PlayerController Class
Currently, when your player clicks the Build button, it enables the TurretSpawner which, in turn allows them to click on tiles to spawn multiple turrets. Next, you will create a PlayerController class that will track a Gold resource for the player that limits their ability to place turrets. When the player builds a turret, it will reduce the player's Gold.
Practice: Create a PlayerController Class and GameObject
- Create a new
MonoBehaviournamedPlayerController - Add an
int GoldProperty - In your scene, add a new GameObject that has a
PlayerControllercomponent . - Set the
Goldproperty in the Inspector to200
When you have finished, your scene should look similar to the image below:
Add a Text Label for Gold
To help the player know how much gold they have, add a Text Label to your Canvas
- In the Hierarchy, right click on your Canvas
- Select Create > UI > Text - TextMeshPro
Practice: Anchor the Gold Label to the Top Left Corner
Recall how you anchored your Build button to the bottom left corner of the screen (see: 16 - Placing Turrets > UI Pivots). You can do the same thing with any UI component. Additionally, if you hold Shift and Alt while selecting a pivot, it will move your UI component to that position.
- Select your
Gold Label - In the Inspector click the Pivot icon on the Rect Transform
- Press and hold Shift + Alt
- Click the Top Left Corner pivot icon
- Observe that the text moves to the top left corner, additionally the anchor and pivot values update.
- Adjust the
Pos XandPos Yvalues slightly to keep the text from touching the edge of the screen.
- Update the default text to display "Gold: 0"
Updating the Gold Label
Now that you have a Gold Label, you can make it reference your PlayerController and update the text component to display the current amount of Gold the player has available.
Create a GoldLabelController MonoBehaviour
- Create a new
MonoBehaviournamedGoldLabelController - Add a
PlayerController Controllerproperty - Add a
TextMeshProGUI Labelproperty - Add an
Update()method: - Set
Label.textto displayController.Gold
Attach the GoldLabelController component
- Add a
GoldLabelControllercomponent to yourGoldLabel - Connect the
PlayerControllerandLabelproperties in the Inspector- Note:
Labelshould reference the Gold Label (self)
- Note:
- Enter Play Mode to confirm the label updates
- Adjust the
PlayerController's Gold property to observe the change
Spending Gold to Spawn
Practice: Reference PlayerController in TurretSpawner
To be able to check if we can spawn a turret, the TurretSpawner must check if the player has enough gold.
- Add a
PlayerController Controllerproperty to theTurretSpawnerMonoBehaviour - In the Inspector connect the PlayerController to the TurretSpawner
When you have finished, your inspector should look similar to the image below:
Challenge: Add a CanSpawn Method to TurretSpawner
- Add a
bool CanSpawn(TileController tileController)method to theTurretSpawnerMonoBehaviour: - The method returns
falseif thetileControlleris occupied - The method returns
falseif theControllerdoes not have at least 50 gold - Otherwise, the method returns
true - Update the
SpawnTurretmethod to useCanSpawnto determine if a turret can be spawned - Update the
SpawnTurretmethod to reduceController.Goldby 50 - Enter Play Mode to test your spawner
- You should only be able to place 4 turrets
- After placing each turret, you should observe that the gold decreases
When you have finished, you should see something similar to the video below:
Interaction Hints
Currently, your player does not receive much information about what the result of clicking on a tile will be. This can be both confusing and frustrating. How were they supposed to know the turret was going to cost 50 gold! Maybe they didn't see that they were out of gold and don't understand why clicking is not placing a turret. To help create a better user experience, you will add in a text label that will display information to the player.
Practice: Add an Information Label to your Canvas
- Add a Text - TextMeshPro to your Canvas (Info Label)
- Change the default text to "Player Interaction Info Label"
- Position and resize the text on the screen to your liking
- Note: In the preview project, the information label will be on the bottom center of the screen
When you have finished, your game view should look like the video below:
Practice: Add InfoLabel to PlayerController
- Add a
TextMeshProGUI InfoLabelto yourPlayerControllerMonoBehaviour - Add a
Start()method toPlayerController - Set
InfoLabel.textto display "Click Build to Place a Turret" - Connect the InfoLabel in the Inspector
- Enter Play Mode to test that the InfoLabel updates when the game starts
When you have finished, your scene should look similar to the video below:
Disable Raycast Target
By default, Text labels intercept click events of a mouse. This can be useful if you want to detect if a mouse is hovering over a label. However, this can be problematic if your label is blocking a button or your game scene. This can be disabled in the Extra Settings section of the TextMeshPro - Text(UI) component.
- Disable Raycast Target in your Info Label / Gold Label to prevent them from blocking your buttons / turret placements.
TurretSpawner.ShowInfo(TileController)
- Add a
ShowInfo(TileController)method toTurretSpawner: - If the
tileController.IsOccupieddisplay "Cannot build here" - If the
Controller.Gold < 50display "<color=red>Not enough gold" - else display "50 Gold - Place Turret"
Challenge: Display Info to the Player
- Update your
TurretSpanwerMonoBehaviour in the following ways - When enabled, display "Select a Tile"
- Add a listener such that
ShowInfois called when the cursor enters a tile - Add a listener such that "Select a Tile" is displayed when the cursor exits a tile
- After a turret is placed, disable the TurretSpawner
- Be sure to remove any listeners when TurretSpawner is disabled
- When disabled, display "Click Build to Place a Turret"
- Enter Play Mode to test your changes
When you have finished, your game should behave similar to the scene below:
What's Next?
Now that your player can use gold to build turrets, it is now time to create a way for the player to gain gold. In the next lesson, you will create a new building that continuously generates gold for the player.