feat(ui): unified dialogue log with overheard NPC conversations (#535)

Refactors dialogue box into a scrolling conversation log. All dialogue
(player-NPC and overheard NPC-NPC) flows chronologically, oldest at top.
Player response options at the bottom during active conversations.

- Entries expire after configurable timeout (equal for all message types)
- Walk-away clears options but preserves log entries (fair information)
- Per-character name colors from dialogue-theme.yaml (hash-indexed palette)
- Overheard lines render at 90% opacity (D-078)
- Protocol decode for conversation_events + conversation_ended
- GameState fields for conversation_events, conversation_ended, dialogue_response
- Mock Mira/Soren NPC-NPC conversation in test snapshot
- Also wires #511 debug overlay into main.gd and main.tscn

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/data/dialogue-theme.yaml

@@ -0,0 +1,47 @@
+# Dialogue Log Theme — The Settled Reach
+#
+# Ticket: #535 | Sprint: 14
+# Colors and timing for the unified dialogue log panel.
+# Loaded by dialogue_box.gd at runtime.
+
+# ============================================================
+# PLAYER COLOR
+# Fixed color for the player's name in dialogue log entries.
+# ============================================================
+player_color: "#e0e8ff"
+
+# ============================================================
+# NPC COLOR PALETTE
+# 8 distinct colors for NPC names. Indexed by hash(npc_name) % 8.
+# Must be readable on a dark semi-transparent panel background.
+# ============================================================
+npc_colors:
+  0: "#4a9ebb"  # teal
+  1: "#6bc9a6"  # green
+  2: "#e8c547"  # amber
+  3: "#d49e5d"  # warm orange
+  4: "#b586d4"  # lavender
+  5: "#d45d5d"  # muted red
+  6: "#5daa7d"  # forest
+  7: "#7daccc"  # sky blue
+
+# ============================================================
+# TEXT COLORS
+# Arrow separator and speech text color.
+# ============================================================
+arrow_color: "#8890a0"
+speech_color: "#c8d0e0"
+
+# ============================================================
+# PASSIVE (OVERHEARD) OPACITY
+# Base opacity multiplier for non-player-centric lines.
+# 1.0 = full opacity, 0.0 = invisible.
+# ============================================================
+passive_opacity: "0.9"
+
+# ============================================================
+# ENTRY TIMING
+# All entry types share the same lifetime and fade duration.
+# ============================================================
+entry_lifetime_seconds: "15.0"
+entry_fade_seconds: "3.0"

client/scenes/main.tscn

@@ -1,4 +1,4 @@
-[gd_scene load_steps=22 format=3 uid="uid://bswrmh7w8dbgm"]
+[gd_scene load_steps=23 format=3 uid="uid://bswrmh7w8dbgm"]
 
 [ext_resource type="Script" path="res://scripts/main.gd" id="1_main"]
 [ext_resource type="Script" path="res://scripts/rendering/world_renderer.gd" id="2_world"]
@@ -21,6 +21,7 @@
 [ext_resource type="PackedScene" path="res://ui/checklist_overlay.tscn" id="18_checklist"]
 [ext_resource type="PackedScene" path="res://ui/bug_report_dialog.tscn" id="19_bugreport"]
 [ext_resource type="PackedScene" path="res://ui/settings_dialog.tscn" id="21_settings"]
+[ext_resource type="Script" path="res://scripts/ui/debug_overlay.gd" id="22_debug"]
 
 [node name="Game" type="Node2D"]
 script = ExtResource("1_main")
@@ -152,6 +153,16 @@ layer = 20
 ; D-065: Inventory grid — 3x3, bottom-right, 40x40px, 1-9 hotkeys
 [node name="InventoryGrid" parent="UILayer" instance=ExtResource("12_inv")]
 
+; #511: F3 debug overlay — real-time game state, toggled by F3
+[node name="DebugOverlay" type="Control" parent="UILayer"]
+anchors_preset = 0
+offset_left = 16
+offset_top = 120
+offset_right = 400
+offset_bottom = 400
+mouse_filter = 2
+script = ExtResource("22_debug")
+
 ; D-056: Cursor state machine — insert-styled geometric cursor, topmost in UILayer
 [node name="CursorRenderer" type="Node2D" parent="UILayer"]
 script = ExtResource("10_cursor")

client/scripts/autoloads/game_state.gd

@@ -59,6 +59,11 @@ var rng_seed: Variant = null
 # v7 fields (#431, D-059/D-060)
 var pending_recognitions: Array = []  # [{entity_id, x, y, z, remaining_ticks, total_delay_ticks}]
 
