bomberman::sim Namespace Reference

Shared simulation primitives and constants used by both the client and the authoritative server. More...

Classes
struct	SpawnSlotCell
	One multiplayer spawn slot expressed in tile-cell coordinates. More...
struct	TilePos
	Tile-space Q8 position representing the CENTER of the entity. More...

Typedefs
using	TileMap = Tile[tileArrayHeight][tileArrayWidth]
	Read-only view of a runtime tile map (same layout as LevelScene::tiles).

Enumerations
enum class	PowerupType : uint8_t { SpeedBoost = 0 , Invincibility = 1 , BombRangeBoost = 2 , MaxBombsBoost = 3 }
	Supported temporary multiplayer powerup effects.

Functions
bool	isWalkable (const TileMap &map, int col, int row)
	Returns true if the given tile coordinate is passable.
bool	overlapsWall (const TileMap &map, int32_t xQ, int32_t yQ)
	Returns true if the AABB centered at (xQ, yQ) with half-extent kHitboxHalfQ overlaps any solid tile.
TilePos	stepMovement (TilePos pos, int8_t moveX, int8_t moveY, int32_t speedQ=kPlayerSpeedQ)
	Advances a position by one simulation tick given a directional input.
TilePos	stepMovementWithCollision (TilePos pos, int8_t moveX, int8_t moveY, const TileMap &map, int32_t speedQ=kPlayerSpeedQ)
	Advances a position by one tick with tile-map collision.
int	tileQToScreen (int32_t tileQ, int fieldPx, int scaledTile, int cameraPx)
	Converts a center tile-Q8 coordinate to the screen pixel at that center.
int	tileQToScreenTopLeft (int32_t tileQ, int fieldPx, int scaledTile, int cameraPx)
	Converts a center tile-Q8 coordinate to the screen top-left pixel for sprite rendering.
constexpr bool	isValidPowerupType (const uint8_t rawType)
	Returns true when a raw byte encodes one of the defined powerup types.
constexpr std::string_view	powerupTypeName (const PowerupType type)
	Returns a human-readable name for one powerup type.
constexpr std::size_t	powerupTypeIndex (const PowerupType type)
	Returns the stable array index used for per-type powerup stats.
constexpr uint32_t	powerupEffectDurationTicks (const PowerupType type)
	Returns the configured lifetime for one powerup effect.
constexpr SpawnSlotCell	spawnSlotCellForPlayerId (const uint8_t playerId)
	Returns the default spawn slot assigned to the given player id.
constexpr TilePos	spawnSlotTilePos (const SpawnSlotCell slot)
	Converts one tile-cell spawn slot to a center-position tile-Q8 coordinate.
constexpr TilePos	spawnTilePosForPlayerId (const uint8_t playerId)
	Returns the default center-position tile-Q8 spawn for the given player id.
void	generateTileMap (uint32_t seed, Tile outTiles[tileArrayHeight][tileArrayWidth])
	Populates outTiles with a procedurally generated tile map.

