Week 32 packet
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# Week 32 — Richer-system production
## VGC-L156 — Finish the richer system’s data model
**Objective:** Make allowed states and values explicit.
**Time:** 55 minutes
### Instruction
Complete the chosen system’s validity rules. A save model needs field types, ranges, defaults and a version. An AI needs named states and transition conditions. A generator needs grid dimensions, allowed cell values and reserved spaces. Write these in a compact table next to the code. Reject or safely handle invalid data instead of silently inventing behavior. The table is a contract another beginner should be able to use to predict results.
### Worked example
A richer-system table can pair valid values with safe fallback behavior. Unknown checkpoint IDs map to a known start marker rather than a path loaded from input.
Scaffold C-STATE-SAVE — Validated inventory and checkpoint data
Setup: Attach to a Node named SaveData. This is a separate file from C-SAVE and only reads fixed known scalar fields. get_checkpoint_data returns plain data, not live node references. When applying a loaded checkpoint, the assignment maps checkpoint ID to a teacher-approved safe Marker2D, never to a filename supplied by the save.
```gdscript
extends Node
const PATH: String = "user://seed_station_v1.json"
func defaults() -> Dictionary:
return {"version": 1, "seed": 0, "water": 0, "checkpoint": "start"}
func _bounded_count(value: Variant) -> int:
if value is int or value is float:
return clampi(int(value), 0, 99)
return 0
func validate(raw: Variant) -> Dictionary:
var clean := defaults()
if not raw is Dictionary:
return clean
var data: Dictionary = raw
if data.get("version", 0) != 1:
return clean
clean["seed"] = _bounded_count(data.get("seed", 0))
clean["water"] = _bounded_count(data.get("water", 0))
var checkpoint: Variant = data.get("checkpoint", "start")
if checkpoint is String and checkpoint in ["start", "greenhouse"]:
clean["checkpoint"] = checkpoint
return clean
func save_data(raw: Dictionary) -> bool:
var file := FileAccess.open(PATH, FileAccess.WRITE)
if file == null:
return false
file.store_string(JSON.stringify(validate(raw)))
file.close()
return true
func load_data() -> Dictionary:
if not FileAccess.file_exists(PATH):
return defaults()
var file := FileAccess.open(PATH, FileAccess.READ)
if file == null:
return defaults()
var text: String = file.get_as_text()
file.close()
var parser := JSON.new()
if parser.parse(text) != OK:
return defaults()
return validate(parser.data)
```
Scaffold C-GUARD-AI — A readable patrol/chase/return state machine
Setup: Create CharacterBody2D Guard with visible circle or polygon and matching collider. Layer 4 mask 2 for walls. Attach script and assign target to your Player instance in Inspector. Level is one open rectangle; this is steering, not navigation around walls. Damage remains a separate sensor/manager event. Draw detection radii on a design diagram before tuning values.
```gdscript
extends CharacterBody2D
enum Mode { PATROL, CHASE, RETURN }
@export var target: Node2D
@export var speed: float = 70.0
var mode: Mode = Mode.PATROL
var home: Vector2
var patrol_target: Vector2
func _ready() -> void:
home = global_position
patrol_target = home + Vector2(80, 0)
func _physics_process(delta: float) -> void:
if not is_instance_valid(target):
velocity = Vector2.ZERO
return
var distance: float = global_position.distance_to(target.global_position)
if mode != Mode.CHASE and distance < 120.0:
mode = Mode.CHASE
elif mode == Mode.CHASE and distance > 180.0:
mode = Mode.RETURN
var destination: Vector2
if mode == Mode.CHASE:
destination = target.global_position
elif mode == Mode.RETURN:
destination = home
if global_position.distance_to(home) <= maxf(3.0, speed * delta):
mode = Mode.PATROL
else:
destination = patrol_target
if global_position.distance_to(patrol_target) <= maxf(3.0, speed * delta):
patrol_target = home if patrol_target != home else home + Vector2(80, 0)
var offset := destination - global_position
velocity = offset.normalized() * minf(speed, offset.length() / maxf(delta, 0.001))
move_and_slide()
```
Scaffold C-GRID — A deterministic grid with a guaranteed clear route
Setup: Attach to Node2D GridLab. This example draws, not physics, so the assignment adds matching wall collision only after validation. Grid is 8 columns by 6 rows at 40 pixels per cell. Row 0 and column 7 are a guaranteed clear route from (0,0) to (7,5). RNG seed is a nonpersonal integer.
