Fix research

core/research/README.md

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+# Research Module Documentation
+
+## Overview
+
+The `research/` subfolder implements a production-based research system where generator output earns research XP, automatically leveling up to provide production multipliers. Research tracks are tied to specific generators and can be enhanced with purchasable buffs that increase XP gain.
+
+## Files
+
+| File | Purpose |
+|------|---------|
+| `research_xp_tracker.gd` | Accumulates XP from production and handles auto-leveling (Node) |
+| `research_catalogue.gd` | Resource holding all research configurations |
+| `research_panel.gd` | UI panel showing all research tracks |
+| `research_row.gd` | UI row component for individual research display |
+
+## Architecture
+
+```
+LevelGameState (Node2D)
+├── ResearchXPTracker (child node)
+│   ├── Receives production_tick signals
+│   ├── Applies buff multipliers
+│   ├── Awards XP to research tracks
+│   └── Auto-levels when thresholds reached
+├── research_xp: Dictionary
+├── research_levels: Dictionary
+└── research_catalogue: ResearchCatalogue
+	└── ResearchPanel (UI, always visible)
+		├── ResearchRow (for each research track)
+		│   ├── Name & icon
+		│   ├── Level display
+		│   ├── Progress bar (percentage)
+		│   ├── Multiplier indicator
+		│   └── Active buff display
+```
+
+## Data Flow
+
+```
+Generator Production (currency_per_cycle)
+	│
+	▼
+ResearchXPTracker
+	1. base_xp = currency_produced * xp_per_currency_produced
+	2. actual_xp = base_xp * buff_multiplier
+	3. research_xp += actual_xp
+	4. Check level threshold → auto-level
+	5. Emit research_level_up signal
+	│
+	▼
+ResearchState {xp: 150.5, level: 3}
+	│
+	▼
+CurrencyGenerator.get_research_multiplier() → 1.3 (30% bonus)
+	│
+	▼
+Production *= 1.3
+```
+
+## ResearchData
+
+Resource class defining research configuration for a generator (defined in `core/generator/research_data.gd`).
+
+### Key Properties
+
+```gdscript
+@export var id: StringName                              # Unique research identifier
+@export var generator_id: StringName                    # Which generator this affects
+@export var name: String                                # Display name
+@export_multiline var description: String = ""          # Description text
+@export var icon: Texture2D                             # Icon for UI
+
+# XP Configuration
+@export var xp_per_currency_produced: float = 0.01      # XP per 1 currency unit
+@export var base_xp_required: float = 100.0             # XP needed for level 1
+@export var xp_growth_multiplier: float = 1.5           # XP requirement growth per level
+
+# Multiplier Configuration
+@export var base_multiplier: float = 1.0                # Production multiplier at level 0
+@export var multiplier_per_level: float = 0.1           # +10% production per level
+
+# Associated Buff (single buff per research track)
+@export var associated_buff_id: StringName              # Buff that increases XP gain
+```
+
+### Key Methods
+
+```gdscript
+func get_xp_required_for_level(level: int) -> float:
+	"""XP needed to reach this level from previous"""
+	return base_xp_required * pow(xp_growth_multiplier, float(maxi(level - 1, 0)))
+
+func get_xp_required_for_level_big(level: int) -> BigNumber:
+	"""XP needed to reach this level from previous (BigNumber)"""
+	return BigNumber.from_float(base_xp_required * pow(xp_growth_multiplier, float(maxi(level - 1, 0))))
+
+func get_total_xp_for_level(level: int) -> BigNumber:
+	"""Total cumulative XP needed to reach this level from level 0 (BigNumber)"""
+	if level <= 0: return BigNumber.new(0.0, 0)
+	var total: BigNumber = BigNumber.new(0.0, 0)
+	for l in range(1, level + 1):
+		total = total.add(get_xp_required_for_level_big(l))
+	return total
+
+func get_level_for_xp(xp: BigNumber) -> int:
+	"""Calculate level from total accumulated BigNumber XP (loop-based)"""
+	if xp.mantissa == 0.0: return 0
+	var level: int = 0
+	while true:
+		var next_xp: BigNumber = get_total_xp_for_level(level + 1)
+		if xp.compare_to(next_xp) < 0: break
+		level += 1
+	return level
+
+func get_multiplier_for_level(level: int) -> float:
+	"""Production multiplier at given level"""
+	return base_multiplier + (multiplier_per_level * float(maxi(level, 0)))
+
+func get_xp_progress(xp: float) -> float:
+	"""Returns 0.0-1.0 progress to next level"""
+```
+
+## ResearchCatalogue
+
+Resource class holding all research configurations.
+
+### Structure
+
+```gdscript
+class_name ResearchCatalogue
+extends Resource
+
+@export var research_entries: Array[ResearchData] = []
+
+func get_research_by_id(research_id: StringName) -> ResearchData
+func get_research_by_generator_id(generator_id: StringName) -> ResearchData
+func get_all_research() -> Array[ResearchData]
+```
+
+### Usage
+
+Referenced directly by `LevelGameState` via `@export var research_catalogue: ResearchCatalogue`.
+
+## ResearchXPTracker
+
+Child node of `LevelGameState` that accumulates XP from production and applies buff multipliers.
+
+### Signals
+
+```gdscript
+signal research_xp_changed(research_id: StringName, new_xp: float)
