1. Player preferences, Loading Scenes, Activating and Enabling
Unity Notes
Player preferences, Loading Scenes, Activating and Enabling

2. Review Camera size is ½ screen height and width.
Images often have 100:1 pixel to unit ratio
In 2D, z value is used for layering
Object positions are world space for parents, object space for children
Fields can be serialized rather than public
Attaching BoxColliders registers objects for collision events

3. Player Preferences File stored on disk by unity
Keep player preferences between plays
It’s really a hashtable

4. Using preferences
bool PlayerPrefs.HasKey(String key) void PlayerPrefs.SetInt(String key, int value) void PlayerPrefs.SetFloat(String key, float value) void PlayerPrefs.SetString(String key, String value) int PlayerPrefs.GetInt(String key) etc…

5. Don’t duplicate data
Usually a bad idea to store things in 2 different places – why?
Don’t re-keep data in local variable without a good reason

6. Loading Scenes
need using statement: using UnityEngine.SceneManagement;
SceneManager is static object void SceneManager.LoadScene(String sceneName);

7. Runtime activation
GameObjects can be activated and de-activated in code: gameObject.SetActive(false);
When might you want to do this?
You can check status as well: bool isActive = gameObject.activeSelf;

8. Runtime enabling
Maybe you don’t want the whole object de-activated, but you do want to enable or disable one component of the object: myComponent = GetComponent<Whatever>(); myComponent.enabled = true;