Add units with placement, reachable range display, and movement

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

Source/Tactica/Private/GridCell.cpp

@@ -48,6 +48,12 @@ void AGridCell::BeginPlay()
 	RefreshColor();
 }
 
+void AGridCell::SetInRange(bool bInInRange)
+{
+	bInRange = bInInRange;
+	RefreshColor();
+}
+
 void AGridCell::SetHovered(bool bInHovered)
 {
 	bHovered = bInHovered;
@@ -64,7 +70,9 @@ void AGridCell::RefreshColor()
 {
 	if (DynamicMaterial)
 	{
-		const FLinearColor& Color = bSelected ? SelectedColor : (bHovered ? HoverColor : NormalColor);
+		// 優先順位: 選択 > ホバー > 移動可能 > 通常
+		const FLinearColor& Color = bSelected ? SelectedColor
+			: (bHovered ? HoverColor : (bInRange ? RangeColor : NormalColor));
 		DynamicMaterial->SetVectorParameterValue(TEXT("Color"), Color);
 	}
 }

Source/Tactica/Private/GridManager.cpp

@@ -1,6 +1,8 @@
 #include "GridManager.h"
 #include "GridCell.h"
 #include "GridMath.h"
+#include "GridPathfinder.h"
+#include "Unit.h"
 #include "Engine/World.h"
 
 // このファイル専用のログカテゴリ
@@ -51,6 +53,7 @@ void AGridManager::GenerateGrid()
 	}
 
 	Cells.Reset();
+	GridState.Init(GridSizeX, GridSizeY);
 	const FVector Origin = GetActorLocation();
 
 	for (int32 Y = 0; Y < GridSizeY; ++Y)
@@ -70,6 +73,8 @@ void AGridManager::GenerateGrid()
 			{
 				Cell->GridCoord = FIntPoint(X, Y);
 				Cells.Add(Cell);
+				// 論理データへ歩行可否をコピー(以後は GridState が正)
+				GridState.SetWalkable(Cell->GridCoord, Cell->bIsWalkable);
 			}
 			else
 			{
@@ -79,4 +84,116 @@ void AGridManager::GenerateGrid()
 	}
 