```gdscript
extends Node2D
const COLS: int = 8
const ROWS: int = 6
const CELL: int = 40
var cells: Array = []
func _ready() -> void:
var rng := RandomNumberGenerator.new()
rng.seed = 2468
for y in range(ROWS):
var row: Array[int] = []
for x in range(COLS):
var blocked: bool = y != 0 and x != COLS - 1 and rng.randf() < 0.25
row.append(1 if blocked else 0)
cells.append(row)
queue_redraw()
func _draw() -> void:
for y in range(cells.size()):
for x in range(cells[y].size()):
var color := Color.DIM_GRAY if cells[y][x] == 1 else Color.BEIGE
draw_rect(Rect2(x * CELL, y * CELL, CELL - 2, CELL - 2), color)
```
### Assignment
1. Finalize the richer-system validity table.
2. Add tests for two invalid or boundary cases not already covered.
### Acceptance checks
- The table matches code.
- Invalid inputs follow a documented safe behavior.
**Submit:** Richer-system data/model checkpoint and new tests.
**Question:** Why are defaults part of a save schema rather than an afterthought?
**Support:** Use the focused test scene from week 30 to compare isolated behavior with the main game. Keep one explicit state owner. Start with the first assigned task and re-run its acceptance test before adding the remaining feature.
**Optional extension:** Add one validated field, AI cue or generation constraint only after existing tests pass. Document one changed parameter, your prediction, and the observed effect; optional, not required for completion.
**Optional free reading:** [Your first 2D game](https://docs.godotengine.org/en/stable/getting_started/first_2d_game/index.html)
---
## VGC-L157 — Finish ordinary richer-system behavior
**Objective:** Connect a complete useful feature to play.
**Time:** 55 minutes
### Instruction
Make the richer system fully useful within the game’s scope. For saves, demonstrate a meaningful stop/relaunch restoration without duplication. For AI, show patrol, detection, chase, escape and return with readable cues. For generation, rebuild a playable room from a named seed with matching walls and a guaranteed route. Test a normal full sequence, not just one function. Keep limitations explicit: direct steering is not maze pathfinding, and one guaranteed route is not full-map connectivity.
### Worked example
A richer-system table can pair valid values with safe fallback behavior. Unknown checkpoint IDs map to a known start marker rather than a path loaded from input.
Scaffold C-STATE-SAVE — Validated inventory and checkpoint data
Setup: Attach to a Node named SaveData. This is a separate file from C-SAVE and only reads fixed known scalar fields. get_checkpoint_data returns plain data, not live node references. When applying a loaded checkpoint, the assignment maps checkpoint ID to a teacher-approved safe Marker2D, never to a filename supplied by the save.
```gdscript
extends Node
const PATH: String = "user://seed_station_v1.json"
func defaults() -> Dictionary:
return {"version": 1, "seed": 0, "water": 0, "checkpoint": "start"}
func _bounded_count(value: Variant) -> int:
if value is int or value is float:
return clampi(int(value), 0, 99)
return 0
func validate(raw: Variant) -> Dictionary:
var clean := defaults()
if not raw is Dictionary:
return clean
var data: Dictionary = raw
if data.get("version", 0) != 1:
return clean
clean["seed"] = _bounded_count(data.get("seed", 0))
clean["water"] = _bounded_count(data.get("water", 0))
var checkpoint: Variant = data.get("checkpoint", "start")
if checkpoint is String and checkpoint in ["start", "greenhouse"]:
clean["checkpoint"] = checkpoint
return clean
func save_data(raw: Dictionary) -> bool:
var file := FileAccess.open(PATH, FileAccess.WRITE)
if file == null:
return false
file.store_string(JSON.stringify(validate(raw)))
file.close()
return true
func load_data() -> Dictionary:
if not FileAccess.file_exists(PATH):
return defaults()
var file := FileAccess.open(PATH, FileAccess.READ)
if file == null:
return defaults()
var text: String = file.get_as_text()
file.close()
var parser := JSON.new()
if parser.parse(text) != OK:
return defaults()
return validate(parser.data)
```
Scaffold C-GUARD-AI — A readable patrol/chase/return state machine
Setup: Create CharacterBody2D Guard with visible circle or polygon and matching collider. Layer 4 mask 2 for walls. Attach script and assign target to your Player instance in Inspector. Level is one open rectangle; this is steering, not navigation around walls. Damage remains a separate sensor/manager event. Draw detection radii on a design diagram before tuning values.