+# v9 fields (#535, D-078): Overheard NPC-to-NPC conversations
+var conversation_events: Array = []  # [{speaker_id, target_id, speaker_name, target_name, occluded_line}]
+var conversation_ended: Array = []  # [{speaker_id, target_id}]
+var dialogue_response: Variant = null  # {line_id, text, speaker_entity_id} — NPC follow-up after player choice
+
 # #126, D-018: Medium-range sound events for fog-edge directional indicators.
 # Format: [{x, y, event_type, range_category}] — server sends current medium events per tick.
 var medium_sound_events: Array = []
@@ -169,6 +174,24 @@ func apply_snapshot(snapshot: Dictionary) -> void:
 	else:
 		pending_recognitions = []
 
+	# v9: conversation_events (#535, D-078) — overheard NPC-to-NPC lines
+	if snapshot.has("conversation_events") and snapshot.conversation_events is Array:
+		conversation_events = snapshot.conversation_events
+	else:
+		conversation_events = []
+
+	# v9: conversation_ended (#535, D-078) — pairs whose conversation ended
+	if snapshot.has("conversation_ended") and snapshot.conversation_ended is Array:
+		conversation_ended = snapshot.conversation_ended
+	else:
+		conversation_ended = []
+
+	# v9: dialogue_response (#535, D-028) — NPC follow-up after player choice
+	if snapshot.has("dialogue_response") and snapshot.dialogue_response is Dictionary:
+		dialogue_response = snapshot.dialogue_response
+	else:
+		dialogue_response = null
+
 	# v8: gauntlet mode (#496) — room_id and gauntlet_mode
 	if snapshot.has("gauntlet_mode") and snapshot.gauntlet_mode == true:
 		gauntlet_mode = true

client/scripts/autoloads/sim_bridge.gd

@@ -396,6 +396,37 @@ func _test_snapshot() -> Dictionary:
 			"total_delay_ticks": total_delay,
 		})
 
+	# #535: Mock overheard NPC-NPC conversation (D-078)
+	# Two NPCs (Mira and Soren) trade lines every 5 ticks starting at tick 3.
+	# Conversation ends after 6 exchanges (~30 ticks).
+	var conv_events: Array = []
+	var conv_ended: Array = []
+	var conv_start := 3
+	var conv_lines := [
+		{"speaker": "Mira", "target": "Soren", "line": "The cargo manifests don't add up. Three containers unaccounted for."},
+		{"speaker": "Soren", "target": "Mira", "line": "Could be a logging error. Happens every... cycle."},
+		{"speaker": "Mira", "target": "Soren", "line": "Not like this. Someone moved them after... check."},
+		{"speaker": "Soren", "target": "Mira", "line": "You're reading too much into it. The docks are... these days."},
+		{"speaker": "Mira", "target": "Soren", "line": "Then explain the weight discrepancy. Two hundred kilos... just gone."},
+		{"speaker": "Soren", "target": "Mira", "line": "Fine. I'll pull the bay... tonight. But keep this between us."},
+	]
+	var conv_tick_interval := 5
+	var conv_total_ticks := conv_lines.size() * conv_tick_interval
+	if _test_tick >= conv_start and _test_tick < conv_start + conv_total_ticks:
+		var conv_index := (_test_tick - conv_start) / conv_tick_interval
+		var within_tick := (_test_tick - conv_start) % conv_tick_interval
+		if within_tick == 0 and conv_index < conv_lines.size():
+			var cl: Dictionary = conv_lines[conv_index]
+			conv_events.append({
+				"speaker_id": 10,
+				"target_id": 11,
+				"speaker_name": cl.speaker,
+				"target_name": cl.target,
+				"occluded_line": cl.line,
+			})
+	elif _test_tick == conv_start + conv_total_ticks:
+		conv_ended.append({"speaker_id": 10, "target_id": 11})
+
 	return {
 		"tick": _test_tick,
 		"version": Protocol.PROTOCOL_VERSION,
@@ -417,6 +448,8 @@ func _test_snapshot() -> Dictionary:
 		"current_dialogue": dialogue,
 		"pending_recognitions": pending_recs,
 		"gauntlet_mode": _test_gauntlet_mode,
+		"conversation_events": conv_events,
+		"conversation_ended": conv_ended,
 	}
 