 	UE_LOG(LogTacticaGrid, Log, TEXT("%d 個のマスを生成しました"), Cells.Num());
+
+	SpawnUnits();
+}
+
+void AGridManager::SpawnUnits()
+{
+	UWorld* World = GetWorld();
+	if (!World)
+	{
+		return;
+	}
+
+	if (!UnitClass)
+	{
+		UnitClass = AUnit::StaticClass();
+	}
+
+	Units.Reset();
+	NextUnitId = 0;
+	const FVector Origin = GetActorLocation();
+
+	for (const FIntPoint& Coord : InitialUnitCoords)
+	{
+		const int32 UnitId = NextUnitId;
+
+		// 先に論理側で配置できるか確認する(範囲外・歩行不可・占有済みなら失敗)
+		const FGridCellData* Cell = GridState.GetCell(Coord);
+		if (!Cell || !Cell->bWalkable || Cell->OccupantId != INDEX_NONE)
+		{
+			UE_LOG(LogTacticaGrid, Warning, TEXT("ユニットを (%d, %d) に配置できません(範囲外・歩行不可・占有済み)"),
+				Coord.X, Coord.Y);
+			continue;
+		}
+
+		FActorSpawnParameters Params;
+		Params.SpawnCollisionHandlingOverride = ESpawnActorCollisionHandlingMethod::AlwaysSpawn;
+
+		AUnit* Unit = World->SpawnActor<AUnit>(
+			UnitClass, FGridMath::CellToWorld(Coord, Origin, CellSize), FRotator::ZeroRotator, Params);
+		if (!Unit)
+		{
+			UE_LOG(LogTacticaGrid, Warning, TEXT("ユニットの生成に失敗 (%d, %d)"), Coord.X, Coord.Y);
+			continue;
+		}
+
+		GridState.PlaceUnit(UnitId, Coord);
+		Unit->UnitId = UnitId;
+		Unit->GridCoord = Coord;
+		Units.Add(Unit);
+		++NextUnitId;
+	}
+
+	UE_LOG(LogTacticaGrid, Log, TEXT("%d 体のユニットを配置しました"), Units.Num());
+}
+
+AUnit* AGridManager::GetUnitAt(FIntPoint Coord) const
+{
+	const int32 UnitId = GridState.GetOccupant(Coord);
+	if (UnitId == INDEX_NONE)
+	{
+		return nullptr;
+	}
+	for (AUnit* Unit : Units)
+	{
+		if (Unit && Unit->UnitId == UnitId)
+		{
+			return Unit;
+		}
+	}
+	return nullptr;
+}
+
+bool AGridManager::TryMoveUnit(AUnit* Unit, FIntPoint Dest, const FGridReachResult& Reach)
+{
+	if (!Unit)
+	{
+		return false;
+	}
+
+	const TArray<FIntPoint> Path = FGridPathfinder::BuildPath(Reach, Unit->GridCoord, Dest);
+	if (Path.Num() == 0)
+	{
+		return false;
+	}
+
+	// 占有情報は移動の開始時に確定させる(見た目は後から追いかける)
+	if (!GridState.MoveUnit(Unit->UnitId, Unit->GridCoord, Dest))
+	{
+		return false;
+	}
+
+	const FVector Origin = GetActorLocation();
+	TArray<FVector> Waypoints;
+	for (const FIntPoint& Coord : Path)
+	{
+		Waypoints.Add(FGridMath::CellToWorld(Coord, Origin, CellSize));
+	}
+
+	Unit->GridCoord = Dest;
+	Unit->MoveAlongPath(Waypoints);
+	return true;
+}
+
+void AGridManager::SetRangeHighlight(const TArray<FIntPoint>& Coords, bool bInRange)
+{
+	for (const FIntPoint& Coord : Coords)
+	{
+		if (AGridCell* Cell = GetCellAt(Coord))
+		{
+			Cell->SetInRange(bInRange);
+		}
+	}
 }

Source/Tactica/Private/GridPathfinder.cpp

@@ -0,0 +1,91 @@
+#include "GridPathfinder.h"
+#include "GridState.h"
+#include "Algo/Reverse.h"
+
+int32 FGridPathfinder::GetStepCost(const FGridState& State, FIntPoint From, FIntPoint To)
+{
+	return 1;
+}
+
+FGridReachResult FGridPathfinder::FindReachable(const FGridState& State, FIntPoint Start, int32 MaxCost)
+{
+	FGridReachResult Result;
+	if (!State.IsInBounds(Start) || MaxCost < 0)
+	{
+		return Result;
+	}
+
+	static const FIntPoint Directions[4] = {
+		FIntPoint(1, 0), FIntPoint(-1, 0), FIntPoint(0, 1), FIntPoint(0, -1) };
+
+	Result.Cost.Add(Start, 0);
+
+	// 未確定のマス。グリッドは小さいので、最小コストの線形探索で十分
+	TArray<FIntPoint> Open;
+	Open.Add(Start);
+
+	while (Open.Num() > 0)
+	{
+		// コスト最小のマスを取り出して確定する
+		int32 BestIndex = 0;
+		for (int32 i = 1; i < Open.Num(); ++i)
+		{
+			if (Result.Cost[Open[i]] < Result.Cost[Open[BestIndex]])
+			{
+				BestIndex = i;
+			}
+		}
+		const FIntPoint Current = Open[BestIndex];
+		Open.RemoveAtSwap(BestIndex);
+		const int32 CurrentCost = Result.Cost[Current];
+
+		for (const FIntPoint& Dir : Directions)
+		{
+			const FIntPoint Next = Current + Dir;
+			const FGridCellData* Cell = State.GetCell(Next);
+			if (!Cell || !Cell->bWalkable || Cell->OccupantId != INDEX_NONE)
+			{
+				continue;
+			}
+
+			const int32 NewCost = CurrentCost + GetStepCost(State, Current, Next);
+			if (NewCost > MaxCost)
+			{
+				continue;
+			}
+
+			const int32* OldCost = Result.Cost.Find(Next);
+			if (!OldCost || NewCost < *OldCost)
+			{
+				Result.Cost.Add(Next, NewCost);
+				Result.Parent.Add(Next, Current);
+				Open.AddUnique(Next);
+			}
+		}
+	}
+
+	return Result;
+}
+
+TArray<FIntPoint> FGridPathfinder::BuildPath(const FGridReachResult& Reach, FIntPoint Start, FIntPoint Goal)
+{
+	TArray<FIntPoint> Path;
+	if (Start == Goal || !Reach.IsReachable(Goal))
+	{
+		return Path;
+	}
+
+	FIntPoint Current = Goal;
+	while (Current != Start)
+	{
+		Path.Add(Current);
+		const FIntPoint* Parent = Reach.Parent.Find(Current);
+		if (!Parent)
+		{
+			return TArray<FIntPoint>(); // 起点に戻れない(通常は起きない)
+		}
+		Current = *Parent;
+	}
+	Algo::Reverse(Path);
+	return Path;
+}