+signal research_level_up(research_id: StringName, old_level: int, new_level: int)
+```
+
+### Key Methods
+
+```gdscript
+func add_xp_with_buffs(research_id: StringName, base_xp: BigNumber) -> BigNumber:
+	"""Apply buff multipliers and award XP. Returns actual XP after buffs (BigNumber)."""
+	var buff_multiplier: float = game_state.get_research_xp_multiplier(research_id)
+	var multiplier_bn: BigNumber = BigNumber.from_float(buff_multiplier)
+	var actual_xp: BigNumber = base_xp.multiply(multiplier_bn)
+	game_state.add_research_xp(research_id, actual_xp)
+	return actual_xp
+
+func _on_generator_produced(generator_id: StringName, amount: BigNumber) -> void:
+	var research: ResearchData = _get_research_for_generator(generator_id)
+	var amount_float: float = amount.mantissa * pow(10.0, float(amount.exponent))
+	var base_xp: BigNumber = BigNumber.from_float(research.xp_per_currency_produced * amount_float)
+	add_xp_with_buffs(research.id, base_xp)
+```
+
+### Connection
+
+Connected to `LevelGameState` via `generator_produced` signal.
+
+## LevelGameState Extensions
+
+### State Variables
+```gdscript
+var research_xp: Dictionary = {}        # {research_id: BigNumber}
+var research_levels: Dictionary = {}    # {research_id: level_int}
+var research_tracker: ResearchXPTracker
+```
+
+### Signals
+```gdscript
+signal research_xp_changed(research_id: StringName, new_xp: BigNumber)
+signal research_level_up(research_id: StringName, old_level: int, new_level: int)
+```
+
+### Key Methods
+```gdscript
+func register_research(research_id: StringName) -> void:
+	"""Initialize research state from catalogue (BigNumber XP)"""
+	if not research_xp.has(research_id):
+		research_xp[research_id] = BigNumber.new(0.0, 0)
+
+func get_research_xp(research_id: StringName) -> BigNumber
+
+func get_research_level(research_id: StringName) -> int
+
+func get_research_multiplier(research_id: StringName) -> float:
+	"""Returns production multiplier from research level"""
+	var level: int = get_research_level(research_id)
+	return research.get_multiplier_for_level(level)
+
+func add_research_xp(research_id: StringName, xp: BigNumber) -> void:
+	"""Add XP (BigNumber) and auto-level if threshold reached"""
+	var current_xp: BigNumber = get_research_xp(research_id)
+	research_xp[research_id] = current_xp.add(xp)
+	new_level = research.get_level_for_xp(research_xp[research_id])
+	if new_level > old_level:
+		research_levels[research_id] = new_level
+		research_level_up.emit(research_id, old_level, new_level)
+
+func get_research_xp_multiplier(research_id: StringName) -> float:
+	"""Returns multiplicative buff for research XP gain"""
+	var multiplier: float = 1.0
+	var buff: GeneratorBuffData = get_buff(research.associated_buff_id)
+	if is_buff_active(buff.id):
+		multiplier *= buff.get_effect_multiplier(get_buff_level(buff.id))
+	return multiplier
+```
+
+### Save/Load Integration
+```gdscript
+const RESEARCH_XP_KEY = "research_xp"
+const RESEARCH_LEVELS_KEY = "research_levels"
+const CURRENT_SAVE_FORMAT_VERSION = 5  # Bumped from 4 to support BigNumber
+
+# In save_game():
+var save_data = {
+	# ... existing fields ...
+	RESEARCH_XP_KEY: _serialize_research_xp(),  # Serialize BigNumber as {m, e}
+	RESEARCH_LEVELS_KEY: research_levels.duplicate(),
+}
+
+func _serialize_research_xp() -> Dictionary:
+	var result: Dictionary = {}
+	for research_id in research_xp.keys():
+		var xp: BigNumber = research_xp[research_id]
+		result[research_id] = xp.serialize()
+	return result
+
+# In load_game():
+research_xp = _deserialize_research_xp(parsed_data.get(RESEARCH_XP_KEY, {}))
+research_levels = parsed_data.get(RESEARCH_LEVELS_KEY, {})
+
+func _deserialize_research_xp(raw: Variant) -> Dictionary:
+	var result: Dictionary = {}
+	if raw is Dictionary:
+		for research_id in raw.keys():
+			var serialized: Variant = raw[research_id]
+			if serialized is Dictionary:
+				result[research_id] = BigNumber.deserialize(serialized)
+	return result
+
+# In reset_for_prestige():
+research_xp.clear()
+research_levels.clear()
+```
+
+## CurrencyGenerator Extensions
+
+### Production Tick Integration
+```gdscript
+func _grant_cycle_income(cycle_count: int) -> void:
+	var produced: BigNumber = ...
+	_add_currency(produced)
+	production_tick.emit(produced, cycle_count, owned)
+	
+	# Award research XP (BigNumber)
+	if data.research_data != null:
+		var amount_float: float = produced.mantissa * pow(10.0, float(produced.exponent))
+		var xp: BigNumber = BigNumber.from_float(data.research_data.xp_per_currency_produced * amount_float)
+		research_tracker.add_xp_with_buffs(data.research_data.id, xp)
+```
+
+### Research Multiplier
+
+```gdscript
+func get_research_multiplier() -> float:
+	if data.research_data == null:
+		return 1.0
+	return game_state.get_research_multiplier(data.research_data.id)
+
+func get_effective_auto_run_multiplier() -> float:
+	return run_multiplier * get_research_multiplier() * get_automatic_production_multiplier() * _get_prestige_multiplier()
+```
+
+## GeneratorBuffData Extensions
+
+### New Buff Kind
+
+```gdscript
+enum BuffKind {
+	AUTO_PRODUCTION_MULTIPLIER,
+	MANUAL_CLICK_MULTIPLIER,
+	RESOURCE_PURCHASE,
+	RESEARCH_XP_MULTIPLIER  # Increases research XP gain
+}
+```
+