Variables
constexpr int32_t	kPlayerSpeedQ = static_cast<int32_t>(kPlayerSpeedTilesPerSecond * 256.0 / kTickRate + 0.5)
	Player movement speed in tile-Q8 units per simulation tick.
constexpr int32_t	kHitboxHalfQ = static_cast<int32_t>(kPlayerHitboxScale * 256.0f / 2.0f)
	Player hitbox half-extent in tile-Q8 units.
constexpr std::size_t	kPowerupTypeCount = 4
	Number of defined multiplayer powerup types.
constexpr std::array< PowerupType, 4 >	kRoundPowerupPlacements
	Stable per-round hidden placements seeded under random bricks.
constexpr uint8_t	kPowerupsPerRound = static_cast<uint8_t>(kRoundPowerupPlacements.size())
	Number of hidden powerups seeded into each round when enabled.
constexpr uint32_t	kDefaultPowerupDurationTicks = static_cast<uint32_t>(kTickRate) * 10u
	Default temporary powerup lifetime in simulation ticks.
constexpr uint32_t	kInvincibilityDurationTicks = kDefaultPowerupDurationTicks
	Invincibility lifetime in simulation ticks.
constexpr uint32_t	kSpeedBoostDurationTicks = kDefaultPowerupDurationTicks
	Speed boost lifetime in simulation ticks.
constexpr uint32_t	kBombRangeBoostDurationTicks = kDefaultPowerupDurationTicks
	Bomb-range boost lifetime in simulation ticks.
constexpr uint32_t	kMaxBombsBoostDurationTicks = kDefaultPowerupDurationTicks
	Max-bombs boost lifetime in simulation ticks.
constexpr double	kSpeedBoostTilesPerSecond = 5.5
	Future movement-speed target while the speed boost is active.
constexpr int32_t	kSpeedBoostPlayerSpeedQ
	Movement speed in tile-Q8 units per simulation tick while the speed boost is active.
constexpr uint8_t	kBombRangeBoostAmount = 1
	Additional blast radius applied to bombs placed during the range boost.
constexpr uint8_t	kBoostedMaxBombs = 2
	Bomb-cap target while the max-bombs boost is active.
constexpr uint32_t	kPowerupPlacementSeedSalt = 0x9E3779B9u
	Deterministic salt mixed into round placement RNG so repeated map seeds can still vary by round.
constexpr int16_t	kTickRate = 60
	Simulation tick rate in Hz.
constexpr uint8_t	kDefaultPlayerMaxBombs = 1
	Default number of simultaneously active bombs a player may own.
constexpr uint8_t	kDefaultPlayerBombRange = 1
	Default explosion radius in tiles for newly placed bombs.
constexpr uint32_t	kDefaultBombFuseTicks = static_cast<uint32_t>(kTickRate) * 3u / 2u
	Default authoritative bomb fuse in simulation ticks.
constexpr double	kPlayerSpeedTilesPerSecond = 4.0
	Player movement speed in tiles per second.
constexpr float	kPlayerHitboxScale = 0.5f
	Player hitbox size as a fraction of the tile size.
constexpr int32_t	kMaxFrameClampMs = 250
	Maximum milliseconds the fixed-step accumulator will simulate in one frame.
constexpr int32_t	kMaxStepsPerFrame = 8
	Maximum simulation steps taken within a single frame even if the accumulator exceeds the limit.
constexpr int32_t	kDefaultServerInputLeadTicks = 1
	Default server-side input lead in ticks for authoritative input scheduling.
constexpr int32_t	kDefaultServerSnapshotIntervalTicks = 1
	Default server snapshot interval in simulation ticks (1 = every tick / 60 Hz).
constexpr uint8_t	kLeftSpawnCol = 1
constexpr uint8_t	kRightSpawnCol = static_cast<uint8_t>(tileArrayWidth - 2)
constexpr uint8_t	kTopSpawnRow = 1
constexpr uint8_t	kBottomSpawnRow = 9
constexpr std::array< SpawnSlotCell, 4 >	kDefaultSpawnSlots
	Default player-id keyed spawn slots for the current arena layout.

Detailed Description

Shared simulation primitives and constants used by both the client and the authoritative server.

Function Documentation

generateTileMap()

void bomberman::sim::generateTileMap ( uint32_t  seed, Tile  outTiles[tileArrayHeight][tileArrayWidth]  )

inline

Populates outTiles with a procedurally generated tile map.

Parameters

seed	32-bit seed for the internal std::mt19937 PRNG.
outTiles	Output array, must be [tileArrayHeight][tileArrayWidth].

isWalkable()

bool bomberman::sim::isWalkable ( const TileMap &  map, int  col, int  row  )

inline

Returns true if the given tile coordinate is passable.

Stone and Brick are solid. Out-of-bounds is treated as solid (world boundary). Bomb is intentionally excluded here - bomb collision is a gameplay layer above sim.

stepMovement()

TilePos bomberman::sim::stepMovement ( TilePos  pos, int8_t  moveX, int8_t  moveY, int32_t  speedQ = kPlayerSpeedQ  )

inline

Advances a position by one simulation tick given a directional input.

