require
entities that always follow the API defined in the node.
let MovementNode = class MovementNode extends Serpentity.Node;
MovementNode.position = PositionComponent;
MovementNode.motion = MotionComponent;
You can then request an array of all the nodes representing entities
that comply with that API
engine.getNodes(MovementNode);
## Creating Systems
Systems are called on every update, and they use components through nodes.
let TestSystem = class TestSystem extends Serpentity.System {
added (engine){
this.nodeList = engine.getNodes(MovementNode);
},
removed (engine){
this.nodeList = undefined;
}
update (dt){
let node;
for (node of this.nodeList) {
console.log(`Current position is: ${node.position.x},${node.position.y}`);
}
}
};
## That's it
Just run `engine.update(dt)` in your game loop :D
*/
var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
var Serpentity = function () {
function Serpentity(config) {
_classCallCheck(this, Serpentity);
this.systems = [];
this.entities = [];
this._nodeCollections = [];
this._nodeCollectionKeys = [];
Object.assign(this, config || {});
}
/*
* Adds a system to the engine, so its update method will be called
* with the others. Triggers added hook.
*
* returns true if added succesfully, false if already added
*/
_createClass(Serpentity, [{
key: 'addSystem',
value: function addSystem(system, priority) {
var lastIndex = void 0,
found = void 0;
if (this.systems.indexOf(system) >= 0) {
return false;
}
system.priority = priority;
found = false;
lastIndex = 0;
this.systems.some(function findPriority(existingSystem, i) {
lastIndex = i;
if (existingSystem.priority >= system.priority) {
found = true;
return true;
}
});
if (!found) {
lastIndex += 1;
}
this.systems.splice(lastIndex, 0, system);
system.added(this);
return true;
}
/*
* Removes a system from the engine, so its update method will no
* longer will be called. Triggers the removed hook.
*
* returns true if removed succesfully, false if already added
*/
}, {
key: 'removeSystem',
value: function removeSystem(system) {
var position = void 0;
position = this.systems.indexOf(system);
if (position >= 0) {
this.systems[position].removed(this);
this.systems.splice(position, 1);
return true;
}
return false;
}
/*
* Adds an entity to the engine, adds to existing node collections
*
* returns true if added, false if already there
*/
}, {
key: 'addEntity',
value: function addEntity(entity) {
if (this.entities.indexOf(entity) >= 0) {
return false;
}
this.entities.push(entity);
this._nodeCollections.forEach(function (collection) {
collection.add(entity);
});
return true;
}
/*
* Removes entity from system, removing from all node collections
*
* returns true if removed, false if not present
*/
}, {
key: 'removeEntity',
value: function removeEntity(entity) {
var position = void 0;
position = this.entities.indexOf(entity);
if (position >= 0) {
this._nodeCollections.forEach(function (collection) {
collection.remove(entity);
});
this.entities.splice(position, 1);
return true;
}
return false;
}
/*
* Given a Node Class, retrieves a list of all the nodes for each
* applicable entity.
*/
}, {
key: 'getNodes',
value: function getNodes(nodeType) {
var position = void 0,
nodeCollection = void 0;
position = this._nodeCollectionKeys.indexOf(nodeType);
if (position >= 0) {
return this._nodeCollections[position].nodes;
}
nodeCollection = new Serpentity.NodeCollection({
type: nodeType
});
this._nodeCollectionKeys.push(nodeType);
this._nodeCollections.push(nodeCollection);
this.entities.forEach(function (entity) {
nodeCollection.add(entity);
});
return nodeCollection.nodes;
}
/*
* Calls update for every loaded system.
*/
}, {
key: 'update',
value: function update(dt) {
this.systems.forEach(function (system) {
system.update(dt);
});
}
}]);
return Serpentity;
}();
// Add namespaced objects.
if (typeof module !== 'undefined' && undefined.module !== module) {
Serpentity.Component = require('./serpentity/component.js');
Serpentity.Entity = require('./serpentity/entity.js');
Serpentity.Node = require('./serpentity/node.js');
Serpentity.NodeCollection = require('./serpentity/node_collection.js');
Serpentity.System = require('./serpentity/system.js');
module.exports = Serpentity;
}
'use strict';
/* global Serpentity */
/*
* The entity gives the entity framework its name. It exists only
* to hold components.
*/
var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
var Entity = function () {
function Entity(config) {
_classCallCheck(this, Entity);
this._componentKeys = [];
this._components = [];
Object.assign(this, config || {});
}
/*
* Adds a component to the entity.
