Implement crouch and prone stances

AGRARIAN_DEVELOPMENT_ROADMAP.md

@@ -375,7 +375,7 @@ Target deliverable: A small group can join a server, spawn into one biome, gathe
 - [x] Define real-world baseline walking speed. Decision: baseline adult walking speed is `1.4 m/s` (`140 Unreal units/s`), with MVP tuning allowance up to about `1.6 m/s` for brisk walking. Movement speed does not scale with the `4 real hours = 1 in-game day` calendar.
 - [x] Define real-world baseline running speed. Decision: sustainable adult running target is `3.0 m/s` (`300 Unreal units/s`); MVP sprint is a short burst at `5.5 m/s` (`550 Unreal units/s`) with stamina limits. Movement speed does not scale with the calendar.
 - [x] Connect movement speed to age, condition, strength, endurance, hunger, thirst, injury, carried weight, and terrain. Implemented with live survival/inventory modifiers plus replicated age, condition, strength, endurance, and terrain hooks.
-- [ ] Implement crouching if needed.
+- [x] Implement crouching and prone movement stances. Decision: `C` toggles crouch at `55%` movement speed and `Z` toggles prone at `25%` movement speed. Gamepad mappings are Right Shoulder for crouch and Left Shoulder for prone. Sprint is disabled while crouched or prone.
 - [x] Implement jumping if needed.
 - [x] Implement interaction trace.
 - [ ] Implement interact prompt.
@@ -1465,4 +1465,4 @@ Earliest incomplete foundation items:
 
 Immediate next item:
 
-- [ ] Implement crouching if needed.
+- [ ] Implement interact prompt.

Docs/MovementAndTimeScaleBaseline.md

@@ -116,6 +116,26 @@ Later movement work should separate:
 - injury/load/terrain modifiers;
 - skill, age, care history, and condition effects.
 
+## MVP Stance Movement
+
+The first stance pass supports crouch and prone as low-movement modes that keep
+the same real-distance philosophy as walking and sprinting.
+
+Current defaults:
+
+- crouch toggles with `C` or gamepad Right Shoulder;
+- prone toggles with `Z` or gamepad Left Shoulder;
+- crouch uses `55%` of the current movement speed;
+- prone uses `25%` of the current movement speed;
+- sprint cannot start while crouched or prone;
+- entering prone exits crouch so the player has one active low stance at a
+  time.
+
+The MVP prone state is replicated and affects movement speed. Dedicated prone
+animation, capsule resizing, crawl-specific collision, stealth/noise, and
+surface-specific crawl penalties are reserved for later animation and traversal
+passes.
+
 ## Movement Modifier Implementation
 
 MVP movement speed is now calculated as:

Scripts/setup_stance_input.py

@@ -0,0 +1,101 @@
+import unreal
+
+
+STANCE_DEFAULTS = {
+    "CrouchSpeedMultiplier": 0.55,
+    "ProneSpeedMultiplier": 0.25,
+}
+
+
+def load(path):
+    asset = unreal.EditorAssetLibrary.load_asset(path)
+    if not asset:
+        raise RuntimeError(f"Could not load {path}")
+    return asset
+
+
+def create_input_action(path):
+    existing = unreal.EditorAssetLibrary.load_asset(path)
+    if existing:
+        return existing
+
+    template_path = "/Game/Input/Actions/IA_Interact"
+    template = unreal.EditorAssetLibrary.load_asset(template_path)
+    if not template:
+        template_path = "/Game/Input/Actions/IA_Jump"
+        template = unreal.EditorAssetLibrary.load_asset(template_path)
+    if not template:
+        raise RuntimeError("Could not load an input action template")
+
+    action = unreal.EditorAssetLibrary.duplicate_asset(template_path, path)
+    if not action:
+        raise RuntimeError(f"Could not create {path}")
+    return action
+
+
+def set_boolean_value_type(action):
+    action.set_editor_property("value_type", unreal.InputActionValueType.BOOLEAN)
+    try:
+        action.set_editor_property("triggers", [])
+    except Exception as exc:
+        unreal.log_warning(f"Could not clear stance triggers; keeping template defaults: {exc}")
+    unreal.EditorAssetLibrary.save_loaded_asset(action)
+
+
+def mapping_exists(context, action, key_name):
+    mapping_data = context.get_editor_property("default_key_mappings")
+    for mapping in list(mapping_data.get_editor_property("mappings")):
+        mapping_key = mapping.get_editor_property("key")
+        if (
+            mapping.get_editor_property("action") == action
+            and str(mapping_key.get_editor_property("key_name")) == key_name
+        ):
+            return True
+    return False
+
+
+def map_key(context, action, key_name):
+    if mapping_exists(context, action, key_name):
+        unreal.log(f"Mapping already exists: {action.get_name()} -> {key_name}")
+        return
+
+    key = unreal.Key()
+    key.set_editor_property("key_name", key_name)
+
+    mapping_data = context.get_editor_property("default_key_mappings")
+    mappings = list(mapping_data.get_editor_property("mappings"))
+    new_mapping = unreal.EnhancedActionKeyMapping()
+    new_mapping.set_editor_property("action", action)
+    new_mapping.set_editor_property("key", key)
+    mappings.append(new_mapping)
+    mapping_data.set_editor_property("mappings", mappings)
+    context.set_editor_property("default_key_mappings", mapping_data)
+
+    unreal.log(f"Added mapping: {action.get_name()} -> {key_name}")
+
+
+def main():
+    crouch_action = create_input_action("/Game/Input/Actions/IA_Crouch")
+    prone_action = create_input_action("/Game/Input/Actions/IA_Prone")
+    set_boolean_value_type(crouch_action)
+    set_boolean_value_type(prone_action)
+
+    context = load("/Game/Input/IMC_Default")
+    map_key(context, crouch_action, "C")
+    map_key(context, crouch_action, "Gamepad_RightShoulder")
+    map_key(context, prone_action, "Z")
+    map_key(context, prone_action, "Gamepad_LeftShoulder")
+    unreal.EditorAssetLibrary.save_loaded_asset(context)
+
+    character_bp = load("/Game/ThirdPerson/Blueprints/BP_ThirdPersonCharacter")
+    character_cdo = unreal.get_default_object(character_bp.generated_class())
+    character_cdo.set_editor_property("CrouchAction", crouch_action)
+    character_cdo.set_editor_property("ProneAction", prone_action)
+    for property_name, value in STANCE_DEFAULTS.items():
+        character_cdo.set_editor_property(property_name, value)
+    unreal.EditorAssetLibrary.save_loaded_asset(character_bp)
+
+    unreal.log("Agrarian stance input setup complete.")
+
+
+main()

Scripts/verify_stance_input.py

@@ -0,0 +1,63 @@
+import math
+import unreal
+
+
+STANCE_DEFAULTS = {
+    "CrouchSpeedMultiplier": 0.55,
+    "ProneSpeedMultiplier": 0.25,
+}
+
+
+def load(path):
+    asset = unreal.EditorAssetLibrary.load_asset(path)
+    if not asset:
+        raise RuntimeError(f"Could not load {path}")
+    return asset
+
+
+def mapping_found(context, action, key_name):
+    mapping_data = context.get_editor_property("default_key_mappings")
+    for mapping in list(mapping_data.get_editor_property("mappings")):
+        mapping_key = mapping.get_editor_property("key")
+        if (
+            mapping.get_editor_property("action") == action
+            and str(mapping_key.get_editor_property("key_name")) == key_name
+        ):
+            return True
+    return False
+
+
+def main():
+    crouch_action = load("/Game/Input/Actions/IA_Crouch")
+    prone_action = load("/Game/Input/Actions/IA_Prone")
+    context = load("/Game/Input/IMC_Default")
+    character_bp = load("/Game/ThirdPerson/Blueprints/BP_ThirdPersonCharacter")
+    character_cdo = unreal.get_default_object(character_bp.generated_class())
+
+    missing = []
+    for action, key_name in [
+        (crouch_action, "C"),
+        (crouch_action, "Gamepad_RightShoulder"),
+        (prone_action, "Z"),
+        (prone_action, "Gamepad_LeftShoulder"),
+    ]:
+        if not mapping_found(context, action, key_name):
+            missing.append(f"missing mapping {action.get_name()} -> {key_name}")
+
+    if character_cdo.get_editor_property("CrouchAction") != crouch_action:
+        missing.append("BP_ThirdPersonCharacter CrouchAction is not IA_Crouch")
+    if character_cdo.get_editor_property("ProneAction") != prone_action:
+        missing.append("BP_ThirdPersonCharacter ProneAction is not IA_Prone")
+
+    for property_name, expected in STANCE_DEFAULTS.items():
+        actual = float(character_cdo.get_editor_property(property_name))
+        if not math.isclose(actual, expected, rel_tol=0.0, abs_tol=0.01):
+            missing.append(f"{property_name}: expected {expected}, got {actual}")
+
+    if missing:
+        raise RuntimeError("Stance input verification failed: " + "; ".join(missing))
+
+    unreal.log("Agrarian stance input verification complete.")
+
+
+main()

