6 files changed, 98 insertions(+), 8 deletions(-)

M combat_test.go
M main.go
M render.go
M ship.go
M tiles.go
M tiles_test.go

@@ 145,7 145,7 @@ func TestUpdateCombat_hitFlashTicksDown(t *testing.T) {
 	rng := rand.New(rand.NewSource(42))
 	sys := NewStartingSystems() // all power 0 — no weapons, no enemy fire crosses interval
 	c := NewCombat()
-	c.Player.HitFlashT = 0.05
+	c.Player.HitFlashT = 0.01
 	c.Enemy.HitFlashT = 0.15
 	updateCombat(&c, sys, 1.0/60.0, rng)
 	if c.Player.HitFlashT != 0 {

@@ 13,6 13,7 @@ import (
 type Game struct {
 	ship         Ship
 	walk         map[[2]int]bool
+	cells        map[[2]int]bool
 	crew         []Crew
 	selectedCrew int
 	lastTime     time.Time


@@ 75,9 76,13 @@ func (g *Game) Update() error {
 			}
 		}
 
-		if g.selectedCrew >= 0 && g.walk[[2]int{tx, ty}] {
+		if g.selectedCrew >= 0 && g.cells[[2]int{tx, ty}] {
+			dest := [2]int{tx, ty}
+			if g.cellOccupied(dest, g.selectedCrew) {
+				return nil
+			}
 			from := [2]int{g.crew[g.selectedCrew].TileX, g.crew[g.selectedCrew].TileY}
-			g.crew[g.selectedCrew].Path = bfsPath(g.walk, from, [2]int{tx, ty})
+			g.crew[g.selectedCrew].Path = bfsPath(g.walk, from, dest)
 			g.crew[g.selectedCrew].MoveT = 0
 		}
 	}


@@ 99,6 104,18 @@ func (g *Game) Update() error {
 	return nil
 }
 
+func (g *Game) cellOccupied(cell [2]int, excludeCrew int) bool {
+	for i, c := range g.crew {
+		if i == excludeCrew {
+			continue
+		}
+		if len(c.Path) == 0 && c.TileX == cell[0] && c.TileY == cell[1] {
+			return true
+		}
+	}
+	return false
+}
+
 // Draw renders the whole frame.
 func (g *Game) Draw(screen *ebiten.Image) {
 	screen.Fill(color.RGBA{10, 15, 25, 255})


@@ 123,6 140,7 @@ func (g *Game) Layout(_, _ int) (int, int) {
 func main() {
 	ship := NewPlayerShip()
 	walk := walkableTiles(ship)
+	cells := cellSet(ship)
 	crew := NewStartingCrew()
 	systems := NewStartingSystems()
 	combat := NewCombat()


@@ 133,6 151,7 @@ func main() {
 	if err := ebiten.RunGame(&Game{
 		ship:         ship,
 		walk:         walk,
+		cells:        cells,
 		crew:         crew,
 		selectedCrew: -1,
 		systems:      systems,

@@ 111,6 111,13 @@ func drawRoom(screen *ebiten.Image, r Room, powered bool) {
 
 	// Label: a few pixels inside the top-left corner.
 	ebitenutil.DebugPrintAt(screen, r.Name, int(x)+3, int(y)+2)
+
+	// Cell markers: small dim squares at cell positions.
+	for _, c := range r.Cells {
+		cx := float32(c[0]*TilePx + TilePx/2 - 2)
+		cy := float32(c[1]*TilePx + TilePx/2 - 2)
+		vector.DrawFilledRect(screen, cx, cy, 4, 4, color.RGBA{255, 255, 255, 60}, false)
+	}
 }
 
 // drawHullBars renders hull readouts for both sides.

@@ 24,6 24,7 @@ type Room struct {
 	GridW int
 	GridH int
 	Role  RoomRole
+	Cells [][2]int
 }
 
 // Ship is a pure-data description of a ship layout.


