Skip to content

🎮 VR Project Save System Documentation

This document describes the Save System architecture used in the VR Capstone project.
The system is built using Unreal Engine 5, and its core components include:

  • VRGameMode
  • BP_GameInstance
  • SG_LocalGameSetting (local save)
  • SG_SaveData (per-user save)
  • Login / Save UI widgets

Overall Flow

When the game starts:

  1. VRGameMode is the first blueprint to run.
  2. Inside BeginPlay, VRGameMode:
  3. Casts to BP_GameInstance
  4. Calls initialization logic in GameInstance
  5. Loads the last used user ID (LastUserID) from SG_LocalGameSetting
  6. Automatically loads the correct SG_SaveData
  7. During gameplay:
  8. Scenario progress is managed through functions in BP_GameInstance
  9. Progress is written into SG_SaveData

Save File Types

The system uses two SaveGame files:

  • SG_LocalGameSetting
  • SG_SaveData

SG_LocalGameSetting

SG_LocalGameSetting stores local settings related to the last used save.

Stored Field

Field Type Description
LastUserID STRING Stored in the format "UserID_SessionID"

LastUserID Format

Examples

  • 123456_0001
  • 842193_0002
  • 554400_0010

Purpose

  • During game startup, LastUserID is loaded.
  • The Login UI automatically parses this string and fills:
  • ASUID → extracted before the underscore
  • SessionID → extracted after the underscore
  • This allows the player to continue immediately without retyping their ID.

SG_SaveData

Each UserID + SessionID combination generates a unique save file.

Fields

Field Type Description
ASUID INT Student/user ID
StudentName STRING Player name
SessionID INT The session (save slot) number
ScenarioProgress Array of Struct Stores progress for all scenarios

ScenarioProgress Struct

Field Type Description
CharacterName STRING Scenario character
ScenarioNumber INT Scenario ID number
Progress FLOAT Scenario progress value
LastSaveTime STRING / DateTime Timestamp of the last save

BP_GameInstance Functions

BP_GameInstance serves as the central controller for save management.

Initial()

Executed during VRGameMode → BeginPlay.

Responsibilities

  • Load or create SG_LocalGameSetting
  • Read LastUserID
  • Automatically load the corresponding SG_SaveData
  • Prepare the login screen with auto-filled values

Login(ASUID, StudentName, SessionID)

Triggered by the Login UI.

Login Flow

  1. The user enters:
  2. ASUID
  3. SessionID
  4. User presses Login.
  5. The system checks if a save file exists:
  6. If save exists → Load SG_SaveData
  7. If no save exists → Show a warning popup:
    • “No save data found for this ID and Session. Please create a new save.”

New Save Flow

  • User presses New Save.
  • WB_Save_New widget appears.
  • User enters:
  • ASUID
  • StudentName
  • SessionID
  • Upon pressing Create:
  • A new SG_SaveData is generated.
  • SG_LocalGameSetting.LastUserID is updated to:

ASUID + "_" + SessionID

  • The new save file is loaded and the game continues.

Save / Load UI Widgets

Two widgets support the login and save creation process.

WB_Save_Main

  • Displays existing save sessions
  • Automatically fills fields using LastUserID
  • Allows user to:
  • Continue an existing save
  • Open the New Save creation window

WB_Save_New

Used to create a brand-new save file.

User Inputs

  • ASUID
  • StudentName
  • SessionID

Features

  • VR Virtual Keyboard support
  • Default SessionID = 0001
  • Generates a new save file and updates SG_LocalGameSetting

SessionID Policy

A single user can create multiple independent save files using different SessionIDs.

Example

ASUID SessionID Meaning
123456 0001 Practice session
123456 0002 Assessment session
987654 0001 Another user

Important

If the user forgets their SessionID, the save file cannot be recovered through normal gameplay.
They must write it down or remember it.

Map Transition Behavior

When changing maps:

  1. BP_GameInstance retains current ASUID + SessionID
  2. New map's GameMode casts to BP_GameInstance
  3. Scenario progress is retrieved with GetScenarioProgress()
  4. Spawn, UI, and skipped sequences depend on progress

Future Improvements (Optional)

  • Auto-save checkpoints
  • Administrator session recovery tools
  • Save sorting and tagging
  • Cloud or server-side save backups

End of Document