🧠 Project Description: Movement Detector Mod

The Movement Detector Mod is a Minecraft mod that introduces a new gameplay mechanic centered around detecting player movement within user-defined regions. The mod adds two main items: the Emerald Stick and the Movement Detector Block. Together, they create an interactive system capable of defining spatial zones, storing coordinates, and triggering lethal or custom effects when activated by redstone power.

⚙️ Core Concept

The idea behind the Movement Detector Mod is to let players define a specific area of detection in the world — similar to the WorldEdit wand selection system — and then connect that area to a detector block that can perform programmed actions (in this case, killing the player when triggered).

🧱 Main Additions

1. Emerald Stick

A custom item that works similarly to the WorldEdit wooden axe but crafted differently.

Crafting Recipe: Two emeralds placed vertically (like crafting a regular stick).
Function: Used to select a cuboid area in the world.
- Left-click on a block sets the first position.
- Right-click sets the second position.
- Once the first position is selected, a message appears in chat:
  
  “First position saved.”
- When the second position is selected, the message changes to:
  
  “Zone saved.”
- The Emerald Stick internally stores both coordinate positions.

If the player wants to clear the saved selection, they simply press the Delete key while holding the stick. When this happens, the data associated with the stick is erased, and a message appears in chat confirming:

“Selection cleared.”

This makes the Emerald Stick act as a data container item, capable of holding NBT data about the selected region.

2. Movement Detector Block

This block serves as the core of the system.

When placed in the world, it can be right-clicked to open a simple GUI containing one slot.
The player can insert the Emerald Stick into this slot.
- When the stick is inserted, the block “absorbs” it (removing it from the slot).
- It then reads and stores the positional data from the stick internally.
- Once the data is successfully loaded, the stick disappears, and the detector is now linked to the previously selected area.

From that moment on, the Movement Detector Block “knows” the region defined by the Emerald Stick.

3. Redstone Activation

When the block receives a redstone signal, it becomes active and checks for player movement or presence within the defined region.

If the player is detected inside the selected area, the block immediately kills the player (the equivalent of executing a /kill command or applying lethal damage).
This makes the block a powerful automation or trap component that can be used for:

Security systems.
Custom maps or adventure traps.
PvP arenas with restricted zones.
Redstone-based logic systems.

The system could later be expanded to include different responses, such as teleporting the player, summoning entities, or triggering explosions, but the base functionality focuses on detection and elimination.

🧩 Technical Summary

Mod Name: Movement Detector
Main Items:
- Emerald Stick (NBT-based area selector)
- Movement Detector Block (data-driven redstone device)
Creative Tab: Custom creative category exclusively for mod items.
Core Mechanic: Stores region data via item NBT, transfers it to block tile entity.
Activation Trigger: Redstone signal.
Primary Effect: Player instant death if detected inside the selected area.
Data Reset: Delete key clears Emerald Stick’s NBT data.

🧪 Future Ideas

GUI feedback showing the area coordinates or region boundaries.
Toggle options for lethal vs. non-lethal reactions.
Compatibility with other redstone or automation mods.
Visual particle effect to show the scanned zone when powered.
Option to save multiple zones with upgraded sticks.

💡 Summary

The Movement Detector Mod is a creative yet deadly automation tool for Minecraft that allows players to mark, store, and control spatial regions using a custom emerald-based wand and an intelligent detection block. Its gameplay concept merges the logic of WorldEdit selections, NBT data handling, and redstone automation, providing map makers and advanced builders with a new level of control over player presence and world interaction.