Tile Costs for Pathfinding

This example shows how tile costs can be considered for pathfinding. The liana has a tile cost of 4 when climbing up (the tiles have the property ge_cost_down = 4). Characters have been set up to slow down by the factor of the tile costs. Try to climb up the liana to observe this.

You can turn considerCosts([1], [2], [3]) on and off for the pathfinding of the NPC and observe how it will take the higher tile cost of the liana into account.

NOTE: considerCosts does only work with A*

Code

🔗 See full code on GitHub

📖 How to execute examples locally

code.jsindex.html../../js/examplePhaserConfig.js../styles.css

const game = new Phaser.Game(config(preload, create, update));
let considerCosts = false;
let gridEngine;

function preload() {
  this.load.image("tiles", "../../assets/tf_jungle_tileset.png");
  this.load.tilemapTiledJSON(
    "jungle",
    "../../assets/tile-costs.json"
  );

  this.load.spritesheet("player", "../../assets/characters.png", {
    frameWidth: 52,
    frameHeight: 72,
  });
}

function create() {
  const cloudCityTilemap = this.make.tilemap({ key: "jungle" });
  cloudCityTilemap.addTilesetImage("jungle", "tiles");
  for (let i = 0; i < cloudCityTilemap.layers.length; i++) {
    const layer = cloudCityTilemap.createLayer(i, "jungle", 0, 0);
    layer.scale = 3;
  }
  const playerSprite = this.add.sprite(0, 0, "player");
  playerSprite.scale = 1.5;
  const npcSprite = this.add.sprite(0, 0, "player");
  npcSprite.scale = 1.5;
  this.cameras.main.startFollow(playerSprite, true);
  this.cameras.main.setFollowOffset(
    -playerSprite.width,
    -playerSprite.height
  );

  const gridEngineConfig = {
    characters: [
      {
        id: "player",
        sprite: playerSprite,
        walkingAnimationMapping: 6,
        startPosition: { x: 18, y: 14 },
      },
      {
        id: "npc",
        sprite: npcSprite,
        walkingAnimationMapping: 2,
        startPosition: { x: 15, y: 15 },
      },
    ],
  };

  this.gridEngine.create(cloudCityTilemap, gridEngineConfig);
  this.gridEngine.positionChangeStarted().subscribe(({ charId, enterTile, enterLayer, exitTile }) => {
    const dir = GridEngineImports.directionFromPos(enterTile, exitTile);
    const cost = this.gridEngine.getTileCost(enterTile, enterLayer, dir);
    this.gridEngine.setSpeed(charId, 3 / cost);
  });
  gridEngine = this.gridEngine;

  const triangleArgs = [0, 0, 50, 0, 24, 50, 0xffffff];
  const arrow = this.add.triangle(
    16 * 48 + 24,
    9 * 48 + 24,
    ...triangleArgs
  );
  this.tweens.add({
    targets: [arrow],
    alpha: 0.2,
    yoyo: true,
    repeat: -1,
    ease: "Sine.easeInOut",
  });
  settingsToConf();
}

function update() {
  const cursors = this.input.keyboard.createCursorKeys();
  if (cursors.left.isDown) {
    this.gridEngine.move("player", "left");
  } else if (cursors.right.isDown) {
    this.gridEngine.move("player", "right");
  } else if (cursors.up.isDown) {
    this.gridEngine.move("player", "up");
  } else if (cursors.down.isDown) {
    this.gridEngine.move("player", "down");
  }
}

function startPathfinding() {
  considerCosts = !!document.getElementById("consider-costs").checked;
  settingsToConf();
  gridEngine.setPosition("npc", { x: 15, y: 15 });
  gridEngine.moveTo("npc", { x: 16, y: 5 }, {
    algorithm: "A_STAR",
    considerCosts
  });
}

function settingsToConf() {
  let text = '';
  text = JSON.stringify({
    algorithm: "A_STAR",
    considerCosts,
  }, null, 2);
  document.getElementById(
    "json-config"
  ).innerHTML = `<pre>${text}</pre>`;
}

html

<!doctype html>
<html>
  <head>
    <link rel="stylesheet" href="../styles.css" />
    <script src="../../js/phaser-3.80.1.min.js"></script>
    <script src="../../js/grid-engine-2.44.3.min.js"></script>
    <script src="../../js/examplePhaserConfig.js"></script>
    <script src="code.js"></script>
    <meta name="color-scheme" content="dark light" />
  </head>
  <body>
    <div class="settings">
      <h2>Settings:</h2>

      <div class="wait-timeout-group">
        <input
          type="checkbox"
          id="consider-costs"
          name="consider-costs"
          value="true"
        />
        <label for="consider-costs">considerCosts</label>
      </div>

      <button class="apply" onclick="startPathfinding()">
        Start pathfinding
      </button>

      <h3>MoveToConfig:</h3>
      <div id="json-config"></div>
    </div>
    <div id="game" scrolling="no"></div>
  </body>
</html>

function config(preload, create, update) {
  return {
    title: "GridEngineExample",
    render: {
      antialias: false,
    },
    type: Phaser.AUTO,
    plugins: {
      scene: [
        {
          key: "gridEngine",
          plugin: GridEngine,
          mapping: "gridEngine",
        },
      ],
    },
    scale: {
      width: 700,
      height: 528,
    },
    scene: {
      preload: preload,
      create: create,
      update: update,
    },
    parent: "game",
    backgroundColor: "#48C4F8",
    input: {
      mouse: {
        preventDefaultWheel: false
      },
      touch: {
        capture: false
      }
    }
  };
}

css

body {
  margin: 0;
  padding: 0;
  background: #1e1e20;
  font-family: Inter,-apple-system,system-ui,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  color: #cacaca;
}

.settings {
  margin-top: 20px;
  display: flex;
  flex-direction: column;
  /* border: 1px solid white; */
  background: #282828;
  margin-bottom: 20px;
  width: 640px;
  padding: 0 30px;
}

label {
  font-weight: bold;
  margin-top: 30px;
  margin-bottom: 10px;
}

select {
  width: 100px;
}

input {
  width: 100px;
}

button {
  width: 120px;
  margin-top: 30px;
  margin-bottom: 20px;
}

.wait-timeout-group {
  display: flex;
  align-items: center;
  justify-content: flex-start;
}

.wait-timeout-group input {
  width: auto;
  margin-right: 10px;
}

.wait-timeout-group label {
  margin:0;
}

#json-config {
  margin-bottom: 10px;
}

#json-config pre {
  font-family: "Consolas", monospace;
}

.disabled {
  display: none;
}

Tile Costs for Pathfinding ​

Code ​

Tile Costs for Pathfinding

Code