Spawn a border around the world atlas for now

Also spawn the rover within a single chunk in the middle

pkg/game/atlas.go

@@ -46,6 +46,26 @@ func NewAtlas(size int, chunkSize int) Atlas {
 	return a
 }
 
+// SpawnAtlasBorder surrounds the current atlas in a border wall
+func (a *Atlas) SpawnAtlasBorder() error {
+	extent := a.ChunkSize * (a.Size / 2)
+	// Surround the atlas in walls
+	for i := -extent; i < extent; i++ {
+
+		if err := a.SetTile(Vector{i, extent - 1}, TileWall); err != nil {
+			return err
+		} else if a.SetTile(Vector{extent - 1, i}, TileWall); err != nil {
+			return err
+		} else if a.SetTile(Vector{-extent, i}, TileWall); err != nil {
+			return err
+		} else if a.SetTile(Vector{i, extent - 1}, TileWall); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
 // SetTile sets an individual tile's kind
 func (a *Atlas) SetTile(v Vector, tile Tile) error {
 	chunk := a.ToChunk(v)

pkg/game/atlas_test.go

@@ -134,3 +134,27 @@ func TestAtlas_Grown(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, Tile(3), tile)
 }
+
+func TestAtlas_SpawnAtlasBorder(t *testing.T) {
+	// Start with a small example
+	a := NewAtlas(2, 2)
+	assert.NotNil(t, a)
+	assert.Equal(t, 4, len(a.Chunks))
+
+	assert.NoError(t, a.SpawnAtlasBorder())
+	tile, err := a.GetTile(Vector{0, 0})
+	assert.NoError(t, err)
+	assert.Equal(t, TileEmpty, tile)
+
+	tile, err = a.GetTile(Vector{1, 1})
+	assert.NoError(t, err)
+	assert.Equal(t, TileWall, tile)
+
+	tile, err = a.GetTile(Vector{-1, -1})
+	assert.NoError(t, err)
+	assert.Equal(t, TileEmpty, tile)
+
+	tile, err = a.GetTile(Vector{-2, -2})
+	assert.NoError(t, err)
+	assert.Equal(t, TileWall, tile)
+}

pkg/game/tile.go

@@ -4,7 +4,7 @@ package game
 type Tile byte
 
 const (
-	TileEmpty = '_'
+	TileEmpty = Tile(0)
 
-	TileRock = 'o'
+	TileWall = Tile(1)
 )

pkg/game/world.go

@@ -32,10 +32,15 @@ func NewWorld() *World {
 	return &World{
 		Rovers:       make(map[uuid.UUID]Rover),
 		CommandQueue: make(map[uuid.UUID]CommandStream),
-		Atlas:        NewAtlas(2, 8), // TODO: Choose an appropriate world size
+		Atlas:        NewAtlas(4, 8), // TODO: Choose an appropriate world size
 	}
 }
 
+// SpawnWorldBorder spawns a border at the edge of the world atlas
+func (w *World) SpawnWorldBorder() error {
+	return w.Atlas.SpawnAtlasBorder()
+}
+
 // SpawnRover adds an rover to the game
 func (w *World) SpawnRover() uuid.UUID {
 	w.worldMutex.Lock()
@@ -56,8 +61,8 @@ func (w *World) SpawnRover() uuid.UUID {
 
 	// Spawn in a random place near the origin
 	rover.Attributes.Pos = Vector{
-		10 - (rand.Int() % 20),
-		10 - (rand.Int() % 20),
+		w.Atlas.ChunkSize - (rand.Int() % (w.Atlas.ChunkSize * 2)),
+		w.Atlas.ChunkSize - (rand.Int() % (w.Atlas.ChunkSize * 2)),
 	}
 
 	// TODO: Verify no blockages in this area