Parameters

pos	Current position in tile-Q8.
moveX	Horizontal input in {-1, 0, 1}.
moveY	Vertical input in {-1, 0, 1}.
speedQ	Movement speed in tile-Q8 units per simulation tick.

stepMovementWithCollision()

TilePos bomberman::sim::stepMovementWithCollision ( TilePos  pos, int8_t  moveX, int8_t  moveY, const TileMap &  map, int32_t  speedQ = kPlayerSpeedQ  )

inline

Advances a position by one tick with tile-map collision.

Resolves X and Y axes independently so the player slides along walls instead of stopping dead when hitting a corner.

Parameters

pos	Current position in tile-Q8.
moveX	Horizontal input in {-1, 0, 1}.
moveY	Vertical input in {-1, 0, 1}.
map	Read-only tile map to check collision against.
speedQ	Movement speed in tile-Q8 units per simulation tick.

Returns

New position, guaranteed not to overlap any solid tile.

tileQToScreen()

int bomberman::sim::tileQToScreen ( int32_t  tileQ, int  fieldPx, int  scaledTile, int  cameraPx  )

inline

Converts a center tile-Q8 coordinate to the screen pixel at that center.

Use for debug overlays, hit indicators, etc.

Parameters

tileQ	Center position in tile-Q8 (entity center, not top-left).
fieldPx	Field origin in screen pixels.
scaledTile	Rendered tile size in pixels.
cameraPx	Camera offset in the same axis.

Returns

Screen pixel coordinate of the center.

tileQToScreenTopLeft()

int bomberman::sim::tileQToScreenTopLeft ( int32_t  tileQ, int  fieldPx, int  scaledTile, int  cameraPx  )

inline

Converts a center tile-Q8 coordinate to the screen top-left pixel for sprite rendering.

Sprites are positioned by their top-left corner. Given a center Q8 position, subtract half a tile (128 Q8 units = 0.5 tiles) before converting to get the top-left.

Parameters

tileQ	Center position in tile-Q8.
fieldPx	Field origin in screen pixels.
scaledTile	Rendered tile size in pixels.
cameraPx	Camera offset in the same axis.

Returns

Screen pixel coordinate of the sprite's top-left corner.

Variable Documentation

kDefaultSpawnSlots

constexpr std::array<SpawnSlotCell, 4> bomberman::sim::kDefaultSpawnSlots

constexpr

Initial value:

{{
        {kLeftSpawnCol, kTopSpawnRow},
        {kLeftSpawnCol, kBottomSpawnRow},
        {kRightSpawnCol, kTopSpawnRow},
        {kRightSpawnCol, kBottomSpawnRow},
    }}

Default player-id keyed spawn slots for the current arena layout.

These slots assume the existing rectangular border and stone-grid layout. Player ids beyond the four default seats currently wrap this corner table until a dedicated larger-match layout exists.

kPlayerHitboxScale

constexpr float bomberman::sim::kPlayerHitboxScale = 0.5f

constexpr

Player hitbox size as a fraction of the tile size.

Used by both the Q8 simulation and the SDL float collision system.

kRoundPowerupPlacements

constexpr std::array<PowerupType, 4> bomberman::sim::kRoundPowerupPlacements

constexpr

Initial value:

{{
        PowerupType::SpeedBoost,
        PowerupType::Invincibility,
        PowerupType::BombRangeBoost,
        PowerupType::MaxBombsBoost
    }}

Stable per-round hidden placements seeded under random bricks.

The array length defines how many powerups are hidden in each round. Repeating a type here increases its frequency without needing a separate weighted-RNG system.

kSpeedBoostPlayerSpeedQ

constexpr int32_t bomberman::sim::kSpeedBoostPlayerSpeedQ

constexpr

Initial value:

=
        static_cast<int32_t>(kSpeedBoostTilesPerSecond * 256.0 / kTickRate + 0.5)

Movement speed in tile-Q8 units per simulation tick while the speed boost is active.