 # Generate a small test room: 8x6 room with walls, a door, and floor

client/scripts/main.gd

@@ -14,10 +14,12 @@ extends Node2D
 @onready var cursor_renderer = $UILayer/CursorRenderer  # D-056: z-layer 7
 @onready var gauntlet_hud = $UILayer/GauntletHUD  # #496: room timer + personal bests
 @onready var checklist_overlay = $UILayer/ChecklistOverlay  # #503: auto-checklist progress
+@onready var debug_overlay = $UILayer/DebugOverlay  # #511: F3 debug overlay
 @onready var bug_report_dialog = $ModalLayer/BugReportDialog  # #495: F12 WRONG button
 @onready var settings_dialog = $ModalLayer/SettingsDialog     # #528: audio settings (ESC/OPEN_MENU)
 
 var _last_dialogue_npc_id: int = -1  # D-064: NPC entity_id for WalkAway input
+var _last_dialogue_npc_name: String = ""  # #535: NPC name for dialogue_response attribution
 var _camera_anchored: bool = false
 var _last_monologue_tick: int = -1       # Prevent re-consuming monologue when same tick polled twice
 var _last_dialogue_tick: int = -1
@@ -130,6 +132,10 @@ func _process(_delta: float) -> void:
 		if checklist_overlay and checklist_overlay.has_method("update_from_state"):
 			checklist_overlay.update_from_state()
 
+		# #511: Update debug overlay (F3 toggle, dev tool)
+		if debug_overlay and debug_overlay.has_method("update_from_state"):
+			debug_overlay.update_from_state()
+
 		# D-018 #125: Play close-range sound events via positional 2D audio
 		_play_close_sound_events()
 
@@ -146,6 +152,11 @@ func _process(_delta: float) -> void:
 		# D-061: Show dialogue if server sent one this tick (#434)
 		_consume_dialogue()
 
+		# #535: Consume overheard conversation events and responses
+		_consume_conversation_events()
+		_consume_conversation_ended()
+		_consume_dialogue_response()
+
 	# Track camera to player position every frame (D-015: locked, no panning)
 	if _camera_anchored:
 		camera.global_position = GameState.player_position * Constants.TILE_SIZE
@@ -316,6 +327,7 @@ func _consume_dialogue() -> void:
 	_last_dialogue_tick = GameState.current_tick
 	var dlg: Dictionary = GameState.current_dialogue
 	_last_dialogue_npc_id = dlg.get("npc_entity_id", -1)
+	_last_dialogue_npc_name = dlg.get("npc_name", "")
 	dialogue_box.show_dialogue(
 		dlg.get("npc_name", ""),
 		dlg.get("speech", ""),
@@ -324,6 +336,34 @@ func _consume_dialogue() -> void:
 	GameState.current_dialogue = null
 
 
+# #535: Consume overheard NPC-NPC conversation events (D-078).
+# Each event carries pre-occluded text — render verbatim in the dialogue log.
+func _consume_conversation_events() -> void:
+	if not dialogue_box:
+		return
+	for event in GameState.conversation_events:
+		dialogue_box.append_conversation_event(event)
+	GameState.conversation_events = []
+
+
+# #535: Handle conversation_ended events — notify dialogue box to stop tracking pairs.
+func _consume_conversation_ended() -> void:
+	if not dialogue_box:
+		return
+	for event in GameState.conversation_ended:
+		dialogue_box.on_conversation_ended(event)
+	GameState.conversation_ended = []
+
+
+# #535: Consume dialogue_response — NPC follow-up line after player picks an option.
+func _consume_dialogue_response() -> void:
+	if GameState.dialogue_response == null or not dialogue_box:
+		return
+	var dr: Dictionary = GameState.dialogue_response
+	dialogue_box.append_dialogue_response(_last_dialogue_npc_name, dr.get("text", ""))
+	GameState.dialogue_response = null
+
+
 # D-061: Handle dialogue option selection → send to server
 func _on_dialogue_option_selected(response_id: String, text: String) -> void:
 	SimBridge.send_input({

client/scripts/protocol/protocol.gd

@@ -180,6 +180,32 @@ static func decode_snapshot(bytes: PackedByteArray) -> Variant:
 			"speaker_entity_id": int(raw_dr.get("speaker_entity_id", -1)),
 		}
 
+	# v9: conversation_events (#535, D-078) — overheard NPC-to-NPC dialogue lines.
+	# Each event carries pre-occluded text plus speaker/target attribution.
+	var conversation_events: Array = []
+	var raw_conv_events: Variant = raw.get("conversation_events")
+	if raw_conv_events is Array:
+		for raw_ce in raw_conv_events:
+			if raw_ce is Dictionary and raw_ce.has("occluded_line"):
+				conversation_events.append({
+					"speaker_id": int(raw_ce.get("speaker_id", 0)),
+					"target_id": int(raw_ce.get("target_id", 0)),
+					"speaker_name": str(raw_ce.get("speaker_name", "")),
+					"target_name": str(raw_ce.get("target_name", "")),
+					"occluded_line": str(raw_ce["occluded_line"]),
+				})
+
+	# v9: conversation_ended (#535, D-078) — pairs whose conversation ended this tick.
+	var conversation_ended: Array = []
+	var raw_conv_ended: Variant = raw.get("conversation_ended")
+	if raw_conv_ended is Array:
+		for raw_end in raw_conv_ended:
+			if raw_end is Dictionary:
+				conversation_ended.append({
+					"speaker_id": int(raw_end.get("speaker_id", 0)),
+					"target_id": int(raw_end.get("target_id", 0)),
+				})
+
 	return {
 		"tick": tick,
 		"entities": entities,
@@ -195,6 +221,8 @@ static func decode_snapshot(bytes: PackedByteArray) -> Variant:
 		"current_dialogue": current_dialogue,
 		"dialogue_response": dialogue_response,
 		"pending_recognitions": pending_recognitions,
+		"conversation_events": conversation_events,
+		"conversation_ended": conversation_ended,
 	}
 