```gdscript
extends CharacterBody2D
enum Mode { PATROL, CHASE, RETURN }
@export var target: Node2D
@export var speed: float = 70.0
var mode: Mode = Mode.PATROL
var home: Vector2
var patrol_target: Vector2
func _ready() -> void:
home = global_position
patrol_target = home + Vector2(80, 0)
func _physics_process(delta: float) -> void:
if not is_instance_valid(target):
velocity = Vector2.ZERO
return
var distance: float = global_position.distance_to(target.global_position)
if mode != Mode.CHASE and distance < 120.0:
mode = Mode.CHASE
elif mode == Mode.CHASE and distance > 180.0:
mode = Mode.RETURN
var destination: Vector2
if mode == Mode.CHASE:
destination = target.global_position
elif mode == Mode.RETURN:
destination = home
if global_position.distance_to(home) <= maxf(3.0, speed * delta):
mode = Mode.PATROL
else:
destination = patrol_target
if global_position.distance_to(patrol_target) <= maxf(3.0, speed * delta):
patrol_target = home if patrol_target != home else home + Vector2(80, 0)
var offset := destination - global_position
velocity = offset.normalized() * minf(speed, offset.length() / maxf(delta, 0.001))
move_and_slide()
```
Scaffold C-GRID — A deterministic grid with a guaranteed clear route
Setup: Attach to Node2D GridLab. This example draws, not physics, so the assignment adds matching wall collision only after validation. Grid is 8 columns by 6 rows at 40 pixels per cell. Row 0 and column 7 are a guaranteed clear route from (0,0) to (7,5). RNG seed is a nonpersonal integer.
```gdscript
extends Node2D
const COLS: int = 8
const ROWS: int = 6
const CELL: int = 40
var cells: Array = []
func _ready() -> void:
var rng := RandomNumberGenerator.new()
rng.seed = 2468
for y in range(ROWS):
var row: Array[int] = []
for x in range(COLS):
var blocked: bool = y != 0 and x != COLS - 1 and rng.randf() < 0.25
row.append(1 if blocked else 0)
cells.append(row)
queue_redraw()
func _draw() -> void:
for y in range(cells.size()):
for x in range(cells[y].size()):
var color := Color.DIM_GRAY if cells[y][x] == 1 else Color.BEIGE
draw_rect(Rect2(x * CELL, y * CELL, CELL - 2, CELL - 2), color)
```
### Assignment
1. Complete and test one full ordinary sequence for the chosen system.
2. Write the exact reproduction steps.
### Acceptance checks
- The sequence works through the main game, not only a lab.
- The feature’s claimed scope matches evidence.
**Submit:** Richer-system ordinary-path source and reproduction log.
**Question:** Why must the system be tested through the main game?
**Support:** Use the focused test scene from week 30 to compare isolated behavior with the main game. Keep one explicit state owner. Start with the first assigned task and re-run its acceptance test before adding the remaining feature.
**Optional extension:** Add one validated field, AI cue or generation constraint only after existing tests pass. Document one changed parameter, your prediction, and the observed effect; optional, not required for completion.
**Optional free reading:** [Your first 2D game](https://docs.godotengine.org/en/stable/getting_started/first_2d_game/index.html)
---
## VGC-L158 — Harden failure and boundary paths
**Objective:** Prevent advanced-system errors from corrupting the game.
**Time:** 55 minutes
### Instruction
Test the richer system against adversarial conditions. Saves need malformed and unsupported-version data; AI needs missing target and threshold-band tests; generation needs repeated regeneration and reserved-cell checks. Choose at least four cases appropriate to the system and predict results first. A safe fallback should preserve a playable state and communicate what happened. Do not load arbitrary scripts, paths or external services as a shortcut to recovery.
### Worked example
A richer-system table can pair valid values with safe fallback behavior. Unknown checkpoint IDs map to a known start marker rather than a path loaded from input.