+### New Properties (for RESEARCH_XP_MULTIPLIER buffs)
+
+```gdscript
+@export var research_target_id: StringName  # Which research track this buff affects
+@export var xp_multiplier_per_level: float = 0.1  # +10% XP per level
+```
+
+## ResearchPanel
+
+UI component showing all research tracks (always visible, like GeneratorPanel).
+
+### Layout
+
+```
+ResearchPanel (ScrollContainer)
+└── VBoxContainer
+	├── TitleLabel ("Research")
+	└── ResearchRows (VBoxContainer)
+		└── ResearchRow (for each research track)
+```
+
+### Key Methods
+
+```gdscript
+func _build_research_rows() -> void:
+	for research in research_catalogue.get_all_research():
+		var row = RESEARCH_ROW_SCENE.instantiate()
+		row.setup(research)
+		_research_rows[research.id] = row
+
+func _refresh_row(row) -> void:
+	var research_id: StringName = row.get_research_id()
+	var xp: BigNumber = game_state.get_research_xp(research_id)
+	var level: int = game_state.get_research_level(research_id)
+	var progress: float = research.get_xp_progress(xp)
+	var multiplier: float = research.get_multiplier_for_level(level)
+	var xp_current: BigNumber = xp.subtract(research.get_total_xp_for_level(level))
+	var xp_needed: BigNumber = research.get_xp_required_for_level_big(level + 1)
+	row.update_display(level, progress, multiplier, xp_current, xp_needed)
+```
+
+### Signals Connected
+
+- `research_xp_changed` - Refresh progress bars
+- `research_level_up` - Refresh level and multiplier displays
+
+## ResearchRow
+
+UI row component for individual research display.
+
+### UI Layout
+
+```
+ResearchRow (HBoxContainer)
+├── Icon (TextureRect)
+├── VBoxContainer
+│   ├── NameLabel ("Gold Mine Research")
+│   └── LevelLabel ("Level 3")
+├── ProgressBar (with percentage label "75%")
+├── MultiplierLabel ("+30%")
+└── BuffLabel ("Mining Expert: +20% XP")
+```
+
+### Key Methods
+
+```gdscript
+func setup(research: ResearchData) -> void:
+	_name_label.text = research.name
+	_icon.texture = research.icon
+
+func update_display(level: int, progress: float, multiplier: float, xp_current: BigNumber, xp_needed: BigNumber) -> void:
+	_level_label.text = "Level %d" % level
+	_progress_bar.value = progress * 100
+	_progress_label.text = "%d%%" % int(progress * 100)
+	_multiplier_label.text = "+%d%%" % int((multiplier - 1.0) * 100)
+	
+	# Update buff label if buff is active
+	if _research.associated_buff_id != &"":
+		var buff: GeneratorBuffData = game_state.get_buff(_research.associated_buff_id)
+		if is_buff_active(buff.id):
+			_buff_label.text = "%s: +%d%% XP" % [buff.text, int(effect * 100)]
+```
+
+## Formulas
+
+### XP Calculation
+
+```
+base_xp = currency_produced * xp_per_currency_produced
+actual_xp = base_xp * buff_multiplier
+```
+
+### Level Progression
+
+```
+xp_required_for_level(n) = base_xp_required * (xp_growth_multiplier ^ (n - 1))
+total_xp_for_level(n) = sum(xp_required_for_level(i) for i in 1..n)
+level = get_level_for_xp(total_xp)
+```
+
+### Production Multiplier
+
+```
+multiplier = base_multiplier + (multiplier_per_level * level)
+effective_production = base_production * multiplier
+```
+
+### Buff XP Multiplier
+
+```
+xp_multiplier = 1.0
+for each active buff targeting this research:
+	xp_multiplier *= buff.get_effect_multiplier(level)
+actual_xp = base_xp * xp_multiplier
+```
+
+## Design Decisions
+
+| Decision | Value |
+|----------|-------|
+| ResearchCatalogue reference | Direct `@export var research_catalogue: ResearchCatalogue` in LevelGameState |
+| ResearchXPTracker location | Child of `LevelGameState` (receives signals via connection) |
+| Progress bar display | Percentage format (e.g., "75%") |
+| Buff display | Shows buff name and effect (e.g., "Mining Expert: +20% XP") |
+| Research unlock | Starts unlocked |
+| XP formula | Production-based: `XP = currency_produced * xp_per_currency_produced` |
+| Level-up | Auto-level when XP threshold reached |
+| Buffs | Single buff per research track, multiplicative XP bonus |
+| Prestige | Research levels and XP reset to 0 |
+| ResearchPanel visibility | Always visible (like GeneratorPanel) |
+
+## System Behavior
+
+1. **Generator produces currency** → `production_tick` signal emitted
+2. **ResearchXPTracker receives signal** → calculates base XP from production amount
+3. **Buff multipliers applied** → checks for active RESEARCH_XP_MULTIPLIER buffs
+4. **XP awarded** → stored in `research_xp` dictionary
+5. **Level check** → if XP exceeds threshold, auto-level and emit `research_level_up`
+6. **Multiplier applied** → `get_research_multiplier()` returns updated production bonus
+7. **UI refresh** → `ResearchPanel` updates progress bars and level displays
+
+## Prestige Integration
+
+On prestige reset:
+1. `research_xp.clear()` - All XP lost
+2. `research_levels.clear()` - All levels reset to 0
+3. Buff purchases persist (separate state)
+4. Research tracks remain unlocked
+
+## See Also
+
+- `core/level_game_state.gd` - Research state storage and management
+- `core/generator/currency_generator_data.gd` - Links to ResearchData
+- `core/generator/generator_buff_data.gd` - RESEARCH_XP_MULTIPLIER buff type
+- `core/research/research_catalogue.gd` - Research configuration resource