 

client/ui/dialogue_box.gd

@@ -1,28 +1,49 @@
 extends Control
 
 # Dialogue box — D-061: bottom screen, max 20% height, no portraits.
+# #535: Unified conversation log — player dialogue and overheard NPC-NPC conversations
+# flow chronologically. Oldest at top, scrolls up. Options at bottom.
+#
 # InsertOverlay (CanvasLayer 10, z-layer 6) — diegetic, insert-styled.
-# NPC speech top, player response options below, left-aligned.
-# Max 3 visible options. No close button — walk-away (WASD) or option select only.
-# Auto-pause in single-player when dialogue is open (D-061).
 # D-063: Confrontation options render italic, trigger monologue beat before send.
+# D-064: Walk-away via WASD dismisses active conversation (log entries persist).
+# D-078: Overheard NPC-NPC lines shown at reduced opacity, no response options.
 
 signal option_selected(response_id: String, text: String)
 signal dialogue_dismissed  # Walk-away or conversation end
 signal confrontation_monologue(text: String, duration: float)  # D-063: beat monologue
 
 @onready var panel: PanelContainer = $PanelContainer
-@onready var npc_speech: RichTextLabel = $PanelContainer/MarginContainer/VBoxContainer/NpcSpeech
+@onready var dialogue_log: RichTextLabel = $PanelContainer/MarginContainer/VBoxContainer/DialogueLog
 @onready var options_container: VBoxContainer = $PanelContainer/MarginContainer/VBoxContainer/OptionsContainer
 
+# -- Log state --
+var _log_entries: Array[Dictionary] = []  # {speaker, target, text, is_passive, timestamp_msec}
+var _active_overheard: Dictionary = {}  # "speaker_id:target_id" -> true
+var _in_player_conversation: bool = false
+
+# -- Option state --
+var _option_controls: Array[Control] = []
+var _option_response_ids: Array[String] = []
+var _option_texts: Array[String] = []
+var _option_is_confrontation: Array[bool] = []
+var _npc_name: String = ""
+
+# -- UI state --
 var _is_showing: bool = false
 var _active_tween: Tween = null
 var _beat_tween: Tween = null  # D-063: confrontation beat delay
-var _option_controls: Array[Control] = []
-var _option_response_ids: Array[String] = []  # response_id per option, same index
-var _option_texts: Array[String] = []  # raw display text per option
-var _option_is_confrontation: Array[bool] = []  # confrontation flag per option
-var _npc_name: String = ""
+
+# -- Theme (loaded from data/dialogue-theme.yaml) --
+var _player_color: Color = Color("#e0e8ff")
+var _npc_colors: Array[Color] = []
+var _arrow_color: Color = Color("#8890a0")
+var _speech_color: Color = Color("#c8d0e0")
+var _passive_opacity: float = 0.9
+var _entry_lifetime: float = 15.0
+var _entry_fade: float = 3.0
+
+const THEME_PATH: String = "res://data/dialogue-theme.yaml"
 
 const FADE_IN: float = 0.2
 const FADE_OUT: float = 0.3  # D-064: 300ms fade on walk-away
@@ -32,6 +53,7 @@ const MAX_WIDTH_PX: float = Constants.DIALOGUE_MAX_WIDTH  # D-076: 640px (OQ-29)
 const CONFRONTATION_BEAT_DURATION: float = 1.5  # D-063: pause before sending
 const CONFRONTATION_DIM_ALPHA: float = 0.7  # D-063: dialogue box dims during beat
 const CONFRONTATION_MONOLOGUE_KEY: String = "dialogue.confrontation_beat"
+const PLAYER_NAME: String = "You"
 
 # D-064: movement actions that trigger walk-away
 const _WALK_AWAY_ACTIONS: Array[StringName] = [
@@ -45,26 +67,78 @@ func _ready() -> void:
 	visible = false
 	_is_showing = false
 	mouse_filter = Control.MOUSE_FILTER_IGNORE
+	_load_theme()
 	_update_layout()
 	get_viewport().size_changed.connect(_update_layout)
 