Scaffold C-STATE-SAVE — Validated inventory and checkpoint data
Setup: Attach to a Node named SaveData. This is a separate file from C-SAVE and only reads fixed known scalar fields. get_checkpoint_data returns plain data, not live node references. When applying a loaded checkpoint, the assignment maps checkpoint ID to a teacher-approved safe Marker2D, never to a filename supplied by the save.
```gdscript
extends Node
const PATH: String = "user://seed_station_v1.json"
func defaults() -> Dictionary:
return {"version": 1, "seed": 0, "water": 0, "checkpoint": "start"}
func _bounded_count(value: Variant) -> int:
if value is int or value is float:
return clampi(int(value), 0, 99)
return 0
func validate(raw: Variant) -> Dictionary:
var clean := defaults()
if not raw is Dictionary:
return clean
var data: Dictionary = raw
if data.get("version", 0) != 1:
return clean
clean["seed"] = _bounded_count(data.get("seed", 0))
clean["water"] = _bounded_count(data.get("water", 0))
var checkpoint: Variant = data.get("checkpoint", "start")
if checkpoint is String and checkpoint in ["start", "greenhouse"]:
clean["checkpoint"] = checkpoint
return clean
func save_data(raw: Dictionary) -> bool:
var file := FileAccess.open(PATH, FileAccess.WRITE)
if file == null:
return false
file.store_string(JSON.stringify(validate(raw)))
file.close()
return true
func load_data() -> Dictionary:
if not FileAccess.file_exists(PATH):
return defaults()
var file := FileAccess.open(PATH, FileAccess.READ)
if file == null:
return defaults()
var text: String = file.get_as_text()
file.close()
var parser := JSON.new()
if parser.parse(text) != OK:
return defaults()
return validate(parser.data)
```
Scaffold C-GUARD-AI — A readable patrol/chase/return state machine
Setup: Create CharacterBody2D Guard with visible circle or polygon and matching collider. Layer 4 mask 2 for walls. Attach script and assign target to your Player instance in Inspector. Level is one open rectangle; this is steering, not navigation around walls. Damage remains a separate sensor/manager event. Draw detection radii on a design diagram before tuning values.
```gdscript
extends CharacterBody2D
enum Mode { PATROL, CHASE, RETURN }
@export var target: Node2D
@export var speed: float = 70.0
var mode: Mode = Mode.PATROL
var home: Vector2
var patrol_target: Vector2
func _ready() -> void:
home = global_position
patrol_target = home + Vector2(80, 0)
func _physics_process(delta: float) -> void:
if not is_instance_valid(target):
velocity = Vector2.ZERO
return
var distance: float = global_position.distance_to(target.global_position)
if mode != Mode.CHASE and distance < 120.0:
mode = Mode.CHASE
elif mode == Mode.CHASE and distance > 180.0:
mode = Mode.RETURN
var destination: Vector2
if mode == Mode.CHASE:
destination = target.global_position
elif mode == Mode.RETURN:
destination = home
if global_position.distance_to(home) <= maxf(3.0, speed * delta):
mode = Mode.PATROL
else:
destination = patrol_target
if global_position.distance_to(patrol_target) <= maxf(3.0, speed * delta):
patrol_target = home if patrol_target != home else home + Vector2(80, 0)
var offset := destination - global_position
velocity = offset.normalized() * minf(speed, offset.length() / maxf(delta, 0.001))
move_and_slide()
```
Scaffold C-GRID — A deterministic grid with a guaranteed clear route
Setup: Attach to Node2D GridLab. This example draws, not physics, so the assignment adds matching wall collision only after validation. Grid is 8 columns by 6 rows at 40 pixels per cell. Row 0 and column 7 are a guaranteed clear route from (0,0) to (7,5). RNG seed is a nonpersonal integer.
```gdscript
extends Node2D
const COLS: int = 8
const ROWS: int = 6
const CELL: int = 40
var cells: Array = []
func _ready() -> void:
var rng := RandomNumberGenerator.new()
rng.seed = 2468
for y in range(ROWS):
var row: Array[int] = []
for x in range(COLS):
var blocked: bool = y != 0 and x != COLS - 1 and rng.randf() < 0.25
row.append(1 if blocked else 0)
cells.append(row)
queue_redraw()
func _draw() -> void:
for y in range(cells.size()):
for x in range(cells[y].size()):
var color := Color.DIM_GRAY if cells[y][x] == 1 else Color.BEIGE
draw_rect(Rect2(x * CELL, y * CELL, CELL - 2, CELL - 2), color)
```
### Assignment
1. Run four richer-system adversarial cases with predictions.
2. Repair the most important discrepancy and retest.
### Acceptance checks
- No tested case crashes or executes untrusted content.