*
* returns true if added, false if already present
*/
_createClass(Entity, [{
key: 'addComponent',
value: function addComponent(component) {
if (this._componentKeys.indexOf(component.constructor) >= 0) {
return false;
}
this._componentKeys.push(component.constructor);
this._components.push(component);
return true;
}
/*
* returns true if component is included, false otherwise
*/
}, {
key: 'hasComponent',
value: function hasComponent(componentClass) {
if (this._componentKeys.indexOf(componentClass) >= 0) {
return true;
}
return false;
}
/*
* returns the component associated with that key
*/
}, {
key: 'getComponent',
value: function getComponent(componentClass) {
var position = this._componentKeys.indexOf(componentClass);
if (position >= 0) {
return this._components[position];
}
}
}]);
return Entity;
}();
if (typeof module !== 'undefined' && undefined.module !== module) {
module.exports = Entity;
} else {
Serpentity.Entity = Entity;
}
'use strict';
/* global Serpentity */
/*
* A node describes a set of components in order to describe entities
* that include them.
*/
var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
var Node = function () {
_createClass(Node, null, [{
key: 'matches',
/*
* Returns true if the given entity matches the defined protocol,
* false otherwise
*/
value: function matches(entity) {
var types = this.types;
for (var typeName in types) {
if (types.hasOwnProperty(typeName)) {
var matched = false;
var type = types[typeName];
if (entity.hasComponent(type)) {
matched = true;
}
if (!matched) {
return false;
}
}
}
return true;
}
}]);
function Node(config) {
_classCallCheck(this, Node);
this.types = {};
Object.assign(this, config || {});
}
return Node;
}();
if (typeof module !== 'undefined' && undefined.module !== module) {
module.exports = Node;
} else {
Serpentity.Node = Node;
}
'use strict';
/* global Serpentity */
/*
* Node Collections contain nodes, in order to keep the lists of nodes
* that belong to each type.
*
* It has a type which is the class name of the node, and an array of
* instances of that class.
*/
var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
var NodeCollection = function () {
function NodeCollection(config) {
_classCallCheck(this, NodeCollection);
this.nodes = [];
this.type = null;
Object.assign(this, config || {});
}
/*
* Creates a node for an entity if it matches, and adds it to the
* node list.
*
* Returns true if added, false otherwise.
*/
_createClass(NodeCollection, [{
key: 'add',
value: function add(entity) {
if (this.type.matches(entity) && !this._entityExists(entity)) {
var node = new this.type({});
var types = this.type.types;
node.entity = entity;
for (var typeName in types) {
if (types.hasOwnProperty(typeName)) {
node[typeName] = entity.getComponent(types[typeName]);
}
}
this.nodes.push(node);
return true;
}
return false;
}
/*
* Removes an entity by removing its related node from the list of nodes
*
* returns true if it was removed, false otherwise.
*/
}, {
key: 'remove',
value: function remove(entity) {
var found = -1;
this.nodes.forEach(function (node, i) {
if (node.entity === entity) {
found = i;
}
});
if (found >= 0) {
this.nodes.splice(found, 1);
return true;
}
return false;
}
/*
* Checks whether we already have nodes for this entity.
*/
}, {
key: '_entityExists',
value: function _entityExists(entity) {
var found = false;
var _iteratorNormalCompletion = true;
var _didIteratorError = false;
var _iteratorError = undefined;
try {
for (var _iterator = this.nodes[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
var node = _step.value;
if (node.entity === entity) {
found = true;
}
}
} catch (err) {
_didIteratorError = true;
_iteratorError = err;
} finally {
try {
if (!_iteratorNormalCompletion && _iterator.return) {
_iterator.return();
}
} finally {
if (_didIteratorError) {
throw _iteratorError;
}
}
}
return found;
}
}]);
return NodeCollection;
}();
if (typeof module !== 'undefined' && undefined.module !== module) {
module.exports = NodeCollection;
} else {
Serpentity.NodeCollection = NodeCollection;
}
'use strict';
/* global Serpentity */
/*
* Components store data. Nothing to say here really, just
* inherit and add a prototype, or don't even inherit, see?
* It's just an empty class, so what I'm trying to say is your
* components can be any class whatsoever.
*/
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
var Component = function Component(config) {
_classCallCheck(this, Component);
Object.assign(this, config || {});
};
if (typeof module !== 'undefined' && undefined.module !== module) {
module.exports = Component;
} else {
Serpentity.Component = Component;
}
'use strict';
/* global Serpentity */
/*
* Systems contain most of the logic, and work with nodes in order to
* act and change their values.
*
* You usually want to inherit from this class and override the
* three methods. They are shown here to document the interface.
*/
var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
var System = function () {
function System() {
_classCallCheck(this, System);
}
_createClass(System, [{
key: 'added',
/*
* This will be run when the system is added to the engine
*/
value: function added() {}
// Override with added(engine)
// Receives an instance of the serpentity engine
/*
* This will be run when the system is removed from the engine
*/
}, {
key: 'removed',
value: function removed() {}
// Override with removed(engine)
// Receives an instance of the serpentity engine
/*
* This will run every time the engine's update method is called
*/
}, {
key: 'update',
value: function update() {
// Override with update(dt)
// Receives a delta of the time
}
}]);
return System;
}();
if (typeof module !== 'undefined' && undefined.module !== module) {
module.exports = System;
} else {
Serpentity.System = System;
}
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