Source/Tactica/Private/GridState.cpp

@@ -0,0 +1,73 @@
+#include "GridState.h"
+#include "GridMath.h"
+
+void FGridState::Init(int32 InSizeX, int32 InSizeY)
+{
+	SizeX = FMath::Max(InSizeX, 0);
+	SizeY = FMath::Max(InSizeY, 0);
+	Cells.Reset();
+	Cells.SetNum(SizeX * SizeY);
+}
+
+bool FGridState::IsInBounds(FIntPoint Coord) const
+{
+	return FGridMath::IsInBounds(Coord, SizeX, SizeY);
+}
+
+const FGridCellData* FGridState::GetCell(FIntPoint Coord) const
+{
+	const int32 Index = FGridMath::CoordToIndex(Coord, SizeX, SizeY);
+	return Cells.IsValidIndex(Index) ? &Cells[Index] : nullptr;
+}
+
+FGridCellData* FGridState::GetCellMutable(FIntPoint Coord)
+{
+	const int32 Index = FGridMath::CoordToIndex(Coord, SizeX, SizeY);
+	return Cells.IsValidIndex(Index) ? &Cells[Index] : nullptr;
+}
+
+void FGridState::SetWalkable(FIntPoint Coord, bool bWalkable)
+{
+	if (FGridCellData* Cell = GetCellMutable(Coord))
+	{
+		Cell->bWalkable = bWalkable;
+	}
+}
+
+int32 FGridState::GetOccupant(FIntPoint Coord) const
+{
+	const FGridCellData* Cell = GetCell(Coord);
+	return Cell ? Cell->OccupantId : INDEX_NONE;
+}
+
+bool FGridState::PlaceUnit(int32 UnitId, FIntPoint Coord)
+{
+	FGridCellData* Cell = GetCellMutable(Coord);
+	if (!Cell || !Cell->bWalkable || Cell->OccupantId != INDEX_NONE)
+	{
+		return false;
+	}
+	Cell->OccupantId = UnitId;
+	return true;
+}
+
+bool FGridState::MoveUnit(int32 UnitId, FIntPoint From, FIntPoint To)
+{
+	FGridCellData* FromCell = GetCellMutable(From);
+	FGridCellData* ToCell = GetCellMutable(To);
+	if (!FromCell || !ToCell || FromCell->OccupantId != UnitId)
+	{
+		return false;
+	}
+	if (From == To)
+	{
+		return true;
+	}
+	if (!ToCell->bWalkable || ToCell->OccupantId != INDEX_NONE)
+	{
+		return false;
+	}
+	FromCell->OccupantId = INDEX_NONE;
+	ToCell->OccupantId = UnitId;
+	return true;
+}