core/research/TODO.md

@@ -0,0 +1,645 @@
+# Research Feature Implementation Plan
+
+## Overview
+
+A production-based research system where:
+- **Generator production → Research XP → Auto-level → Production multiplier**
+- **Research buffs** (purchased with currency) increase XP gain multiplicatively
+- **One research track per generator** with a single associated buff
+- **Progress bar shows percentage** to next level
+- **Buff display shows name and effect**
+- **Research tracks start unlocked**
+- **Resets on prestige** (levels and XP lost)
+
+---
+
+## System Architecture
+
+```
+┌─────────────────────────────────────────────────────────────────┐
+│                         LevelGameState                           │
+│  ┌─────────────────────────────────────────────────────────┐   │
+│  │              ResearchXPTracker (child node)              │   │
+│  │  - Receives production_tick signals                      │   │
+│  │  - Applies buff multipliers                              │   │
+│  │  - Awards XP to research tracks                          │   │
+│  │  - Auto-levels when thresholds reached                   │   │
+│  └─────────────────────────────────────────────────────────┘   │
+│  - research_xp: Dictionary                                       │
+│  - research_levels: Dictionary                                   │
+│  - research_catalogue: ResearchCatalogue                         │
+└─────────────────────────────────────────────────────────────────┘
+							  │
+		  ┌───────────────────┼───────────────────┐
+		  ▼                   ▼                   ▼
+┌─────────────────┐  ┌─────────────────┐  ┌─────────────────┐
+│ CurrencyGen     │  │ ResearchData    │  │ ResearchPanel   │
+│ (Gold Mine)     │──│ (Resource)      │──│ (Always visible)│
+│ - produces gold │  │ - XP config     │  │ - Shows all     │
+│ - emits signal  │  │ - Multiplier    │  │   research      │
+└─────────────────┘  └─────────────────┘  │ - Progress bars │
+										  └─────────────────┘
+```
+
+---
+
+## Data Flow
+
+```
+Generator Production (currency_per_cycle)
+		 │
+		 ▼
+┌──────────────────────┐
+│ ResearchXPTracker    │
+│ 1. base_xp = currency_produced * xp_per_currency_produced
+│ 2. actual_xp = base_xp * buff_multiplier
+│ 3. research_xp += actual_xp
+│ 4. Check level threshold → auto-level
+│ 5. Emit research_level_up signal
+└──────────────────────┘
+		 │
+		 ▼
+┌──────────────────────┐
+│ ResearchState        │
+│ {xp: 150.5, level: 3}│
+└──────────────────────┘
+		 │
+		 ▼
+┌──────────────────────┐
+│ CurrencyGen          │
+│ get_research_multiplier() → 1.3 (30% bonus)
+└──────────────────────┘
+		 │
+		 ▼
+┌──────────────────────┐
+│ Production *= 1.3    │
+└──────────────────────┘
+```
+
+---
+
+## Component Specifications
+
+### 1. ResearchData (core/generator/research_data.gd)
+
+**Purpose:** Resource defining research configuration for a generator
+
+**Location:** `res://core/generator/research_data.gd`
+
+**Key Properties:**
+```gdscript
+@export var id: StringName                              # Unique research identifier
+@export var generator_id: StringName                    # Which generator this research affects
+@export var name: String                                # Display name
+@export_multiline var description: String = ""          # Description text
+@export var icon: Texture2D                             # Icon for UI
+
+# XP Configuration
+@export var xp_per_currency_produced: float = 0.01      # XP per 1 currency unit produced
+@export var base_xp_required: float = 100.0             # XP needed for level 1
+@export var xp_growth_multiplier: float = 1.5           # XP requirement growth per level
+
+# Multiplier Configuration
+@export var base_multiplier: float = 1.0                # Production multiplier at level 0
+@export var multiplier_per_level: float = 0.1           # +10% production per level
+
+# Associated Buff (single buff per research track)
+@export var associated_buff_id: StringName              # Buff that increases XP gain
+```
+
+**Key Methods:**
+```gdscript
+func get_xp_required_for_level(level: int) -> float:
+	"""XP needed to reach this level from previous"""
+	return base_xp_required * pow(xp_growth_multiplier, float(maxi(level - 1, 0)))
+
+func get_total_xp_for_level(level: int) -> float:
+	"""Total cumulative XP needed to reach this level from level 0"""
+	if level <= 0:
+		return 0.0
+	var total: float = 0.0
+	for l in range(1, level + 1):
+		total += get_xp_required_for_level(l)
+	return total
+
+func get_level_for_xp(xp: float) -> int:
+	"""Calculate level from total accumulated XP"""
+	var level: int = 0
+	var cumulative_xp: float = 0.0
+	while true:
+		var next_xp: float = cumulative_xp + get_xp_required_for_level(level + 1)
+		if xp < next_xp:
+			break
+		level += 1
+		cumulative_xp = next_xp
+	return level
+
+func get_multiplier_for_level(level: int) -> float:
+	"""Production multiplier at given level"""
+	return base_multiplier + (multiplier_per_level * float(maxi(level, 0)))
+
+func get_xp_progress(xp: float) -> float:
+	"""Returns 0.0-1.0 progress to next level"""
+	if xp <= 0.0:
+		return 0.0
+	var current_level: int = get_level_for_xp(xp)
+	if current_level < 0:
+		return 0.0
+	
+	var xp_at_current_level: float = get_total_xp_for_level(current_level)
+	var xp_needed_for_next: float = get_xp_required_for_level(current_level + 1)
+	var xp_in_current_level: float = xp - xp_at_current_level
+	
+	return clampf(xp_in_current_level / xp_needed_for_next, 0.0, 1.0)
+```
+
+---
+
+### 2. ResearchCatalogue (core/research/research_catalogue.gd)
+
+**Purpose:** Resource holding all research configurations
+
+**Location:** `res://core/research/research_catalogue.gd`
+
+**Structure:**
+```gdscript
+class_name ResearchCatalogue
+extends Resource
+
+@export var research_entries: Array[ResearchData] = []
+
+func get_research_by_id(research_id: StringName) -> ResearchData:
+	for entry in research_entries:
+		if entry.id == research_id:
+			return entry
+	return null
+
+func get_research_by_generator_id(generator_id: StringName) -> ResearchData:
+	for entry in research_entries:
+		if entry.generator_id == generator_id:
+			return entry
+	return null
+
+func get_all_research() -> Array[ResearchData]:
+	return research_entries.duplicate()
+```
+
+**Usage:** Referenced directly by LevelGameState via `@export var research_catalogue: ResearchCatalogue`
+
+---
+
+### 3. ResearchXPTracker (core/research/research_xp_tracker.gd)
+
+**Purpose:** Child of LevelGameState; accumulates XP from production and applies buff multipliers
+
+**Location:** `res://core/research/research_xp_tracker.gd`
+
+**Signals:**
+```gdscript
+signal research_xp_changed(research_id: StringName, new_xp: float)
+signal research_level_up(research_id: StringName, old_level: int, new_level: int)
+```
+
+**Key Methods:**
+```gdscript
+func add_xp_with_buffs(research_id: StringName, base_xp: float) -> float:
+	"""Apply buff multipliers and award XP. Returns actual XP after buffs."""
+	if game_state == null:
+		return 0.0
+	
+	var actual_xp: float = base_xp
+	
+	# Apply research-specific buff multiplier
+	var buff_multiplier: float = game_state.get_research_xp_multiplier(research_id)
+	actual_xp *= buff_multiplier
+	
