RoomGraph

Class

Source: RoomGraph.h

Inherits from: RoomGraphBase

Description

Fixed-capacity graph of rooms with camera rects and connections.

N Max number of rooms (compile-time constant, must be >= 1).

Zero-heap, zero-allocation. All arrays are fixed-size. The graph is built once in Scene::init() and is read-only thereafter.

Entering a room updates the camera bounds via Camera2D::setBounds / Camera2D::setVerticalBounds and fires an optional onEnter callback. Entity movement across rooms is the game's responsibility — RoomGraph only provides data and camera management.

Inheritance

RoomGraphBase → RoomGraph

Methods

uint16_t addRoom(math::Scalar cameraMinX, math::Scalar cameraMinY, math::Scalar cameraMaxX, math::Scalar cameraMaxY)

Description:

Add a room to the graph.

Parameters:

• cameraMinX: Left camera bound (world units)
• cameraMinY: Top camera bound (world units)
• cameraMaxX: Right camera bound (world units)
• cameraMaxY: Bottom camera bound (world units)

Returns: Room index (0 .. N-1), or 0xFFFF if full.

void setTileWindow(uint16_t roomIdx, int16_t originCol, int16_t originRow, int16_t cols, int16_t rows)

Description:

Set the tile window for a room.

Parameters:

• roomIdx: Room index
• originCol: Tile window origin column
• originRow: Tile window origin row
• cols: Tile window width in tiles
• rows: Tile window height in tiles

No-op when roomIdx is out of range.

void connect(uint16_t fromIdx, uint16_t toIdx, RoomDir dir)

Description:

Connect two rooms in a cardinal direction.

Parameters:

• fromIdx: Source room index
• toIdx: Target room index
• dir: Direction from source to target

No-op when either index is out of range. Re-connecting an already- occupied direction slot does not double-count the connection.

void enterRoom(uint16_t idx, graphics::Camera2D* camera)

Description:

Enter a room by index.

Parameters:

• idx: Room index
• camera: Pointer to Camera2D (may be nullptr)

No-op when idx is out of range.

void setOnEnter(void (*fn)(int fromIdx, int toIdx, void* userData), void* userData = nullptr)

Description:

Register an onEnter callback.

Parameters:

• fn: Plain function pointer (not std::function — zero heap)
• userData: Context pointer passed through to the callback

uint16_t currentRoomIndex() const

Description:

Get the current room index.

Returns: 0xFFFF if enterRoom() has never been called.

const Room& getRoom(uint16_t idx) const

Description:

Get a read-only reference to a room by index.

uint16_t roomCount() const

Description:

Number of rooms currently in the graph.

bool isValidIdx(uint16_t idx) const

Description:

Check if a room index is valid (idx < roomCount()).

uint8_t getConnections(uint16_t idx, int out[], uint8_t maxOut) const

Description:

Copy up to maxOut connection target indices into a caller-provided buffer.

Parameters:

• idx: Room index (no-op when out of range)
• out: Output buffer — must be non-null when maxOut > 0
• maxOut: Maximum number of connections to copy

Returns: Number of connections actually copied (≤ maxOut).

Truncation is documented, not an error: when the room has more connections than maxOut, only maxOut entries are written.