Source/Tactica/Private/TacticaPlayerController.cpp

@@ -1,7 +1,10 @@
 #include "TacticaPlayerController.h"
 #include "GridCell.h"
+#include "GridManager.h"
+#include "Unit.h"
 #include "Components/InputComponent.h"
 #include "InputCoreTypes.h"
+#include "Kismet/GameplayStatics.h"
 
 DEFINE_LOG_CATEGORY_STATIC(LogTacticaInput, Log, All);
 
@@ -57,21 +60,116 @@ AGridCell* ATacticaPlayerController::GetCellUnderCursor() const
 	return nullptr;
 }
 
+AGridManager* ATacticaPlayerController::GetGridManager()
+{
+	if (!GridManager)
+	{
+		GridManager = Cast<AGridManager>(
+			UGameplayStatics::GetActorOfClass(this, AGridManager::StaticClass()));
+	}
+	return GridManager;
+}
+
 void ATacticaPlayerController::OnClick()
 {
-	AGridCell* Cell = GetCellUnderCursor();
-	if (!Cell)
+	if (State == EState::Moving)
 	{
-		return; // マス以外のクリックでは選択を変えない
+		UE_LOG(LogTacticaInput, Log, TEXT("移動中のため入力を無視しました"));
+		return;
 	}
 
+	AGridCell* Cell = GetCellUnderCursor();
+	AGridManager* Grid = GetGridManager();
+	if (!Cell || !Grid)
+	{
+		return; // マス以外のクリックでは何も変えない
+	}
+
+	const FIntPoint Coord = Cell->GridCoord;
+	UE_LOG(LogTacticaInput, Log, TEXT("Cell clicked: (%d, %d)"), Coord.X, Coord.Y);
+
+	if (State == EState::Idle)
+	{
+		if (AUnit* Unit = Grid->GetUnitAt(Coord))
+		{
+			SelectUnit(Unit, Cell);
+		}
+		else
+		{
+			UE_LOG(LogTacticaInput, Log, TEXT("(%d, %d) にユニットはいません"), Coord.X, Coord.Y);
+		}
+		return;
+	}
+
+	// UnitSelected: 移動可能なマス(起点を除く)だけ受け付ける
+	if (SelectedUnit && Coord != SelectedUnit->GridCoord && ReachResult.IsReachable(Coord))
+	{
+		if (Grid->TryMoveUnit(SelectedUnit, Coord, ReachResult))
+		{
+			State = EState::Moving;
+			SelectedUnit->OnMoveFinished.AddUObject(this, &ATacticaPlayerController::OnUnitMoveFinished);
+			UE_LOG(LogTacticaInput, Log, TEXT("ユニット %d を (%d, %d) へ移動開始"),
+				SelectedUnit->UnitId, Coord.X, Coord.Y);
+			return;
+		}
+	}
+
+	UE_LOG(LogTacticaInput, Log, TEXT("(%d, %d) には移動できません"), Coord.X, Coord.Y);
+}
+
+void ATacticaPlayerController::SelectUnit(AUnit* Unit, AGridCell* Cell)
+{
+	AGridManager* Grid = GetGridManager();
+	if (!Unit || !Cell || !Grid)
+	{
+		return;
+	}
+
+	SelectedUnit = Unit;
+	SelectedCell = Cell;
+	SelectedCell->SetSelected(true);
+
+	ReachResult = FGridPathfinder::FindReachable(Grid->GetGridState(), Unit->GridCoord, Unit->Stats.MoveRange);
+
+	RangeCoords.Reset();
+	for (const TPair<FIntPoint, int32>& Pair : ReachResult.Cost)
+	{
+		if (Pair.Key != Unit->GridCoord)
+		{
+			RangeCoords.Add(Pair.Key);
+		}
+	}
+	Grid->SetRangeHighlight(RangeCoords, true);
+
+	State = EState::UnitSelected;
+	UE_LOG(LogTacticaInput, Log, TEXT("ユニット %d を選択 (移動力 %d, 移動可能 %d マス)"),
+		Unit->UnitId, Unit->Stats.MoveRange, RangeCoords.Num());
+}
+
+void ATacticaPlayerController::ClearSelection()
+{
+	if (AGridManager* Grid = GetGridManager())
+	{
+		Grid->SetRangeHighlight(RangeCoords, false);
+	}
+	RangeCoords.Reset();
+	ReachResult = FGridReachResult();
+
 	if (SelectedCell)
 	{
 		SelectedCell->SetSelected(false);
 	}
-	SelectedCell = Cell;
-	SelectedCell->SetSelected(true);
-
-	UE_LOG(LogTacticaInput, Log, TEXT("Cell clicked: (%d, %d)"),
-		Cell->GridCoord.X, Cell->GridCoord.Y);
+	SelectedCell = nullptr;
+	SelectedUnit = nullptr;
+	State = EState::Idle;
+}
+
+void ATacticaPlayerController::OnUnitMoveFinished()
+{
+	if (SelectedUnit)
+	{
+		SelectedUnit->OnMoveFinished.RemoveAll(this);
+		UE_LOG(LogTacticaInput, Log, TEXT("ユニット %d の移動完了"), SelectedUnit->UnitId);
+	}
+	ClearSelection();
 }