Source/AgrarianGame/AgrarianGameCharacter.cpp

@@ -31,6 +31,7 @@ AAgrarianGameCharacter::AAgrarianGameCharacter()
 	bUseControllerRotationRoll = false;
 
 	// Configure character movement
+	GetCharacterMovement()->NavAgentProps.bCanCrouch = true;
 	GetCharacterMovement()->bOrientRotationToMovement = true;
 	GetCharacterMovement()->RotationRate = FRotator(0.0f, 500.0f, 0.0f);
 
@@ -39,6 +40,7 @@ AAgrarianGameCharacter::AAgrarianGameCharacter()
 	GetCharacterMovement()->JumpZVelocity = 500.f;
 	GetCharacterMovement()->AirControl = 0.35f;
 	GetCharacterMovement()->MaxWalkSpeed = WalkSpeed;
+	GetCharacterMovement()->MaxWalkSpeedCrouched = WalkSpeed * CrouchSpeedMultiplier;
 	GetCharacterMovement()->MinAnalogWalkSpeed = 20.f;
 	GetCharacterMovement()->BrakingDecelerationWalking = 2000.f;
 	GetCharacterMovement()->BrakingDecelerationFalling = 1500.0f;
@@ -95,6 +97,7 @@ void AAgrarianGameCharacter::GetLifetimeReplicatedProps(TArray<FLifetimeProperty
 {
 	Super::GetLifetimeReplicatedProps(OutLifetimeProps);
 	DOREPLIFETIME(AAgrarianGameCharacter, bWantsToSprint);
+	DOREPLIFETIME(AAgrarianGameCharacter, bIsProne);
 	DOREPLIFETIME(AAgrarianGameCharacter, AgeYears);
 	DOREPLIFETIME(AAgrarianGameCharacter, PhysicalConditionMultiplier);
 	DOREPLIFETIME(AAgrarianGameCharacter, StrengthMultiplier);
@@ -130,6 +133,16 @@ void AAgrarianGameCharacter::SetupPlayerInputComponent(UInputComponent* PlayerIn
 			EnhancedInputComponent->BindAction(SprintAction, ETriggerEvent::Canceled, this, &AAgrarianGameCharacter::StopSprint);
 		}
 
+		if (CrouchAction)
+		{
+			EnhancedInputComponent->BindAction(CrouchAction, ETriggerEvent::Started, this, &AAgrarianGameCharacter::ToggleCrouchStance);
+		}
+
+		if (ProneAction)
+		{
+			EnhancedInputComponent->BindAction(ProneAction, ETriggerEvent::Started, this, &AAgrarianGameCharacter::ToggleProneStance);
+		}
+
 		if (ToggleCameraAction)
 		{
 			EnhancedInputComponent->BindAction(ToggleCameraAction, ETriggerEvent::Started, this, &AAgrarianGameCharacter::ToggleCameraPerspective);
@@ -166,6 +179,11 @@ void AAgrarianGameCharacter::Interact()
 
 void AAgrarianGameCharacter::StartSprint()
 {
+	if (bIsProne || bIsCrouched)
+	{
+		return;
+	}
+
 	SetWantsToSprint(true);
 }
 
@@ -174,6 +192,32 @@ void AAgrarianGameCharacter::StopSprint()
 	SetWantsToSprint(false);
 }
 