 
+func _process(_delta: float) -> void:
+	_expire_entries()
+
+
 func _unhandled_input(event: InputEvent) -> void:
 	if not _is_showing:
 		return
+	if not _in_player_conversation:
+		return
 
-	# D-064: WASD during dialogue → walk-away, 300ms fade
+	# D-064: WASD during active player dialogue → walk-away
 	if event is InputEventKey and event.pressed:
 		for action in _WALK_AWAY_ACTIONS:
 			if event.is_action_pressed(action):
 				get_viewport().set_input_as_handled()
 				_cancel_beat()
-				hide_dialogue()
+				_end_player_conversation()
 				dialogue_dismissed.emit()
 				return
 
 
-# Responsive layout — clamps width to MAX_WIDTH_PX and height to 20% viewport.
+# -- Theme loading --
+
+func _load_theme() -> void:
+	# Default NPC palette in case file not found
+	_npc_colors = [
+		Color("#4a9ebb"), Color("#6bc9a6"), Color("#e8c547"), Color("#d49e5d"),
+		Color("#b586d4"), Color("#d45d5d"), Color("#5daa7d"), Color("#7daccc"),
+	]
+
+	if not FileAccess.file_exists(THEME_PATH):
+		push_warning("DialogueBox: theme file not found: %s — using defaults" % THEME_PATH)
+		return
+
+	var file := FileAccess.open(THEME_PATH, FileAccess.READ)
+	if file == null:
+		return
+	var text := file.get_as_text()
+	file.close()
+
+	var strings := UIStrings._parse_yaml(text)
+
+	if strings.has("player_color"):
+		_player_color = Color(strings["player_color"])
+	if strings.has("arrow_color"):
+		_arrow_color = Color(strings["arrow_color"])
+	if strings.has("speech_color"):
+		_speech_color = Color(strings["speech_color"])
+	if strings.has("passive_opacity"):
+		_passive_opacity = float(strings["passive_opacity"])
+	if strings.has("entry_lifetime_seconds"):
+		_entry_lifetime = float(strings["entry_lifetime_seconds"])
+	if strings.has("entry_fade_seconds"):
+		_entry_fade = float(strings["entry_fade_seconds"])
+
+	# Load NPC colors from indexed keys (npc_colors.0 through npc_colors.7)
+	var loaded_colors: Array[Color] = []
+	for i in range(16):  # support up to 16 palette entries
+		var key := "npc_colors.%d" % i
+		if strings.has(key):
+			loaded_colors.append(Color(strings[key]))
+	if loaded_colors.size() > 0:
+		_npc_colors = loaded_colors
+
+
+# -- Responsive layout --
+
 func _update_layout() -> void:
 	var vp := get_viewport_rect().size
 	var max_h := vp.y * MAX_HEIGHT_RATIO
@@ -74,26 +148,128 @@ func _update_layout() -> void:
 	panel.offset_top = -max_h
 
 
-# Show dialogue with NPC speech and response options.
-# npc_name: who is speaking (displayed as prefix)
-# speech: the NPC's dialogue text
-# options: Array of {text, response_id, priority, confrontation} — sorted by priority, max 3 shown.
-#          D-062: locked options are invisible (server filters before sending).
-#          D-063: confrontation options render italic.
+# -- Log entry management --
+
+## Append a dialogue line to the log.
+## speaker/target: display names. text: the spoken line.
+## is_passive: true for overheard NPC-NPC (renders at reduced opacity).
+func append_line(speaker: String, target: String, text: String, is_passive: bool = false) -> void:
+	_log_entries.append({
+		"speaker": speaker,
+		"target": target,
+		"text": text,
+		"is_passive": is_passive,
+		"timestamp_msec": Time.get_ticks_msec(),
+	})
+	_rebuild_log()
+	_ensure_visible()
+
+
+## Append an overheard conversation event (D-078).
+func append_conversation_event(event: Dictionary) -> void:
+	var speaker: String = event.get("speaker_name", "?")
+	var target: String = event.get("target_name", "?")
+	var text: String = event.get("occluded_line", "")
+	if text.is_empty():
+		return
+	var pair_key := "%s:%s" % [event.get("speaker_id", 0), event.get("target_id", 0)]
+	_active_overheard[pair_key] = true
+	append_line(speaker, target, text, true)
+
+
+## Handle conversation_ended — remove pair from active tracking.
+func on_conversation_ended(event: Dictionary) -> void:
+	var pair_key := "%s:%s" % [event.get("speaker_id", 0), event.get("target_id", 0)]
+	_active_overheard.erase(pair_key)
+	# Also try the reverse pair
+	var reverse_key := "%s:%s" % [event.get("target_id", 0), event.get("speaker_id", 0)]
+	_active_overheard.erase(reverse_key)
+
+
+## Append the player's chosen response to the log.
+func append_player_line(target_npc: String, text: String) -> void:
+	append_line(PLAYER_NAME, target_npc, text, false)
+
+
+## Append an NPC follow-up line (from dialogue_response).
+func append_dialogue_response(npc_name: String, text: String) -> void:
+	append_line(npc_name, PLAYER_NAME, text, false)
+
+
+# -- Active player conversation --
+
+## Show dialogue with NPC speech and response options.
+## npc_name: who is speaking. speech: the NPC's line. options: player choices.
 func show_dialogue(npc_name: String, speech: String, options: Array = []) -> void:
 	_npc_name = npc_name
 	_cancel_beat()
+	_in_player_conversation = true
 