- Fallback leaves a valid, explained state.
**Submit:** Robustness matrix and repaired checkpoint.
**Question:** Why is a silent fallback sometimes misleading?
**Support:** Use the focused test scene from week 30 to compare isolated behavior with the main game. Keep one explicit state owner. Start with the first assigned task and re-run its acceptance test before adding the remaining feature.
**Optional extension:** Add one validated field, AI cue or generation constraint only after existing tests pass. Document one changed parameter, your prediction, and the observed effect; optional, not required for completion.
**Optional free reading:** [Your first 2D game](https://docs.godotengine.org/en/stable/getting_started/first_2d_game/index.html)
---
## VGC-L159 — Reconcile restart and persistence policies
**Objective:** Prevent state leaks across repeated play sessions.
**Time:** 55 minutes
### Instruction
The richer system must agree with Restart and New Game. A loaded inventory cannot coexist with respawned rewards unless the policy accounts for them. A restarted AI needs a valid home and target. Regenerated rooms must remove old colliders. Write a reset matrix for transient state, persistent progress and comfort settings. Run two consecutive rounds or loads and compare expected values. Clearing everything blindly can erase intended preferences; preserving everything can leak ended state.
### Worked example
A richer-system table can pair valid values with safe fallback behavior. Unknown checkpoint IDs map to a known start marker rather than a path loaded from input.
Scaffold C-STATE-SAVE — Validated inventory and checkpoint data
Setup: Attach to a Node named SaveData. This is a separate file from C-SAVE and only reads fixed known scalar fields. get_checkpoint_data returns plain data, not live node references. When applying a loaded checkpoint, the assignment maps checkpoint ID to a teacher-approved safe Marker2D, never to a filename supplied by the save.
```gdscript
extends Node
const PATH: String = "user://seed_station_v1.json"
func defaults() -> Dictionary:
return {"version": 1, "seed": 0, "water": 0, "checkpoint": "start"}
func _bounded_count(value: Variant) -> int:
if value is int or value is float:
return clampi(int(value), 0, 99)
return 0
func validate(raw: Variant) -> Dictionary:
var clean := defaults()
if not raw is Dictionary:
return clean
var data: Dictionary = raw
if data.get("version", 0) != 1:
return clean
clean["seed"] = _bounded_count(data.get("seed", 0))
clean["water"] = _bounded_count(data.get("water", 0))
var checkpoint: Variant = data.get("checkpoint", "start")
if checkpoint is String and checkpoint in ["start", "greenhouse"]:
clean["checkpoint"] = checkpoint
return clean
func save_data(raw: Dictionary) -> bool:
var file := FileAccess.open(PATH, FileAccess.WRITE)
if file == null:
return false
file.store_string(JSON.stringify(validate(raw)))
file.close()
return true
func load_data() -> Dictionary:
if not FileAccess.file_exists(PATH):
return defaults()
var file := FileAccess.open(PATH, FileAccess.READ)
if file == null:
return defaults()
var text: String = file.get_as_text()
file.close()
var parser := JSON.new()
if parser.parse(text) != OK:
return defaults()
return validate(parser.data)
```
Scaffold C-GRID — A deterministic grid with a guaranteed clear route
Setup: Attach to Node2D GridLab. This example draws, not physics, so the assignment adds matching wall collision only after validation. Grid is 8 columns by 6 rows at 40 pixels per cell. Row 0 and column 7 are a guaranteed clear route from (0,0) to (7,5). RNG seed is a nonpersonal integer.