Source/Tactica/Private/Unit.cpp

@@ -0,0 +1,71 @@
+#include "Unit.h"
+#include "Components/StaticMeshComponent.h"
+#include "Engine/StaticMesh.h"
+#include "UObject/ConstructorHelpers.h"
+
+AUnit::AUnit()
+{
+	// Tickは移動中だけ有効にする
+	PrimaryActorTick.bCanEverTick = true;
+	PrimaryActorTick.bStartWithTickEnabled = false;
+
+	USceneComponent* Root = CreateDefaultSubobject<USceneComponent>(TEXT("Root"));
+	SetRootComponent(Root);
+
+	MeshComponent = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("MeshComponent"));
+	MeshComponent->SetupAttachment(Root);
+
+	// 仮の見た目: 標準のシリンダー(100x100x100cm)を細くする
+	static ConstructorHelpers::FObjectFinder<UStaticMesh> CylinderAsset(
+		TEXT("/Engine/BasicShapes/Cylinder.Cylinder"));
+	if (CylinderAsset.Succeeded())
+	{
+		MeshComponent->SetStaticMesh(CylinderAsset.Object);
+	}
+	MeshComponent->SetRelativeScale3D(FVector(0.4f, 0.4f, 1.0f));
+	// 底面がActorの原点(マスの上面)に来るよう、高さの半分(50cm)上げる
+	MeshComponent->SetRelativeLocation(FVector(0.0f, 0.0f, 50.0f));
+
+	// マスのクリック判定をユニットが邪魔しないよう、当たり判定は無効にする
+	MeshComponent->SetCollisionEnabled(ECollisionEnabled::NoCollision);
+}
+
+void AUnit::MoveAlongPath(const TArray<FVector>& InWaypoints)
+{
+	Waypoints = InWaypoints;
+	WaypointIndex = 0;
+
+	if (Waypoints.Num() == 0)
+	{
+		OnMoveFinished.Broadcast();
+		return;
+	}
+	SetActorTickEnabled(true);
+}
+
+void AUnit::Tick(float DeltaTime)
+{
+	Super::Tick(DeltaTime);
+
+	if (!IsMoving())
+	{
+		SetActorTickEnabled(false);
+		return;
+	}
+
+	const FVector Target = Waypoints[WaypointIndex];
+	const FVector NewLocation = FMath::VInterpConstantTo(GetActorLocation(), Target, DeltaTime, MoveSpeed);
+	SetActorLocation(NewLocation);
+
+	if (NewLocation.Equals(Target, 0.1f))
+	{
+		++WaypointIndex;
+		if (!IsMoving())
+		{
+			Waypoints.Reset();
+			WaypointIndex = 0;
+			SetActorTickEnabled(false);
+			OnMoveFinished.Broadcast();
+		}
+	}
+}