+	# Award XP (handles auto-leveling internally)
+	game_state.add_research_xp(research_id, actual_xp)
+	
+	return actual_xp
+
+func _on_generator_produced(generator_id: StringName, amount: BigNumber) -> void:
+	var research: ResearchData = _get_research_for_generator(generator_id)
+	if research == null:
+		return
+	
+	var amount_float: float = amount.to_float()
+	if amount_float <= 0.0:
+		return
+	
+	var base_xp: float = research.xp_per_currency_produced * amount_float
+	if base_xp <= 0.0:
+		return
+	
+	add_xp_with_buffs(research.id, base_xp)
+```
+
+**Connection:** Connected to `LevelGameState` via `generator_produced` signal
+
+---
+
+### 4. LevelGameState Extensions (core/level_game_state.gd)
+
+**New State Variables:**
+```gdscript
+var research_xp: Dictionary = {}        # {research_id: xp_float}
+var research_levels: Dictionary = {}    # {research_id: level_int}
+var research_tracker: ResearchXPTracker
+```
+
+**New Signals:**
+```gdscript
+signal research_xp_changed(research_id: StringName, new_xp: float)
+signal research_level_up(research_id: StringName, old_level: int, new_level: int)
+```
+
+**New Properties:**
+```gdscript
+@export var research_catalogue: ResearchCatalogue
+```
+
+**New Methods:**
+```gdscript
+func register_research(research_id: StringName) -> void:
+	if not research_xp.has(research_id):
+		research_xp[research_id] = 0.0
+	if not research_levels.has(research_id):
+		research_levels[research_id] = 0
+
+func get_research_xp(research_id: StringName) -> float:
+	return research_xp.get(research_id, 0.0)
+
+func get_research_level(research_id: StringName) -> int:
+	return research_levels.get(research_id, 0)
+
+func get_research_multiplier(research_id: StringName) -> float:
+	var level: int = get_research_level(research_id)
+	var research: ResearchData = _get_research_data(research_id)
+	if research == null:
+		return 1.0
+	return research.get_multiplier_for_level(level)
+
+func add_research_xp(research_id: StringName, xp: float) -> void:
+	var old_level: int = get_research_level(research_id)
+	research_xp[research_id] = research_xp.get(research_id, 0.0) + xp
+	
+	var new_level: int = _get_research_data(research_id).get_level_for_xp(research_xp[research_id])
+	
+	if new_level > old_level:
+		research_levels[research_id] = new_level
+		research_level_up.emit(research_id, old_level, new_level)
+	
+	research_xp_changed.emit(research_id, research_xp[research_id])
+
+func get_research_xp_multiplier(research_id: StringName) -> float:
+	"""Returns multiplicative buff for research XP gain"""
+	var multiplier: float = 1.0
+	var research: ResearchData = _get_research_data(research_id)
+	if research == null:
+		return 1.0
+	
+	# Find associated buff and apply its multiplier
+	if not research.associated_buff_id.is_empty():
+		var buff: GeneratorBuffData = get_buff(research.associated_buff_id)
+		if buff != null and is_buff_active(buff.id):
+			var level: int = get_buff_level(buff.id)
+			multiplier *= buff.get_effect_multiplier(level)
+	
+	return multiplier
+
+func _get_research_data(research_id: StringName) -> ResearchData:
+	if research_catalogue == null:
+		return null
+	return research_catalogue.get_research_by_id(research_id)
+```
+
+**Save/Load Integration:**
+```gdscript
+const RESEARCH_XP_KEY = "research_xp"
+const RESEARCH_LEVELS_KEY = "research_levels"
+
+# In save_game():
+var save_data = {
+	# ... existing fields ...
+	RESEARCH_XP_KEY: research_xp.duplicate(),
+	RESEARCH_LEVELS_KEY: research_levels.duplicate(),
+}
+
+# In load_game():
+if parsed_data.has(RESEARCH_XP_KEY):
+	research_xp = parsed_data.get(RESEARCH_XP_KEY, {})
+if parsed_data.has(RESEARCH_LEVELS_KEY):
+	research_levels = parsed_data.get(RESEARCH_LEVELS_KEY, {})
+
+# In reset_for_prestige():
+research_xp.clear()
+research_levels.clear()
+```
+
+**Initialization in _ready():**
+```gdscript
+# After initializing other state, create research tracker
+research_tracker = ResearchXPTracker.new()
+add_child(research_tracker)
+research_tracker.game_state = self
+
+# Initialize research state from catalogue
+if research_catalogue:
+	for research in research_catalogue.get_all_research():
+		register_research(research.id)
+```
+
+---
+
+### 5. CurrencyGeneratorData Extensions (core/generator/currency_generator_data.gd)
+
+**New Property:**
+```gdscript
+@export var research_data: ResearchData  # Link to research configuration
+```
+
+---
+
+### 6. CurrencyGenerator Extensions (core/generator/currency_generator.gd)
+
+**In `_grant_cycle_income()`:**
+```gdscript
+func _grant_cycle_income(cycle_count: int) -> void:
+	if data == null or cycle_count <= 0:
+		return
+
+	var effective_run_multiplier: float = get_effective_auto_run_multiplier()
+	var per_cycle: float = data.production_per_cycle(owned, effective_run_multiplier, purchased_count)
+	if per_cycle <= 0.0:
+		return
+
+	var produced: BigNumber = BigNumber.from_float(per_cycle).multiply(BigNumber.from_float(float(cycle_count)))
+	_add_currency(produced)
+	production_tick.emit(produced, cycle_count, owned)
+	
+	# NEW: Award research XP
+	if data.research_data != null:
+		var xp: float = data.research_data.xp_per_currency_produced * produced.to_float()
+		research_tracker.add_xp_with_buffs(data.research_data.id, xp)
+```
+
+**New Method:**
+```gdscript
+func get_research_multiplier() -> float:
+	if data == null or data.research_data == null:
+		return 1.0
+	if game_state == null:
+		return 1.0
+	return game_state.get_research_multiplier(data.research_data.id)
+```
+
+**Modify `get_effective_auto_run_multiplier()`:**
+```gdscript
+func get_effective_auto_run_multiplier() -> float:
+	return run_multiplier * get_research_multiplier() * get_automatic_production_multiplier() * _get_prestige_multiplier()
+```
+
+**In `_ready()`:**
+```gdscript
+# Get reference to research tracker
+if game_state:
+	research_tracker = game_state.research_tracker
+```
+
+---
+
+### 7. GeneratorBuffData Extensions (core/generator/generator_buff_data.gd)
+
+**New Enum Value:**
+```gdscript
+enum BuffKind {
+	AUTO_PRODUCTION_MULTIPLIER,
+	MANUAL_CLICK_MULTIPLIER,
+	RESOURCE_PURCHASE,
+	RESEARCH_XP_MULTIPLIER  # NEW: Increases research XP gain
+}
+```
+
+**New Properties (for RESEARCH_XP_MULTIPLIER buffs):**
+```gdscript
+@export var research_target_id: StringName  # Which research track this buff affects
+@export var xp_multiplier_per_level: float = 0.1  # +10% XP per level (uses get_effect_multiplier)
+```
+
+**Note:** Buff names are configured in the `text` field of each `GeneratorBuffData` instance
+
+---
+
+### 8. ResearchRow (core/research/research_row.tscn + .gd)
+
+**Location:**
+- Script: `res://core/research/research_row.gd`
+- Scene: `res://core/research/research_row.tscn`
+
+**UI Layout:**
+```
+ResearchRow (HBoxContainer)
+├── Icon (TextureRect)
+├── VBoxContainer
+│   ├── NameLabel ("Gold Mine Research")
+│   └── LevelLabel ("Level 3")
+├── ProgressBar (with percentage label "75%")
+├── MultiplierLabel ("+30%")
+└── BuffLabel ("Mining Expert: +20% XP")
+```
+
+**Script Methods:**
+```gdscript
+func setup(research: ResearchData) -> void:
+	"""Initialize row with research data"""
+	_research = research
+	_name_label.text = research.name
+	_icon.texture = research.icon
+