```gdscript
extends Node2D
const COLS: int = 8
const ROWS: int = 6
const CELL: int = 40
var cells: Array = []
func _ready() -> void:
var rng := RandomNumberGenerator.new()
rng.seed = 2468
for y in range(ROWS):
var row: Array[int] = []
for x in range(COLS):
var blocked: bool = y != 0 and x != COLS - 1 and rng.randf() < 0.25
row.append(1 if blocked else 0)
cells.append(row)
queue_redraw()
func _draw() -> void:
for y in range(cells.size()):
for x in range(cells[y].size()):
var color := Color.DIM_GRAY if cells[y][x] == 1 else Color.BEIGE
draw_rect(Rect2(x * CELL, y * CELL, CELL - 2, CELL - 2), color)
```
Scaffold C-STATES — Explicit game states and gated scoring
Setup: Attach to Node root StateLab with child Label Status. This is a standalone demonstrator; call start_round, add_points, finish_round from buttons or Remote Inspector. In a real game the manager owns this state. Additional Player and spawner scripts must also honor the manager’s state, or be disabled when finishing.
```gdscript
extends Node
enum Phase { TITLE, PLAY, WIN, LOSE }
var phase: Phase = Phase.TITLE
var score: int = 0
func _ready() -> void:
_show()
func start_round() -> void:
score = 0
phase = Phase.PLAY
_show()
func add_points(amount: int) -> void:
if phase != Phase.PLAY:
return
score += maxi(amount, 0)
_show()
func finish_round(won: bool) -> void:
if phase != Phase.PLAY:
return
phase = Phase.WIN if won else Phase.LOSE
_show()
func _show() -> void:
$Status.text = "State: %s | Score: %d" % [Phase.keys()[phase], score]
```
### Assignment
1. Write the reset/persistence matrix.
2. Test two consecutive restarts, loads or regenerations as appropriate.
### Acceptance checks
- State follows the matrix after both cycles.
- No duplicated object, reward or stale target remains.
**Submit:** Reset-policy matrix and two-cycle integration log.
**Question:** Why separate transient state from persistent progress?
**Support:** Use the focused test scene from week 30 to compare isolated behavior with the main game. Keep one explicit state owner. Start with the first assigned task and re-run its acceptance test before adding the remaining feature.
**Optional extension:** Add one validated field, AI cue or generation constraint only after existing tests pass. Document one changed parameter, your prediction, and the observed effect; optional, not required for completion.
**Optional free reading:** [Your first 2D game](https://docs.godotengine.org/en/stable/getting_started/first_2d_game/index.html)
---
## VGC-L160 — Complete a content-ready integrated build
**Objective:** Create a stable candidate before expanding level or story content.
**Time:** 55 minutes
### Instruction
Run the complete twelve-test contract against the integrated game. Any remaining minimum defect becomes a blocking task. If tests pass, name the build content-ready and save a restore-tested snapshot. This is the base for adding the promised amount of content, not a reason to add unrelated features. Update architecture diagrams if actual code has changed. A technical design document is useful only when it reflects the artifact being assessed.
### Worked example
A richer-system table can pair valid values with safe fallback behavior. Unknown checkpoint IDs map to a known start marker rather than a path loaded from input.
Scaffold C-TESTS — A tiny pure-function test harness
Setup: Attach to Node TestLab. If using command line, create a separate SceneTree harness rather than running this Node script with --script. Run current TestLab scene in editor; assert reports a failed condition in Debugger. No external test framework or package is needed.
```gdscript
extends Node
func bounded_score(old_score: int, change: int) -> int:
return clampi(old_score + change, 0, 999)
func _ready() -> void:
assert(bounded_score(10, 2) == 12)
assert(bounded_score(0, -3) == 0)
assert(bounded_score(998, 9) == 999)
print("3 score checks passed")
```
### Assignment
1. Run all twelve acceptance tests.
2. Package a content-ready checkpoint and update diagrams to match code.
### Acceptance checks
- Every minimum test has current evidence or a clearly blocking issue.
- Documentation names actual functions and nodes.
**Submit:** Content-ready source artifact, twelve-test report and updated technical design.
**Question:** Why update diagrams after implementation changes?
**Support:** Use the focused test scene from week 30 to compare isolated behavior with the main game. Keep one explicit state owner. Start with the first assigned task and re-run its acceptance test before adding the remaining feature.
**Optional extension:** Add one validated field, AI cue or generation constraint only after existing tests pass. Document one changed parameter, your prediction, and the observed effect; optional, not required for completion.
**Optional free reading:** [Your first 2D game](https://docs.godotengine.org/en/stable/getting_started/first_2d_game/index.html)
---