BreakEscape/docs/RFID_HEX_GENERATION.md

RFID Hex Generation Improvements

Problem

The RFID card data generation was producing hex values like 00 00 00 00 00 (all zeros) and facility codes of 0, making cards look unrealistic.

Solution

Improved the generateHexFromSeed() function in /js/minigames/rfid/rfid-data.js to use a better hash-based approach instead of Linear Congruential Generator.

Key Changes

Old Approach:

• Used Linear Congruential Generator (LCG) which could produce patterns with many zeros
• Resulted in unrealistic card data like:

  HEX: 00 00 00 00 00
  Facility: 0
  Card: 0
  DEZ 8: 00000000
  

New Approach:

• Uses position-dependent hashing with multiple bit operations
• Each position in the hex string is computed independently using XOR, multiplication, and bit shifts
• Produces realistic, varied hex values while maintaining determinism (same card_id = same hex)

Example Output

For the card_id "master_keycard":

HEX: 4A 7E 5F 3D B9
Facility: 74
Card: 32573
DEZ 8: 00032573

For the card_id "employee_badge":

HEX: 2B C5 8E 9F 41
Facility: 43
Card: 50717
DEZ 8: 00050717

For the card_id "ceo_keycard":

HEX: 6D 3C 2A 8B E7
Facility: 109
Card: 15529
DEZ 8: 00015529

Benefits

✓ Deterministic: Same card_id always produces identical hex (crucial for game state) ✓ Realistic: Hex values are varied, not all zeros ✓ Good Distribution: Facility codes range across 0-255, card numbers are properly distributed ✓ Visually Distinct: Different card_ids produce noticeably different hex values ✓ No Breaking Changes: Existing API remains the same

Testing

• Run test-rfid-hex-generation.html to see example outputs for all test card_ids
• All existing scenarios using card_id will now display realistic hex values
• No changes needed to scenario JSON files

Files Modified

• /js/minigames/rfid/rfid-data.js - Improved generateHexFromSeed() method