+func update_display(level: int, progress: float, multiplier: float, xp_current: float, xp_needed: float) -> void:
+	"""Update UI elements"""
+	_level_label.text = "Level %d" % level
+	_progress_bar.value = progress * 100
+	_progress_label.text = "%d%%" % int(progress * 100)
+	_multiplier_label.text = "+%d%%" % int((multiplier - 1.0) * 100)
+	
+	# Update buff label if buff is active
+	if _research.associated_buff_id != &"":
+		var buff: GeneratorBuffData = game_state.get_buff(_research.associated_buff_id)
+		if buff != null and game_state.is_buff_active(buff.id):
+			var level: int = game_state.get_buff_level(buff.id)
+			var effect: float = buff.get_effect_multiplier(level) - 1.0
+			_buff_label.text = "%s: +%d%% XP" % [buff.text, int(effect * 100)]
+```
+
+---
+
+### 9. ResearchPanel (core/research/research_panel.tscn + .gd)
+
+**Location:**
+- Script: `res://core/research/research_panel.gd`
+- Scene: `res://core/research/research_panel.tscn`
+
+**Layout:**
+```
+ResearchPanel (ScrollContainer)
+├── VBoxContainer
+│   ├── TitleLabel ("Research")
+│   └── ResearchRows (VBoxContainer)
+│       └── ResearchRow (for each research track)
+```
+
+**Script Methods:**
+```gdscript
+func _ready() -> void:
+	_game_state = find_parent("LevelGameState")
+	if _game_state == null:
+		return
+	
+	_game_state.research_xp_changed.connect(_on_research_xp_changed)
+	_game_state.research_level_up.connect(_on_research_level_up)
+	
+	_build_research_rows()
+	_refresh_all()
+
+func _build_research_rows() -> void:
+	for child in _research_rows_container.get_children():
+		child.queue_free()
+	_research_rows.clear()
+	
+	if _game_state.research_catalogue:
+		for research in _game_state.research_catalogue.get_all_research():
+			var row = RESEARCH_ROW_SCENE.instantiate()
+			_research_rows_container.add_child(row)
+			row.setup(research)
+			_research_rows[research.id] = row
+
+func _refresh_all() -> void:
+	for row in _research_rows.values():
+		_refresh_row(row)
+
+func _refresh_row(row) -> void:
+	var research_id: StringName = row.get_research_id()
+	var xp: float = _game_state.get_research_xp(research_id)
+	var level: int = _game_state.get_research_level(research_id)
+	var research: ResearchData = _game_state.research_catalogue.get_research_by_id(research_id)
+	
+	if research != null:
+		var progress: float = research.get_xp_progress(xp)
+		var multiplier: float = research.get_multiplier_for_level(level)
+		var xp_current: float = xp - research.get_total_xp_for_level(level)
+		var xp_needed: float = research.get_xp_required_for_level(level + 1)
+		
+		row.update_display(level, progress, multiplier, xp_current, xp_needed)
+
+func _on_research_xp_changed(research_id: StringName, _new_xp: float) -> void:
+	if _research_rows.has(research_id):
+		_refresh_row(_research_rows[research_id])
+
+func _on_research_level_up(research_id: StringName, _old_level: int, _new_level: int) -> void:
+	if _research_rows.has(research_id):
+		_refresh_row(_research_rows[research_id])
+```
+
+---
+
+## Implementation Sequence
+
+| Step | Task | Files | Priority | Status |
+|------|------|-------|----------|--------|
+| 1 | Create `ResearchData` resource class | `core/generator/research_data.gd` | High | ⬜ |
+| 2 | Create `ResearchCatalogue` resource class | `core/research/research_catalogue.gd` | High | ⬜ |
+| 3 | Create `ResearchXPTracker` node class | `core/research/research_xp_tracker.gd` | High | ⬜ |
+| 4 | Add research state to `LevelGameState` | `core/level_game_state.gd` | High | ⬜ |
+| 5 | Add `RESEARCH_XP_MULTIPLIER` buff kind | `core/generator/generator_buff_data.gd` | High | ⬜ |
+| 6 | Add `research_data` export to `CurrencyGeneratorData` | `core/generator/currency_generator_data.gd` | High | ⬜ |
+| 7 | Connect production to research XP in `CurrencyGenerator` | `core/generator/currency_generator.gd` | High | ⬜ |
+| 8 | Create `ResearchRow` scene & script | `core/research/research_row.tscn`, `.gd` | Medium | ⬜ |
+| 9 | Create `ResearchPanel` scene & script | `core/research/research_panel.tscn`, `.gd` | Medium | ⬜ |
+| 10 | Add save/load support for research state | `core/level_game_state.gd` | Medium | ⬜ |
+| 11 | Add prestige reset for research | `core/level_game_state.gd` | Medium | ⬜ |
+| 12 | Create sample `ResearchData` resource | `doc/gyms/tiny_sword/resources/` | Low | ⬜ |
+| 13 | Test integration | Manual testing | Low | ⬜ |
+
+---
+
+## Design Decisions (Confirmed)
+
+| Decision | Value |
+|----------|-------|
+| ResearchCatalogue reference | Direct `@export var research_catalogue: ResearchCatalogue` in LevelGameState |
+| ResearchCatalogue location | `core/research/research_catalogue.gd` (resource, referenced directly) |
+| ResearchXPTracker location | Child of `LevelGameState` (receives signals via connection) |
+| Progress bar display | Percentage format (e.g., "75%") |
+| Buff display | Shows buff name and effect (e.g., "Mining Expert: +20% XP") |
+| Research unlock | Starts unlocked |
+| XP formula | Production-based: `XP = currency_produced * xp_per_currency_produced` |
+| Level-up | Auto-level when XP threshold reached |
+| Buffs | Single buff per research track, multiplicative XP bonus |
+| Prestige | Research levels and XP reset to 0 |
+| ResearchData location | `res://doc/gyms/tiny_sword/resources/` |
+| ResearchPanel visibility | Always visible (like GeneratorPanel) |
+
+---
+
+## Formulas
+
+### XP Calculation
+```
+base_xp = currency_produced * xp_per_currency_produced
+actual_xp = base_xp * buff_multiplier
+```
+
+### Level Progression
+```
+xp_required_for_level(n) = base_xp_required * (xp_growth_multiplier ^ (n - 1))
+total_xp_for_level(n) = sum(xp_required_for_level(i) for i in 1..n)
+level = get_level_for_xp(total_xp)
+```
+
+### Production Multiplier
+```
+multiplier = base_multiplier + (multiplier_per_level * level)
+effective_production = base_production * multiplier
+```
+
+### Buff XP Multiplier
+```
+xp_multiplier = 1.0
+for each active buff targeting this research:
+	xp_multiplier *= buff.get_effect_multiplier(level)
+actual_xp = base_xp * xp_multiplier
+```
+
+---
+
+## Notes
+
+- **ResearchData instances** should be created as `.tres` resources in `doc/gyms/tiny_sword/resources/`
+- **Associated buffs** should be created as `GeneratorBuffData` with `BuffKind.RESEARCH_XP_MULTIPLIER`
+- **Buff names** are configured in the `text` field of each `GeneratorBuffData`
+- **ResearchPanel** should be added as a child node in the main game scene (always visible)
+- **Save format version** should be incremented to 4 when adding research support
+
+---
+
+## Testing Checklist
+
+- [ ] Generator produces currency → research XP increases
+- [ ] Buff multipliers correctly applied to XP gain
+- [ ] Auto-level triggers at correct XP thresholds
+- [ ] Production multiplier updates after level-up
+- [ ] ResearchPanel displays correct progress and level
+- [ ] Save/load preserves research state
+- [ ] Prestige resets research levels and XP
+- [ ] Multiple research tracks work independently
+- [ ] Buff purchase correctly affects XP gain
+
+---
+
+## Dependencies
+
+- `CurrencyGenerator` must emit `production_tick` signal
+- `GeneratorBuffData` must support `RESEARCH_XP_MULTIPLIER` kind
+- `LevelGameState` must support buff tracking and signals
+- Save format version must be updated