@@ 39,6 40,11 @@ func NewEnemyShip() Ship {
 	rooms := make([]Room, len(player.Rooms))
 	for i, r := range player.Rooms {
 		r.GridX += 24
+		shifted := make([][2]int, len(r.Cells))
+		for j, c := range r.Cells {
+			shifted[j] = [2]int{c[0] + 24, c[1]}
+		}
+		r.Cells = shifted
 		rooms[i] = r
 	}
 	return Ship{Rooms: rooms}


@@ 50,11 56,16 @@ func NewEnemyShip() Ship {
 func NewPlayerShip() Ship {
 	return Ship{
 		Rooms: []Room{
-			{ID: 1, Name: "Pilot", GridX: 3, GridY: 9, GridW: 3, GridH: 3, Role: RolePilot},
-			{ID: 2, Name: "Weapons", GridX: 6, GridY: 6, GridW: 4, GridH: 3, Role: RoleWeapons},
-			{ID: 3, Name: "Shields", GridX: 6, GridY: 9, GridW: 4, GridH: 3, Role: RoleShields},
-			{ID: 4, Name: "MedBay", GridX: 6, GridY: 12, GridW: 4, GridH: 3, Role: RoleMedBay},
-			{ID: 5, Name: "Engines", GridX: 10, GridY: 9, GridW: 3, GridH: 3, Role: RoleEngines},
+			{ID: 1, Name: "Pilot", GridX: 3, GridY: 9, GridW: 3, GridH: 3, Role: RolePilot,
+				Cells: [][2]int{{4, 10}, {5, 10}}},
+			{ID: 2, Name: "Weapons", GridX: 6, GridY: 6, GridW: 4, GridH: 3, Role: RoleWeapons,
+				Cells: [][2]int{{7, 7}, {8, 7}}},
+			{ID: 3, Name: "Shields", GridX: 6, GridY: 9, GridW: 4, GridH: 3, Role: RoleShields,
+				Cells: [][2]int{{7, 10}, {8, 10}}},
+			{ID: 4, Name: "MedBay", GridX: 6, GridY: 12, GridW: 4, GridH: 3, Role: RoleMedBay,
+				Cells: [][2]int{{7, 13}, {8, 13}}},
+			{ID: 5, Name: "Engines", GridX: 10, GridY: 9, GridW: 3, GridH: 3, Role: RoleEngines,
+				Cells: [][2]int{{11, 10}, {12, 10}}},
 		},
 	}
 }

@@ 12,6 12,16 @@ func walkableTiles(s Ship) map[[2]int]bool {
 	return walk
 }
 
+func cellSet(s Ship) map[[2]int]bool {
+	cells := make(map[[2]int]bool)
+	for _, r := range s.Rooms {
+		for _, c := range r.Cells {
+			cells[c] = true
+		}
+	}
+	return cells
+}
+
 func bfsPath(walk map[[2]int]bool, from, to [2]int) [][2]int {
 	if from == to {
 		return nil

@@ 41,6 41,49 @@ func TestWalkableTiles_ignoresOutside(t *testing.T) {
 	}
 }
 
+func TestCellSet_returnsAllCells(t *testing.T) {
+	s := NewPlayerShip()
+	cells := cellSet(s)
+	if len(cells) != 10 {
+		t.Fatalf("expected 10 cells (2 per room × 5 rooms), got %d", len(cells))
+	}
+	expected := [][2]int{
+		{4, 10}, {5, 10},
+		{7, 7}, {8, 7},
+		{7, 10}, {8, 10},
+		{7, 13}, {8, 13},
+		{11, 10}, {12, 10},
+	}
+	for _, c := range expected {
+		if !cells[c] {
+			t.Errorf("expected cell %v to be present", c)
+		}
+	}
+}
+
+func TestCellSet_allWalkable(t *testing.T) {
+	s := NewPlayerShip()
+	walk := walkableTiles(s)
+	cells := cellSet(s)
+	for c := range cells {
+		if !walk[c] {
+			t.Errorf("cell %v is not walkable", c)
+		}
+	}
+}
+
+func TestCellSet_startingCrewOnCells(t *testing.T) {
+	s := NewPlayerShip()
+	cells := cellSet(s)
+	crew := NewStartingCrew()
+	for _, c := range crew {
+		pos := [2]int{c.TileX, c.TileY}
+		if !cells[pos] {
+			t.Errorf("crew %s at %v is not on a cell", c.Name, pos)
+		}
+	}
+}
+
 func TestBFSPath_sameTile(t *testing.T) {
 	s := NewPlayerShip()
 	walk := walkableTiles(s)