+void AAgrarianGameCharacter::ToggleCrouchStance()
+{
+	if (bIsProne)
+	{
+		SetProne(false);
+		return;
+	}
+
+	SetWantsToSprint(false);
+	if (bIsCrouched)
+	{
+		UnCrouch();
+	}
+	else
+	{
+		Crouch();
+	}
+
+	ApplyMovementSpeed();
+}
+
+void AAgrarianGameCharacter::ToggleProneStance()
+{
+	SetProne(!bIsProne);
+}
+
 void AAgrarianGameCharacter::ToggleCameraPerspective()
 {
 	SetFirstPersonCamera(!bFirstPersonCamera);
@@ -235,6 +279,8 @@ bool AAgrarianGameCharacter::CanSprint() const
 {
 	return SurvivalComponent
 		&& SurvivalComponent->IsAlive()
+		&& !bIsProne
+		&& !bIsCrouched
 		&& SurvivalComponent->Survival.Stamina > MinSprintStamina;
 }
 
@@ -253,6 +299,29 @@ float AAgrarianGameCharacter::GetCurrentMovementSpeedMultiplier() const
 	return CalculateMovementSpeedMultiplier();
 }
 
+void AAgrarianGameCharacter::SetProne(bool bNewProne)
+{
+	if (bIsProne == bNewProne)
+	{
+		return;
+	}
+
+	bIsProne = bNewProne;
+
+	if (bIsProne)
+	{
+		SetWantsToSprint(false);
+		UnCrouch();
+	}
+
+	ApplyMovementSpeed();
+
+	if (!HasAuthority())
+	{
+		ServerSetProne(bIsProne);
+	}
+}
+
 void AAgrarianGameCharacter::SetTerrainMovementMultiplier(float NewTerrainMovementMultiplier)
 {
 	TerrainMovementMultiplier = FMath::Clamp(NewTerrainMovementMultiplier, 0.25f, 1.25f);
@@ -264,7 +333,9 @@ void AAgrarianGameCharacter::ApplyMovementSpeed()
 	if (UCharacterMovementComponent* MovementComponent = GetCharacterMovement())
 	{
 		const float BaseSpeed = IsSprinting() ? SprintSpeed : WalkSpeed;
-		MovementComponent->MaxWalkSpeed = FMath::Max(0.0f, BaseSpeed * CalculateMovementSpeedMultiplier());
+		const float FinalSpeed = FMath::Max(0.0f, BaseSpeed * CalculateMovementSpeedMultiplier());
+		MovementComponent->MaxWalkSpeed = FinalSpeed;
+		MovementComponent->MaxWalkSpeedCrouched = FinalSpeed;
 	}
 }
 
@@ -278,6 +349,7 @@ float AAgrarianGameCharacter::CalculateMovementSpeedMultiplier() const
 		* TraitMultiplier
 		* CalculateSurvivalMovementMultiplier()
 		* CalculateCarryWeightMovementMultiplier()
+		* CalculateStanceMovementMultiplier()
 		* FMath::Clamp(TerrainMovementMultiplier, 0.25f, 1.25f),
 		0.15f,
 		1.35f);
@@ -353,11 +425,36 @@ float AAgrarianGameCharacter::CalculateCarryWeightMovementMultiplier() const
 		CurrentCarryWeight);
 }
 
+float AAgrarianGameCharacter::CalculateStanceMovementMultiplier() const
+{
+	if (bIsProne)
+	{
+		return FMath::Clamp(ProneSpeedMultiplier, 0.05f, 1.0f);
+	}
+
+	if (bIsCrouched)
+	{
+		return FMath::Clamp(CrouchSpeedMultiplier, 0.1f, 1.0f);
+	}
+
+	return 1.0f;
+}
+
 void AAgrarianGameCharacter::OnRep_SprintState()
 {
 	ApplyMovementSpeed();
 }
 
+void AAgrarianGameCharacter::OnRep_ProneState()
+{
+	if (bIsProne)
+	{
+		UnCrouch();
+	}
+
+	ApplyMovementSpeed();
+}
+
 void AAgrarianGameCharacter::DoMove(float Right, float Forward)
 {
 	if (GetController() != nullptr)
@@ -448,6 +545,11 @@ void AAgrarianGameCharacter::ServerSetWantsToSprint_Implementation(bool bNewWant
 	SetWantsToSprint(bNewWantsToSprint);
 }
 