core/research/research_catalogue.gd

@@ -0,0 +1,19 @@
+class_name ResearchCatalogue
+extends Resource
+
+@export var research_entries: Array[ResearchData] = []
+
+func get_research_by_id(research_id: StringName) -> ResearchData:
+	for entry in research_entries:
+		if entry.id == research_id:
+			return entry
+	return null
+
+func get_research_by_generator_id(generator_id: StringName) -> ResearchData:
+	for entry in research_entries:
+		if entry.generator_id == generator_id:
+			return entry
+	return null
+
+func get_all_research() -> Array[ResearchData]:
+	return research_entries.duplicate()

core/research/research_catalogue.gd.uid

@@ -0,0 +1 @@
+uid://d2v6t6w2todfy

core/research/research_data.gd

@@ -0,0 +1,66 @@
+class_name ResearchData
+extends Resource
+
+@export var id: StringName = &""
+@export var generator_id: StringName = &""
+@export var name: String = ""
+@export_multiline var description: String = ""
+@export var icon: Texture2D
+
+## XP Configuration
+@export var xp_per_currency_produced: float = 0.01
+@export var base_xp_required: float = 100.0
+@export var xp_growth_multiplier: float = 1.5
+
+## Multiplier Configuration
+@export var base_multiplier: float = 1.0
+@export var multiplier_per_level: float = 0.1
+
+## Associated Buff (single buff per research track)
+@export var associated_buff_id: StringName = &""
+
+func get_xp_required_for_level(level: int) -> float:
+	return base_xp_required * pow(xp_growth_multiplier, float(maxi(level - 1, 0)))
+
+func get_xp_required_for_level_big(level: int) -> BigNumber:
+	var float_val: float = base_xp_required * pow(xp_growth_multiplier, float(maxi(level - 1, 0)))
+	return BigNumber.from_float(float_val)
+
+func get_total_xp_for_level(level: int) -> BigNumber:
+	if level <= 0:
+		return BigNumber.new(0.0, 0)
+	var total: BigNumber = BigNumber.new(0.0, 0)
+	for l in range(1, level + 1):
+		total = total.add(get_xp_required_for_level_big(l))
+	return total
+
+func get_level_for_xp(xp: BigNumber) -> int:
+	if xp.mantissa == 0.0:
+		return 0
+	var level: int = 0
+	while true:
+		var next_xp: BigNumber = get_total_xp_for_level(level + 1)
+		if xp.compare_to(next_xp) < 0:
+			break
+		level += 1
+	return level
+
+func get_multiplier_for_level(level: int) -> float:
+	return base_multiplier + (multiplier_per_level * float(maxi(level, 0)))
+
+func get_xp_progress(xp: BigNumber) -> float:
+	if xp.mantissa == 0.0:
+		return 0.0
+	var current_level: int = get_level_for_xp(xp)
+	if current_level < 0:
+		return 0.0
+	
+	var xp_at_current_level: BigNumber = get_total_xp_for_level(current_level)
+	var xp_needed_for_next: BigNumber = get_xp_required_for_level_big(current_level + 1)
+	var xp_in_current_level: BigNumber = xp.subtract(xp_at_current_level)
+	
+	if xp_needed_for_next.mantissa == 0.0:
+		return 1.0
+	
+	var ratio: float = (xp_in_current_level.mantissa / xp_needed_for_next.mantissa) * pow(10.0, float(xp_in_current_level.exponent - xp_needed_for_next.exponent))
+	return clampf(ratio, 0.0, 1.0)

core/research/research_data.gd.uid

@@ -0,0 +1 @@
+uid://m7baywrfnpn0

core/research/research_panel.gd

@@ -0,0 +1,60 @@
+class_name ResearchPanel
+extends PanelContainer
+
+const RESEARCH_ROW_SCENE: PackedScene = preload("res://core/research/research_row.tscn")
+
+@onready var _title_label: Label = $ScrollContainer/VBoxContainer/TitleLabel
+@onready var _research_rows_container: VBoxContainer = $ScrollContainer/VBoxContainer/ResearchRows
+
+var _game_state: LevelGameState
+var _research_rows: Dictionary = {}
+
+func _ready() -> void:
+	_game_state = find_parent("LevelGameState")
+	if _game_state == null:
+		push_error("ResearchPanel: Could not find LevelGameState parent")
+		return
+	
+	_game_state.research_xp_changed.connect(_on_research_xp_changed)
+	_game_state.research_level_up.connect(_on_research_level_up)
+	
+	_build_research_rows()
+	_refresh_all()
+
+func _build_research_rows() -> void:
+	for child in _research_rows_container.get_children():
+		child.queue_free()
+	_research_rows.clear()
+	
+	if _game_state.research_catalogue:
+		for research in _game_state.research_catalogue.get_all_research():
+			var row: ResearchRow = RESEARCH_ROW_SCENE.instantiate()
+			_research_rows_container.add_child(row)
+			row.setup(research)
+			_research_rows[research.id] = row
+
+func _refresh_all() -> void:
+	for row in _research_rows.values():
+		_refresh_row(row)
+
+func _refresh_row(row: ResearchRow) -> void:
+	var research_id: StringName = row.get_research_id()
+	var xp: BigNumber = _game_state.get_research_xp(research_id)
+	var level: int = _game_state.get_research_level(research_id)
+	var research: ResearchData = _game_state.research_catalogue.get_research_by_id(research_id)
+	
+	if research != null:
+		var progress: float = research.get_xp_progress(xp)
+		var multiplier: float = research.get_multiplier_for_level(level)
+		var xp_current: BigNumber = xp.subtract(research.get_total_xp_for_level(level))
+		var xp_needed: BigNumber = research.get_xp_required_for_level_big(level + 1)
+		
+		row.update_display(level, progress, multiplier, xp_current, xp_needed)
+
+func _on_research_xp_changed(research_id: StringName, _new_xp: BigNumber) -> void:
+	if _research_rows.has(research_id):
+		_refresh_row(_research_rows[research_id])
+
+func _on_research_level_up(research_id: StringName, _old_level: int, _new_level: int) -> void:
+	if _research_rows.has(research_id):
+		_refresh_row(_research_rows[research_id])

core/research/research_panel.gd.uid

@@ -0,0 +1 @@
+uid://fdl7ftxw8w1e

core/research/research_panel.tscn

@@ -0,0 +1,26 @@
+[gd_scene format=3 uid="uid://dd8roif0mqirl"]
+
+[ext_resource type="Script" uid="uid://fdl7ftxw8w1e" path="res://core/research/research_panel.gd" id="1_script"]
+[ext_resource type="PackedScene" uid="uid://bpo8pl5tipav" path="res://core/research/research_row.tscn" id="2_3m5ee"]
+
+[node name="ResearchPanel" type="PanelContainer" unique_id=1105274967]
+custom_minimum_size = Vector2(400, 100)
+offset_right = 400.0
+offset_bottom = 100.0
+script = ExtResource("1_script")
+
+[node name="ScrollContainer" type="ScrollContainer" parent="." unique_id=1099596602]
+layout_mode = 2
+
+[node name="VBoxContainer" type="VBoxContainer" parent="ScrollContainer" unique_id=692886617]
+layout_mode = 2
+
+[node name="TitleLabel" type="Label" parent="ScrollContainer/VBoxContainer" unique_id=1565843659]
+layout_mode = 2
+text = "Research"
+
+[node name="ResearchRows" type="VBoxContainer" parent="ScrollContainer/VBoxContainer" unique_id=1200240263]
+layout_mode = 2
+
+[node name="ResearchRow" parent="ScrollContainer/VBoxContainer/ResearchRows" unique_id=245375198 instance=ExtResource("2_3m5ee")]
+layout_mode = 2

