silphius/app/ecs-systems/plant-growth.js

import {System} from '@/ecs/index.js';

export default class PlantGrowth extends System {

  frequency = 1;

  static queries() {
    return {
      default: ['Plant'],
    };
  }

  tick(elapsed) {
    const variance = Math.random() * 0.4 + 0.8
    for (const {Plant} of this.select('default')) {
      if (65535 === Plant.growth || !Plant.mayGrow()) {
        continue;
      }
      const stage = Math.floor(Plant.stage);
      const growthFactor = (((Plant.growthFactor + 1) / 256) * 0.4 + 0.8) * variance
      Plant.growth = Math.min(
        Plant.growth + ((growthFactor * elapsed) / Plant.stages[stage]) * 65535,
        65535,
      );
      if (65535 === Plant.growth) {
        Plant.grow();
      }
    }
  }

}