Save slot management in Unity - Step-by-Step Execution

Concept Flow - Save slot management

Start Game

↓

Display Save Slots

↓

Player Selects Slot

↓

Check Slot Exists?

No→Create New Save

↓

Save Data Initialized

↓

Load Save Data

↓

Player Plays Game

↓

Player Plays Game

↓

Player Saves Progress

↓

Player Saves Progress

↓

Update Save Slot Data

↓

Return to Save Slots or Exit

The game starts by showing save slots. The player picks one. If it exists, load it; if not, create new. Player plays and saves, updating the slot.

Execution Sample

Unity

void SaveGame(int slot) {
  if (SaveExists(slot)) {
    LoadSave(slot);
  } else {
    CreateNewSave(slot);
  }
  // Player plays and saves
  SaveData(slot);
}

This code checks if a save slot exists, loads or creates it, then saves player data.

Execution Table

Step	Action	Slot	Condition	Result	Output
1	Player selects slot	1	N/A	Slot 1 selected	Display slot status
2	Check if save exists	1	SaveExists(1)?	False	Create new save
3	Create new save	1	N/A	New save created	Initialize data
4	Player plays game	1	N/A	Game running	Player progress ongoing
5	Player saves progress	1	N/A	SaveData(1) called	Data saved to slot 1
6	Player selects slot	2	N/A	Slot 2 selected	Display slot status
7	Check if save exists	2	SaveExists(2)?	True	Load save data
8	Load save data	2	N/A	Data loaded	Player continues from save
9	Player plays game	2	N/A	Game running	Player progress ongoing
10	Player saves progress	2	N/A	SaveData(2) called	Data saved to slot 2
11	Exit	N/A	N/A	End of session	Game closes or returns to menu

💡 Execution stops when player exits or returns to main menu.

Variable Tracker

Variable	Start	After Step 2	After Step 3	After Step 5	After Step 7	After Step 8	After Step 10	Final
slot	N/A	1	1	1	2	2	2	N/A
SaveExists(slot)	N/A	False	False	True	True	True	True	N/A
SaveData(slot)	N/A	N/A	N/A	Saved	N/A	N/A	Saved	N/A
GameState	Empty	Empty	Initialized	Playing	Loaded	Playing	Saved	N/A

Key Moments - 3 Insights

Why do we check if a save slot exists before loading?

Because if the slot doesn't exist (see step 2 in execution_table), we must create a new save to avoid errors.

What happens if the player selects a slot with existing data?

The game loads the saved data (step 7 and 8), so the player continues from where they left off.

When is the save data actually written to the slot?

After the player finishes playing and chooses to save (steps 5 and 10), the data is saved to the slot.

Visual Quiz - 3 Questions

Look at the execution table, what is the result of SaveExists(1) at step 2?

A Error

B False

C True

D Not checked

💡 Hint

Check the 'Condition' and 'Result' columns at step 2 in the execution_table.

At which step does the game create a new save slot?

A Step 1

B Step 7

C Step 3

D Step 10

💡 Hint

Look for the action 'Create new save' in the execution_table.

If SaveExists(2) was false, how would the execution_table change at step 7?

A It would create a new save

B It would load save data

C It would skip saving

D It would exit the game

💡 Hint

Compare step 2 and 7 actions for when SaveExists is false.

Concept Snapshot

Save Slot Management in Unity:
- Show save slots to player
- On slot select, check if save exists
- If yes, load save data
- If no, create new save
- Player plays and saves progress
- Save updates slot data
- Repeat or exit game

Full Transcript

This visual execution shows how save slot management works in Unity. The game starts by displaying save slots. When the player selects a slot, the program checks if a save exists. If not, it creates a new save. The player then plays the game and can save progress, which updates the save slot data. This cycle repeats for different slots until the player exits or returns to the main menu.