-	# NPC speech — name prefix in bold
-	if npc_name.is_empty():
-		npc_speech.text = speech
-	else:
-		npc_speech.text = "[b]%s:[/b] %s" % [npc_name, speech]
+	# Append NPC's line to the log
+	if not speech.is_empty():
+		append_line(npc_name, PLAYER_NAME, speech, false)
 
-	# Clear old options
+	# Clear old options and show new ones
 	_clear_options()
+	_show_options(options)
 
-	# Sort by priority ascending, cap at MAX_OPTIONS (D-061: max 3 visible)
+	# Show panel
+	_ensure_visible()
+	mouse_filter = Control.MOUSE_FILTER_STOP
+	GameState.dialogue_active = true  # D-064: block movement while in conversation
+
+	# D-069: Dialogue dip
+	AudioManager.apply_dip("dialogue")
+
+	# D-061: auto-pause in single-player
+	SimBridge.send_input({"action": InputMapper.Action.PAUSE, "timestamp_msec": Time.get_ticks_msec()})
+
+
+## End active player conversation — clears options but preserves log.
+func _end_player_conversation() -> void:
+	_in_player_conversation = false
+	_clear_options()
+	mouse_filter = Control.MOUSE_FILTER_IGNORE
+
+	# D-069: Clear dialogue/confrontation dip
+	AudioManager.clear_dip()
+
+	# D-061: unpause
+	SimBridge.send_input({"action": InputMapper.Action.UNPAUSE, "timestamp_msec": Time.get_ticks_msec()})
+
+	GameState.dialogue_active = false
+
+
+## Hide the entire panel with fade.
+func hide_dialogue() -> void:
+	if not _is_showing:
+		return
+
+	if _in_player_conversation:
+		_end_player_conversation()
+
+	_is_showing = false
+
+	if _active_tween and _active_tween.is_valid():
+		_active_tween.kill()
+	_active_tween = create_tween()
+	_active_tween.tween_property(panel, "modulate:a", 0.0, FADE_OUT)
+	_active_tween.tween_callback(func():
+		visible = false
+	)
+
+
+func is_dialogue_active() -> bool:
+	return _in_player_conversation or GameState.dialogue_active
+
+
+func has_active_entries() -> bool:
+	return _log_entries.size() > 0 or _in_player_conversation
+
+
+# -- Options --
+
+func _show_options(options: Array) -> void:
 	var sorted_opts: Array = options.duplicate()
 	sorted_opts.sort_custom(func(a, b): return a.get("priority", 0) < b.get("priority", 0))
 	var count := mini(sorted_opts.size(), MAX_OPTIONS)
@@ -103,7 +279,6 @@ func show_dialogue(npc_name: String, speech: String, options: Array = []) -> voi
 		var raw_text: String = opt.get("text", "")
 		var is_confrontation: bool = opt.get("confrontation", false)
 
-		# RichTextLabel for BBCode support (D-063: confrontation italic)
 		var label := RichTextLabel.new()
 		label.bbcode_enabled = true
 		label.fit_content = true
@@ -117,13 +292,11 @@ func show_dialogue(npc_name: String, speech: String, options: Array = []) -> voi
 		else:
 			label.text = raw_text
 
-		# Click handling
 		var idx := i
 		label.gui_input.connect(func(event: InputEvent):
 			if event is InputEventMouseButton and event.pressed and event.button_index == MOUSE_BUTTON_LEFT:
 				_on_option_pressed(idx)
 		)
-		# Hover color
 		label.mouse_entered.connect(_make_hover_on(label))
 		label.mouse_exited.connect(_make_hover_off(label))
 
@@ -133,56 +306,6 @@ func show_dialogue(npc_name: String, speech: String, options: Array = []) -> voi
 		_option_texts.append(raw_text)
 		_option_is_confrontation.append(is_confrontation)
 