Source/Tactica/Public/GridCell.h

@@ -43,6 +43,11 @@ public:
 	UPROPERTY(EditAnywhere, Category = "Grid|Highlight")
 	FLinearColor SelectedColor = FLinearColor(0.1f, 0.6f, 1.0f);
 
+	// 移動可能範囲の色
+	UPROPERTY(EditAnywhere, Category = "Grid|Highlight")
+	FLinearColor RangeColor = FLinearColor(0.2f, 0.8f, 0.3f);
+
+	void SetInRange(bool bInInRange);
 	void SetHovered(bool bInHovered);
 	void SetSelected(bool bInSelected);
 
@@ -53,6 +58,7 @@ private:
 	// 状態から色を決めて反映する(優先順位: 選択 > ホバー > 通常)
 	void RefreshColor();
 
+	bool bInRange = false;
 	bool bHovered = false;
 	bool bSelected = false;
 

Source/Tactica/Public/GridManager.h

@@ -2,9 +2,12 @@
 
 #include "CoreMinimal.h"
 #include "GameFramework/Actor.h"
+#include "GridState.h"
 #include "GridManager.generated.h"
 
 class AGridCell;
+class AUnit;
+struct FGridReachResult;
 
 UCLASS()
 class TACTICA_API AGridManager : public AActor
@@ -38,6 +41,31 @@ public:
 	UPROPERTY(VisibleAnywhere, Category = "Grid")
 	TArray<TObjectPtr<AGridCell>> Cells;
 
+	// スポーンするユニットのクラス(未設定ならAUnit)
+	UPROPERTY(EditAnywhere, Category = "Units")
+	TSubclassOf<AUnit> UnitClass;
+
+	// ユニットの初期配置座標(1要素につき1体)
+	UPROPERTY(EditAnywhere, Category = "Units")
+	TArray<FIntPoint> InitialUnitCoords = { FIntPoint(0, 0), FIntPoint(2, 2) };
+
+	// 生成したユニットの一覧
+	UPROPERTY(VisibleAnywhere, Category = "Units")
+	TArray<TObjectPtr<AUnit>> Units;
+
+	// 論理データ(歩行可否・占有)。経路探索などはこれを読む
+	const FGridState& GetGridState() const { return GridState; }
+
+	// 座標にいるユニットを返す(いなければnullptr)
+	AUnit* GetUnitAt(FIntPoint Coord) const;
+
+	// ユニットを Dest へ移動させる。占有情報を更新し、見た目の移動を開始する
+	// Reach は、ユニットの現在位置から求めた FindReachable の結果
+	bool TryMoveUnit(AUnit* Unit, FIntPoint Dest, const FGridReachResult& Reach);
+
+	// 指定したマスの「移動可能」表示をON/OFFする
+	void SetRangeHighlight(const TArray<FIntPoint>& Coords, bool bInRange);
+
 	// 座標のマスを返す(範囲外はnullptr)
 	AGridCell* GetCellAt(FIntPoint Coord) const;
 
@@ -46,4 +74,8 @@ public:
 
 private:
 	void GenerateGrid();
+	void SpawnUnits();
+
+	FGridState GridState;
+	int32 NextUnitId = 0;
 };

