git.r.bdr.sh - rbdr/sumo/blob - lib/systems/dash.js

   1 import { System } from '@serpentity/serpentity';
   2
   3 const internals = {
   4   kForce: 20
   5 };
   6
   7 import DasherNode from '../nodes/dasher';
   8
   9 /**
  10  * Applies a dash as a force on an entity. Locks it until the button is released
  11  * and a cooldown period has passed
  12  *
  13  * @extends {external:Serpentity.System}
  14  * @class DashSystem
  15  * @param {object} config a configuration object to extend.
  16  */
  17 export default class DashSystem extends System {
  18
  19   constructor(config = {}) {
  20
  21     super();
  22
  23     /**
  24      * The node collection of dashers
  25      *
  26      * @property {external:Serpentity.NodeCollection} dashers
  27      * @instance
  28      * @memberof DashSystem
  29      */
  30     this.dashers = null;
  31   }
  32
  33   /**
  34    * Initializes system when added. Requests dasher nodes
  35    *
  36    * @function added
  37    * @memberof DashSystem
  38    * @instance
  39    * @param {external:Serpentity.Engine} engine the serpentity engine to
  40    * which we are getting added
  41    */
  42   added(engine) {
  43
  44     this.dashers = engine.getNodes(DasherNode);
  45   }
  46
  47   /**
  48    * Clears system resources when removed.
  49    *
  50    * @function removed
  51    * @instance
  52    * @memberof DashSystem
  53    */
  54   removed() {
  55
  56     this.dashers = null;
  57   }
  58
  59   /**
  60    * Runs on every update of the loop. Triggers dash and manages cooldown
  61    *
  62    * @function update
  63    * @instance
  64    * @param {Number} currentFrameDuration the duration of the current
  65    * frame
  66    * @memberof DashSystem
  67    */
  68   update(currentFrameDuration) {
  69
  70     for (const dasher of this.dashers) {
  71
  72       const dash = dasher.dash;
  73
  74       if (dash.dashing && !dash.locked) {
  75         this._dash(dasher);
  76       }
  77
  78       if (!dash.dashing && dash.locked && dash.currentCooldown >= dash.cooldown) {
  79         this._unlock(dasher);
  80       }
  81
  82       if (dash.locked) {
  83         dash.currentCooldown += currentFrameDuration;
  84       }
  85
  86       dash.dashing = 0;
  87     }
  88   }
  89
  90   // Executes the dash action
  91
  92   _dash(dasher) {
  93
  94     const dash = dasher.dash;
  95     const force = dasher.force;
  96
  97     const angle = force.lastAngle || 0;
  98     dash.locked = true;
  99     dash.currentCooldown = 0;
 100
 101     const xComponent = internals.kForce * Math.cos(angle);
 102     const yComponent = internals.kForce * Math.sin(angle);
 103
 104     force.x += xComponent;
 105     force.y += yComponent;
 106   }
 107
 108   // Executes the unlock action
 109
 110   _unlock(dasher) {
 111
 112     dasher.dash.locked = false;
 113   }
 114 };
 115
 116