-	# Show with fade
-	visible = true
-	mouse_filter = Control.MOUSE_FILTER_STOP
-	_is_showing = true
-	GameState.dialogue_active = true  # D-064: block movement while dialogue visible/fading
-
-	# D-069: Dialogue dip — reduce ambient noise to foreground conversation.
-	# Confrontation options REPLACE (not nest) this dip via apply_dip("confrontation")
-	# in _start_confrontation_beat(). hide_dialogue()'s clear_dip() restores to base
-	# volumes regardless of which profile was last active — intentional replacement semantics.
-	AudioManager.apply_dip("dialogue")
-
-	# D-061: auto-pause in single-player when dialogue opens
-	SimBridge.send_input({"action": InputMapper.Action.PAUSE, "timestamp_msec": Time.get_ticks_msec()})
-
-	if _active_tween and _active_tween.is_valid():
-		_active_tween.kill()
-	_active_tween = create_tween()
-	_active_tween.tween_property(panel, "modulate:a", 1.0, FADE_IN)
-
-
-# Hide dialogue with fade (D-064: 300ms)
-func hide_dialogue() -> void:
-	if not _is_showing:
-		return
-
-	_is_showing = false
-	mouse_filter = Control.MOUSE_FILTER_IGNORE
-
-	# D-069: Clear dialogue/confrontation dip — restore bus volumes to player slider settings.
-	# Safe to call even if confrontation beat already cleared the dip (no-op when empty).
-	AudioManager.clear_dip()
-
-	# D-061: unpause when dialogue closes
-	SimBridge.send_input({"action": InputMapper.Action.UNPAUSE, "timestamp_msec": Time.get_ticks_msec()})
-
-	if _active_tween and _active_tween.is_valid():
-		_active_tween.kill()
-	_active_tween = create_tween()
-	_active_tween.tween_property(panel, "modulate:a", 0.0, FADE_OUT)
-	_active_tween.tween_callback(func():
-		visible = false
-		_clear_options()
-		GameState.dialogue_active = false  # D-064: unblock movement after fade completes
-	)
-
-
-func is_dialogue_active() -> bool:
-	return _is_showing or GameState.dialogue_active
-
 
 func _on_option_pressed(index: int) -> void:
 	if index >= _option_controls.size():
@@ -191,46 +314,40 @@ func _on_option_pressed(index: int) -> void:
 	var text: String = _option_texts[index] if index < _option_texts.size() else ""
 	var is_confront: bool = _option_is_confrontation[index] if index < _option_is_confrontation.size() else false
 
+	# Append player's chosen response to the log
+	append_player_line(_npc_name, text)
+
 	if is_confront:
 		_start_confrontation_beat(rid, text)
 	else:
 		option_selected.emit(rid, text)
-		hide_dialogue()
+		_end_player_conversation()
 
 
-# D-063: Confrontation beat — delay before sending response.
-# 1. Dim dialogue to 70%, show monologue, dip audio
-# 2. Wait CONFRONTATION_BEAT_DURATION
-# 3. Emit option_selected, restore audio, hide dialogue
+# -- Confrontation beat (D-063) --
+
 func _start_confrontation_beat(response_id: String, text: String) -> void:
-	# Disable option clicks during beat
 	for ctrl in _option_controls:
 		if is_instance_valid(ctrl):
 			ctrl.mouse_filter = Control.MOUSE_FILTER_IGNORE
 
-	# Dim dialogue box
 	if _active_tween and _active_tween.is_valid():
 		_active_tween.kill()
 	_active_tween = create_tween()
 	_active_tween.tween_property(panel, "modulate:a", CONFRONTATION_DIM_ALPHA, 0.2)
 
-	# D-063: monologue beat — text from ui-strings.yaml (D-042)
 	confrontation_monologue.emit(UIStrings.get_text(CONFRONTATION_MONOLOGUE_KEY), CONFRONTATION_BEAT_DURATION)
-
-	# D-063: audio dip via AudioManager
 	AudioManager.apply_dip("confrontation")
 
-	# Delay, then complete
 	_beat_tween = create_tween()
 	_beat_tween.tween_interval(CONFRONTATION_BEAT_DURATION)
 	_beat_tween.tween_callback(func():
 		AudioManager.clear_dip()
 		option_selected.emit(response_id, text)
-		hide_dialogue()
+		_end_player_conversation()
 	)
 
 
-# Cancel an in-flight confrontation beat (e.g. player walks away mid-beat).
 func _cancel_beat() -> void:
 	if _beat_tween and _beat_tween.is_valid():
 		_beat_tween.kill()
@@ -238,6 +355,105 @@ func _cancel_beat() -> void:
 		AudioManager.clear_dip()
 