+void AAgrarianGameCharacter::ServerSetProne_Implementation(bool bNewProne)
+{
+	SetProne(bNewProne);
+}
+
 void AAgrarianGameCharacter::ServerInteract_Implementation(AActor* TargetActor)
 {
 	if (!TargetActor || !TargetActor->GetClass()->ImplementsInterface(UAgrarianInteractable::StaticClass()))

Source/AgrarianGame/AgrarianGameCharacter.h

@@ -77,6 +77,14 @@ protected:
 	UPROPERTY(EditAnywhere, Category="Input")
 	UInputAction* SprintAction;
 
+	/** Toggle crouch movement stance. */
+	UPROPERTY(EditAnywhere, Category="Input")
+	UInputAction* CrouchAction;
+
+	/** Toggle prone movement stance. */
+	UPROPERTY(EditAnywhere, Category="Input")
+	UInputAction* ProneAction;
+
 	/** Toggle between third-person and first-person camera views. */
 	UPROPERTY(EditAnywhere, Category="Input")
 	UInputAction* ToggleCameraAction;
@@ -101,6 +109,14 @@ protected:
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category="Agrarian|Movement", meta = (ClampMin = "0", ClampMax = "100"))
 	float MinSprintStamina = 5.0f;
 
+	/** Movement multiplier while crouched. */
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category="Agrarian|Movement|Stance", meta = (ClampMin = "0.1", ClampMax = "1"))
+	float CrouchSpeedMultiplier = 0.55f;
+
+	/** Movement multiplier while prone. */
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category="Agrarian|Movement|Stance", meta = (ClampMin = "0.05", ClampMax = "1"))
+	float ProneSpeedMultiplier = 0.25f;
+
 	/** Age hook used by movement until full lifecycle/aging systems own it. */
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Replicated, Category="Agrarian|Movement|Modifiers", meta = (ClampMin = "0"))
 	float AgeYears = 25.0f;
@@ -145,6 +161,10 @@ protected:
 	UPROPERTY(ReplicatedUsing = OnRep_SprintState, VisibleAnywhere, BlueprintReadOnly, Category="Agrarian|Movement", meta = (AllowPrivateAccess = "true"))
 	bool bWantsToSprint = false;
 
+	/** Replicated prone stance for low crawl movement. */
+	UPROPERTY(ReplicatedUsing = OnRep_ProneState, VisibleAnywhere, BlueprintReadOnly, Category="Agrarian|Movement|Stance", meta = (AllowPrivateAccess = "true"))
+	bool bIsProne = false;
+
 public:
 
 	/** Constructor */
@@ -175,6 +195,12 @@ protected:
 	/** Called when sprint input is released. */
 	void StopSprint();
 
+	/** Called when crouch input is pressed. */
+	void ToggleCrouchStance();
+
+	/** Called when prone input is pressed. */
+	void ToggleProneStance();
+
 	/** Called for camera perspective toggle input */
 	void ToggleCameraPerspective();
 
@@ -196,10 +222,14 @@ protected:
 	float CalculateAgeMovementMultiplier() const;
 	float CalculateSurvivalMovementMultiplier() const;
 	float CalculateCarryWeightMovementMultiplier() const;
+	float CalculateStanceMovementMultiplier() const;
 
 	UFUNCTION()
 	void OnRep_SprintState();
 
+	UFUNCTION()
+	void OnRep_ProneState();
+
 public:
 
 	/** Handles move inputs from either controls or UI interfaces */
@@ -230,6 +260,12 @@ public:
 	UFUNCTION(BlueprintPure, Category="Agrarian|Movement")
 	bool IsSprinting() const;
 
+	UFUNCTION(BlueprintPure, Category="Agrarian|Movement|Stance")
+	bool IsProne() const { return bIsProne; }
+
+	UFUNCTION(BlueprintCallable, Category="Agrarian|Movement|Stance")
+	void SetProne(bool bNewProne);
+
 	UFUNCTION(BlueprintPure, Category="Agrarian|Movement")
 	float GetCurrentCarryWeight() const;
 
@@ -247,6 +283,10 @@ public:
 	UFUNCTION(Server, Reliable)
 	void ServerSetWantsToSprint(bool bNewWantsToSprint);
 
+	/** Server-authoritative prone stance update. */
+	UFUNCTION(Server, Reliable)
+	void ServerSetProne(bool bNewProne);
+
 public:
 
 	/** Returns CameraBoom subobject **/