DragDrawer System

Drag-to-Open Drawer System

Unity 2022.3 LTS | URP & Built-in Compatible

A lightweight, realistic, and plug-and-play drag-based drawer interaction system designed for first-person Unity projects.

This system allows players to physically drag drawers open and closed using mouse movement, creating natural and immersive interactions commonly seen in modern FPS and simulation games.

The package is built with clean code, no external dependencies, and focuses on simplicity, performance, and Asset Store–friendly structure.

Core Concept

• Uses a center-screen raycast to detect interactable drawers
• When the player looks at a drawer within range, a minimal interaction UI appears
• Pressing "E" and holding the left mouse button and dragging vertically moves the drawer along its local Z axis
• Drawer movement is fully clamped to prevent over-extension
• Audio feedback plays only when the drawer fully opens or closes
• A single shared UI instance is used to prevent flickering when looking between multiple drawers

Key Features

• Drag-based drawer opening & closing (mouse-driven)
• Realistic, physics-free drawer movement
• Distance-based interaction detection
• Center-screen raycast interaction
• Minimal Interact UI (Image + Text)
• Included lightweight FPS controller
• Optional open / close audio support
• One global UI controller for all drawers
• No ScriptableObjects
• No Cinemachine
• No third-party packages
• Clean, readable, Asset Store–safe code

Input System Requirement (Important)

This asset requires BOTH Unity Input Systems to be enabled

The system uses:

• (for Input.GetAxis, Mouse X / Mouse Y, mouse buttons)Old Input Manager
• (required for compatibility with modern Unity setups and controllers)New Input System

You MUST set:

Project Settings → Player → Active Input Handling

Both

If only one input system is enabled, the drawer dragging and FPS controls will not work correctly.

TextMeshPro Requirement (Important)

TextMeshPro is REQUIRED

The interaction UI uses TextMeshPro for clean, sharp instruction text.

Make sure TextMeshPro is installed:

• Window → TextMeshPro → Import TMP Essential Resources

Without TextMeshPro, the Interact UI text will not render.

Included Scripts

DragDrawer

• Handles drawer dragging logic
• Controls open / close limits
• Manages audio playback
• Performs raycast interaction detection
• Communicates with the Interact UI
• Ensures only one drawer controls the UI at a time

InteractUI

• Centralized UI controller (singleton)
• Handles interaction image + TextMeshPro text
• Automatically shows/hides based on raycast detection

SimpleFpsController

• Lightweight FPS controller
• Mouse look + WASD movement
• Sprint support
• Cursor lock / unlock handling
• Designed specifically to work with drag interactions

Drawer Setup

1. Add a Collider to the drawer mesh
2. Attach the DragDrawer script
3. Interact RangeSet:
   Move Speed
   Max Z Offset
4. Assign the Interactable layer
5. Ensure the drawer opens along its local Z axis

Player Setup

1. Create a Player GameObject
2. SimpleFpsControllerAdd:
   CharacterController
3. Assign the Camera Transform
4. Make the camera a child of the Player

Interact UI Setup

1. Create a Canvas (Screen Space – Overlay)
2. A TextMeshPro Text (instruction text)Add:
   An Image (interaction icon)
3. Attach the InteractUI script to the Canvas
4. Assign the Image and TMP Text references

Controls

• Look: Mouse
• Move: WASD
• Sprint: Left Shift
• Drag Drawer: Hold Left Mouse Button
• Open / Close: Vertical Mouse Movement

Compatibility

• Unity 2022.3 LTS
• URP
• Desktop platforms

Notes

• No external dependencies
• No complex setup
• Beginner-friendly
• Easy to extend for doors, cabinets, or other drag-based objects