core/research/research_row.gd

@@ -0,0 +1,74 @@
+class_name ResearchRow
+extends HBoxContainer
+
+@onready var _name_label: Label = $VBoxContainer/NameLabel
+@onready var _level_label: Label = $VBoxContainer/HBoxContainer/LevelLabel
+@onready var _progress_bar: ProgressBar = $VBoxContainer/HBoxContainer/ProgressBar
+@onready var _multiplier_label: Label = $VBoxContainer/HBoxContainer/MultiplierLabel
+@onready var _buff_label: Label = $VBoxContainer/HBoxContainer/BuffLabel
+
+var _research: ResearchData
+var _game_state: LevelGameState
+
+func _ready() -> void:
+	_game_state = find_parent("LevelGameState")
+	if _game_state == null:
+		push_error("ResearchRow: Could not find LevelGameState parent")
+		return
+	
+	_game_state.research_xp_changed.connect(_on_research_xp_changed)
+	_game_state.research_level_up.connect(_on_research_level_up)
+
+func setup(research: ResearchData) -> void:
+	_research = research
+	if _name_label:
+		_name_label.text = research.name
+
+func get_research_id() -> StringName:
+	if _research == null:
+		return &""
+	return _research.id
+
+func update_display(level: int, progress: float, multiplier: float, xp_current: BigNumber, xp_needed: BigNumber) -> void:
+	if _level_label:
+		_level_label.text = "Level %d" % level
+	
+	if _progress_bar:
+		_progress_bar.value = progress * 100
+	
+	if _multiplier_label:
+		_multiplier_label.text = "+%d%%" % int((multiplier - 1.0) * 100)
+	
+	if _buff_label and _research != null:
+		if not _research.associated_buff_id.is_empty():
+			var buff: GeneratorBuffData = _game_state.get_buff(_research.associated_buff_id)
+			if buff != null and _game_state.is_buff_active(buff.id):
+				var buff_level: int = _game_state.get_buff_level(buff.id)
+				var effect: float = buff.get_effect_multiplier(buff_level) - 1.0
+				_buff_label.text = "%s: +%d%% XP" % [buff.text, int(effect * 100)]
+			else:
+				_buff_label.text = ""
+		else:
+			_buff_label.text = ""
+
+func _on_research_xp_changed(research_id: StringName, _new_xp: BigNumber) -> void:
+	if _research != null and research_id == _research.id:
+		_update_from_state()
+
+func _on_research_level_up(research_id: StringName, _old_level: int, _new_level: int) -> void:
+	if _research != null and research_id == _research.id:
+		_update_from_state()
+
+func _update_from_state() -> void:
+	if _research == null or _game_state == null:
+		return
+	
+	var xp: BigNumber = _game_state.get_research_xp(_research.id)
+	var level: int = _game_state.get_research_level(_research.id)
+	
+	var progress: float = _research.get_xp_progress(xp)
+	var multiplier: float = _research.get_multiplier_for_level(level)
+	var xp_current: BigNumber = xp.subtract(_research.get_total_xp_for_level(level))
+	var xp_needed: BigNumber = _research.get_xp_required_for_level_big(level + 1)
+	
+	update_display(level, progress, multiplier, xp_current, xp_needed)

core/research/research_row.gd.uid

@@ -0,0 +1 @@
+uid://gk3mr3k5yvp7

core/research/research_row.tscn

@@ -0,0 +1,38 @@
+[gd_scene format=3 uid="uid://bpo8pl5tipav"]
+
+[ext_resource type="Script" uid="uid://gk3mr3k5yvp7" path="res://core/research/research_row.gd" id="1_script"]
+
+[node name="ResearchRow" type="HBoxContainer" unique_id=810714290]
+mouse_filter = 2
+script = ExtResource("1_script")
+
+[node name="Icon" type="TextureRect" parent="." unique_id=1376308659]
+layout_mode = 2
+size_flags_horizontal = 0
+size_flags_vertical = 0
+
+[node name="VBoxContainer" type="VBoxContainer" parent="." unique_id=468422769]
+layout_mode = 2
+
+[node name="NameLabel" type="Label" parent="VBoxContainer" unique_id=1742937834]
+layout_mode = 2
+text = "Research Name"
+
+[node name="HBoxContainer" type="HBoxContainer" parent="VBoxContainer" unique_id=819270678]
+layout_mode = 2
+alignment = 2
+
+[node name="LevelLabel" type="Label" parent="VBoxContainer/HBoxContainer" unique_id=1108328348]
+layout_mode = 2
+text = "Level 0"
+
+[node name="ProgressBar" type="ProgressBar" parent="VBoxContainer/HBoxContainer" unique_id=1855503166]
+custom_minimum_size = Vector2(200, 0)
+layout_mode = 2
+
+[node name="MultiplierLabel" type="Label" parent="VBoxContainer/HBoxContainer" unique_id=135310321]
+layout_mode = 2
+text = "+0%"
+
+[node name="BuffLabel" type="Label" parent="VBoxContainer/HBoxContainer" unique_id=2124734446]
+layout_mode = 2

core/research/research_xp_tracker.gd

@@ -0,0 +1,48 @@
+class_name ResearchXPTracker
+extends Node
+
+@export var game_state: LevelGameState
+
+signal research_xp_changed(research_id: StringName, new_xp: BigNumber)
+signal research_level_up(research_id: StringName, old_level: int, new_level: int)
+
+func add_xp_with_buffs(research_id: StringName, base_xp: BigNumber) -> BigNumber:
+	if game_state == null:
+		return BigNumber.new(0.0, 0)
+	
+	var buff_multiplier: float = game_state.get_research_xp_multiplier(research_id)
+	var multiplier_bn: BigNumber = BigNumber.from_float(buff_multiplier)
+	var actual_xp: BigNumber = base_xp.multiply(multiplier_bn)
+	
+	game_state.add_research_xp(research_id, actual_xp)
+	
+	return actual_xp
+
+func _on_generator_produced(generator_id: StringName, _amount: Variant) -> void:
+	var research: ResearchData = _get_research_for_generator(generator_id)
+	if research == null:
+		return
+	
+	var research_catalogue: ResearchCatalogue = game_state.research_catalogue
+	if research_catalogue == null:
+		return
+	
+	research = research_catalogue.get_research_by_generator_id(generator_id)
+	if research == null:
+		return
+	
+	var amount_big: BigNumber = _amount
+	var amount_float: float = amount_big.mantissa * pow(10.0, float(amount_big.exponent))
+	if amount_float <= 0.0:
+		return
+	
+	var base_xp: BigNumber = BigNumber.from_float(research.xp_per_currency_produced * amount_float)
+	if base_xp.mantissa <= 0.0:
+		return
+	
+	add_xp_with_buffs(research.id, base_xp)
+
+func _get_research_for_generator(generator_id: StringName) -> ResearchData:
+	if game_state == null or game_state.research_catalogue == null:
+		return null
+	return game_state.research_catalogue.get_research_by_generator_id(generator_id)

core/research/research_xp_tracker.gd.uid

@@ -0,0 +1 @@
+uid://bv3a4utlnn2fg