Source/Tactica/Public/GridPathfinder.h

@@ -0,0 +1,32 @@
+#pragma once
+
+#include "CoreMinimal.h"
+
+class FGridState;
+
+// 到達可能マスの探索結果
+struct FGridReachResult
+{
+	// 到達可能なマス → 起点からの総コスト(起点自身も0で含む)
+	TMap<FIntPoint, int32> Cost;
+
+	// 各マスへ最短で来るときの1つ前のマス(起点は含まない)
+	TMap<FIntPoint, FIntPoint> Parent;
+
+	bool IsReachable(FIntPoint Coord) const { return Cost.Contains(Coord); }
+};
+
+// 経路探索。UObject/Actorに依存しない純粋なロジック
+struct TACTICA_API FGridPathfinder
+{
+	// 起点から MaxCost 以内で到達できるマスを求める(ダイクストラ、上下左右4方向)
+	// 歩行不可のマス、他ユニットのいるマスは通れない。起点は占有されていてもよい
+	static FGridReachResult FindReachable(const FGridState& State, FIntPoint Start, int32 MaxCost);
+
+	// 探索結果から Start → Goal の経路を復元する(起点は含まず、Goalを最後に含む)
+	// 到達不可、または Start == Goal の場合は空
+	static TArray<FIntPoint> BuildPath(const FGridReachResult& Reach, FIntPoint Start, FIntPoint Goal);
+
+	// 隣接マスへ1歩進むコスト。今は常に1。高低差や地形コストを入れるときはここを変える
+	static int32 GetStepCost(const FGridState& State, FIntPoint From, FIntPoint To);
+};

Source/Tactica/Public/GridState.h

@@ -0,0 +1,50 @@
+#pragma once
+
+#include "CoreMinimal.h"
+
+// 1マス分の論理データ(見た目に依存しない)
+struct FGridCellData
+{
+	// 歩行可能か
+	bool bWalkable = true;
+
+	// 高さ(階層)。今は未使用だが経路コストや視線判定で使う予定
+	int32 Height = 0;
+
+	// 占有しているユニットのID(いなければ INDEX_NONE)
+	int32 OccupantId = INDEX_NONE;
+};
+
+// グリッドの論理状態。UObject/Actorに依存しない純粋なC++クラス
+// 経路探索・視線判定・AI評価などから使い回す
+class TACTICA_API FGridState
+{
+public:
+	void Init(int32 InSizeX, int32 InSizeY);
+
+	int32 GetSizeX() const { return SizeX; }
+	int32 GetSizeY() const { return SizeY; }
+
+	bool IsInBounds(FIntPoint Coord) const;
+
+	// 範囲外は nullptr
+	const FGridCellData* GetCell(FIntPoint Coord) const;
+
+	void SetWalkable(FIntPoint Coord, bool bWalkable);
+
+	// 占有しているユニットのID。いない/範囲外は INDEX_NONE
+	int32 GetOccupant(FIntPoint Coord) const;
+
+	// ユニットを配置する。範囲外・歩行不可・占有済みなら false
+	bool PlaceUnit(int32 UnitId, FIntPoint Coord);
+
+	// ユニットを移動する。From に UnitId がいない、To が使えない場合は false
+	bool MoveUnit(int32 UnitId, FIntPoint From, FIntPoint To);
+
+private:
+	FGridCellData* GetCellMutable(FIntPoint Coord);
+
+	int32 SizeX = 0;
+	int32 SizeY = 0;
+	TArray<FGridCellData> Cells;
+};

Source/Tactica/Public/TacticaPlayerController.h

@@ -2,9 +2,12 @@
 
 #include "CoreMinimal.h"
 #include "GameFramework/PlayerController.h"
+#include "GridPathfinder.h"
 #include "TacticaPlayerController.generated.h"
 
 class AGridCell;
+class AGridManager;
+class AUnit;
 