 
+# -- Log rendering --
+
+## Rebuild the dialogue log BBCode from all non-expired entries.
+func _rebuild_log() -> void:
+	if not dialogue_log:
+		return
+	var now := Time.get_ticks_msec()
+	var bbcode := ""
+	for entry in _log_entries:
+		var age_sec: float = (now - entry.timestamp_msec) / 1000.0
+		var alpha: float = 1.0
+		if age_sec > _entry_lifetime:
+			alpha = clampf(1.0 - (age_sec - _entry_lifetime) / _entry_fade, 0.0, 1.0)
+		if entry.is_passive:
+			alpha *= _passive_opacity
+		if alpha <= 0.0:
+			continue
+		var line := _format_entry(entry, alpha)
+		if not bbcode.is_empty():
+			bbcode += "\n"
+		bbcode += line
+	dialogue_log.text = bbcode
+
+
+## Format a single log entry as BBCode.
+func _format_entry(entry: Dictionary, alpha: float) -> String:
+	var speaker_color := _color_for_name(entry.speaker)
+	var target_color := _color_for_name(entry.target)
+
+	# Apply alpha to all colors in this line
+	var sc := _color_with_alpha(speaker_color, alpha)
+	var tc := _color_with_alpha(target_color, alpha)
+	var ac := _color_with_alpha(_arrow_color, alpha)
+	var txc := _color_with_alpha(_speech_color, alpha)
+
+	return "[color=%s][b]%s[/b][/color][color=%s] \u2192 [/color][color=%s][b]%s[/b][/color][color=%s]: %s[/color]" % [
+		sc, entry.speaker, ac, tc, entry.target, txc, entry.text
+	]
+
+
+## Get a stable color for a character name.
+func _color_for_name(char_name: String) -> Color:
+	if char_name == PLAYER_NAME:
+		return _player_color
+	if _npc_colors.is_empty():
+		return _speech_color
+	var idx := char_name.hash() % _npc_colors.size()
+	# hash() can return negative in GDScript — use abs
+	if idx < 0:
+		idx = -idx
+	return _npc_colors[idx]
+
+
+## Convert a Color to a hex string with alpha baked in.
+static func _color_with_alpha(base: Color, alpha: float) -> String:
+	return Color(base.r, base.g, base.b, base.a * alpha).to_html(true)
+
+
+# -- Entry expiry --
+
+## Remove fully expired entries. Hide panel if nothing remains.
+func _expire_entries() -> void:
+	if _log_entries.is_empty():
+		return
+	var now := Time.get_ticks_msec()
+	var total_lifetime_msec: int = int((_entry_lifetime + _entry_fade) * 1000.0)
+	var had_entries := _log_entries.size() > 0
+
+	# Remove expired entries from the front (oldest first)
+	while _log_entries.size() > 0:
+		var age: int = now - _log_entries[0].timestamp_msec
+		if age < total_lifetime_msec:
+			break
+		_log_entries.remove_at(0)
+
+	# Rebuild if entries were removed
+	if had_entries and _log_entries.size() == 0:
+		_rebuild_log()
+		if not _in_player_conversation:
+			hide_dialogue()
+	elif had_entries:
+		# Rebuild to update fading entries
+		_rebuild_log()
+
+
+# -- Visibility --
+
+## Ensure panel is visible (fade in if needed).
+func _ensure_visible() -> void:
+	if _is_showing:
+		return
+	visible = true
+	_is_showing = true
+	if _active_tween and _active_tween.is_valid():
+		_active_tween.kill()
+	_active_tween = create_tween()
+	_active_tween.tween_property(panel, "modulate:a", 1.0, FADE_IN)
+
+
 func _clear_options() -> void:
 	for ctrl in _option_controls:
 		if is_instance_valid(ctrl):
@@ -248,7 +464,7 @@ func _clear_options() -> void:
 	_option_is_confrontation.clear()
 
 
-# Hover callbacks — closures that capture the label reference.
+# Hover callbacks
 static func _make_hover_on(label: RichTextLabel) -> Callable:
 	return func():
 		label.add_theme_color_override("default_color", Constants.INSERT_COLOR_HOVER)

client/ui/dialogue_box.tscn

@@ -37,12 +37,14 @@ theme_override_constants/margin_bottom = 14
 layout_mode = 2
 theme_override_constants/separation = 10
 
-[node name="NpcSpeech" type="RichTextLabel" parent="PanelContainer/MarginContainer/VBoxContainer"]
+[node name="DialogueLog" type="RichTextLabel" parent="PanelContainer/MarginContainer/VBoxContainer"]
 layout_mode = 2
+size_flags_vertical = 3
 bbcode_enabled = true
 text = ""
-fit_content = true
-scroll_active = false
+fit_content = false
+scroll_active = true
+scroll_following = true
 
 [node name="OptionsContainer" type="VBoxContainer" parent="PanelContainer/MarginContainer/VBoxContainer"]
 layout_mode = 2