 UCLASS()
 class TACTICA_API ATacticaPlayerController : public APlayerController
@@ -19,16 +22,41 @@ protected:
 	virtual void PlayerTick(float DeltaTime) override;
 
 private:
+	// 操作の状態
+	enum class EState : uint8
+	{
+		Idle,          // 何も選んでいない
+		UnitSelected,  // ユニットを選択中(移動範囲を表示中)
+		Moving         // ユニットが移動中(入力を受け付けない)
+	};
+
 	// カーソル下のマスを返す(なければnullptr)
 	AGridCell* GetCellUnderCursor() const;
 
+	AGridManager* GetGridManager();
+
 	void OnClick();
+	void SelectUnit(AUnit* Unit, AGridCell* Cell);
+	void ClearSelection();
+	void OnUnitMoveFinished();
+
+	EState State = EState::Idle;
 
 	// 現在ホバー中のマス
 	UPROPERTY()
 	TObjectPtr<AGridCell> HoveredCell;
 
-	// 現在選択中のマス
+	// 選択中のユニットと、そのユニットが乗っていたマス
+	UPROPERTY()
+	TObjectPtr<AUnit> SelectedUnit;
+
 	UPROPERTY()
 	TObjectPtr<AGridCell> SelectedCell;
+
+	UPROPERTY()
+	TObjectPtr<AGridManager> GridManager;
+
+	// 選択中ユニットの移動可能範囲(起点を除く)と探索結果
+	TArray<FIntPoint> RangeCoords;
+	FGridReachResult ReachResult;
 };

Source/Tactica/Public/Unit.h

@@ -0,0 +1,50 @@
+#pragma once
+
+#include "CoreMinimal.h"
+#include "GameFramework/Actor.h"
+#include "UnitStats.h"
+#include "Unit.generated.h"
+
+class UStaticMeshComponent;
+
+// ユニット(兵士)。見た目と移動の補間だけを担当し、占有などの論理はAGridManager/FGridStateが持つ
+UCLASS()
+class TACTICA_API AUnit : public AActor
+{
+	GENERATED_BODY()
+
+public:
+	AUnit();
+
+	virtual void Tick(float DeltaTime) override;
+
+	// ユニットID(AGridManagerが割り振る)
+	UPROPERTY(VisibleAnywhere, Category = "Unit")
+	int32 UnitId = INDEX_NONE;
+
+	// 現在いるマスの座標(論理上の位置)
+	UPROPERTY(VisibleAnywhere, Category = "Unit")
+	FIntPoint GridCoord = FIntPoint::ZeroValue;
+
+	UPROPERTY(EditAnywhere, Category = "Unit")
+	FUnitStats Stats;
+
+	// 移動速度(cm/秒)
+	UPROPERTY(EditAnywhere, Category = "Unit")
+	float MoveSpeed = 400.0f;
+
+	// ウェイポイントを順に通って移動する
+	void MoveAlongPath(const TArray<FVector>& InWaypoints);
+
+	bool IsMoving() const { return WaypointIndex < Waypoints.Num(); }
+
+	// 移動完了時に呼ばれる
+	FSimpleMulticastDelegate OnMoveFinished;
+
+private:
+	UPROPERTY(VisibleAnywhere, Category = "Unit")
+	TObjectPtr<UStaticMeshComponent> MeshComponent;
+
+	TArray<FVector> Waypoints;
+	int32 WaypointIndex = 0;
+};

Source/Tactica/Public/UnitStats.h

@@ -0,0 +1,16 @@
+#pragma once
+
+#include "CoreMinimal.h"
+#include "Engine/DataTable.h"
+#include "UnitStats.generated.h"
+
+// ユニットのステータス。将来はDataTableの行として読み込めるようFTableRowBaseを継承する
+USTRUCT(BlueprintType)
+struct FUnitStats : public FTableRowBase
+{
+	GENERATED_BODY()
+
+	// 移動力(マス数)
+	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category = "Unit")
+	int32 MoveRange = 4;
+};