MapHelper

MapHelper provides utility methods for tile-based game development, including coordinate conversion, spatial queries, and pathfinding helpers.

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Overview

Feature	Description
Coordinate Conversion	Tile-to-world and world-to-tile conversion
Index Conversion	1D to 2D index conversion and vice versa
Spatial Queries	Circle, ring, line, rectangle, and edge queries
Distance Calculations	Manhattan and Chebyshev distance
Adjacency	Check if units are adjacent with optional diagonals
Flood Fill	Find all connected walkable tiles

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Coordinate Conversion

MapToWorld

Converts a tile-based grid location into world-space coordinates.

// Tile (5, 3) with 32px tiles becomes world position (160, 96)
Vect2 worldPos = MapHelper.MapToWorld(new Vect2(5, 3), 32);

WorldToMap

Converts a world-space position into map grid coordinates.

// World position (160, 96) with 32px tiles becomes tile (5, 3)
Vect2 tilePos = MapHelper.WorldToMap(new Vect2(160, 96), 32);

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Index Conversion

To2D

Converts a 1-dimensional tile index into a 2D coordinate.

Vect2 tile = MapHelper.To2D(45, 10);  // Returns (5, 4)

To1D

Converts a 2D tile coordinate into a 1-dimensional index.

int index = MapHelper.To1D(new Vect2(5, 4), 10);  // Returns 45

WorldToIndex

Converts a world-space position into a 1D tile index.

int index = MapHelper.WorldToIndex(new Vect2(160, 96), 32, 10);  // Returns 45

IndexToWorld

Converts a 1D tile index into a world-space position (top-left corner of the tile).

Vect2 worldPos = MapHelper.IndexToWorld(45, 32, 10);  // Returns (160, 96)

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Spatial Queries

ToMap

Converts a world-space size into a list of tile coordinates covering the area.

var tiles = MapHelper.ToMap(
    new Vect2(64, 64),  // Size in pixels
    new Vect2(0, 0),    // Starting tile
    32                  // Tile size
);
// Returns tiles (0,0), (1,0), (0,1), (1,1)

ToCircle

Returns all tile coordinates within a circular radius of a center point.

var tiles = MapHelper.ToCircle(new Vect2(5, 5), 3);
// Returns all tiles within 3 tiles of (5, 5)

ToRing

Returns all tile coordinates within a circular ring (donut shape).

var tiles = MapHelper.ToRing(new Vect2(5, 5), 2, 5);
// Returns tiles between 2 and 5 tiles from center

ToLine

Returns all tile coordinates along a line between two tile positions using Bresenham's algorithm.

var tiles = MapHelper.ToLine(new Vect2(0, 0), new Vect2(5, 3));
// Returns all tiles along the line from (0,0) to (5,3)

ToEdge

Returns all tiles on the border of a rectangular area.

var tiles = MapHelper.ToEdge(new Vect2(0, 0), 5, 4);
// Returns all tiles on the border of a 5x4 rectangle

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Distance Calculations

ManhattanDistance

Calculates the Manhattan distance between two tile coordinates.

int distance = MapHelper.ManhattanDistance(
    new Vect2(0, 0),
    new Vect2(3, 4)
);  // Returns 7 (3 + 4)

ChebyshevDistance

Calculates the Chebyshev distance between two tile coordinates.

int distance = MapHelper.ChebyshevDistance(
    new Vect2(0, 0),
    new Vect2(3, 4)
);  // Returns 4 (max of 3 and 4)

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Bounds Checking

IsInBounds

Determines whether a tile coordinate is within the bounds of a map.

bool inBounds = MapHelper.IsInBounds(
    new Vect2(5, 3),
    10,  // mapWidth
    10   // mapHeight
);  // Returns true

bool outOfBounds = MapHelper.IsInBounds(
    new Vect2(10, 3),
    10,  // mapWidth
    10   // mapHeight
);  // Returns false

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Adjacency

IsUnitAround

Determines whether a unit is adjacent to another unit on a tile grid.

// Check orthogonal adjacency only
bool adjacent = MapHelper.IsUnitAround(
    new Vect2(5, 5),
    new Vect2(5, 6),
    false  // exclude corners
);  // Returns true (down)

// Check orthogonal and diagonal adjacency
bool adjacent = MapHelper.IsUnitAround(
    new Vect2(5, 5),
    new Vect2(6, 6),
    true  // include corners
);  // Returns true (diagonal)

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Flood Fill

FloodFill

Performs a flood fill starting from a tile coordinate.

// Define walkable tiles
Func<Vect2, bool> isWalkable = (tile) =>
{
    // Check if the tile is walkable
    return !MapManager.HasCollided(tile);
};

// Find all connected walkable tiles from start
var walkableTiles = MapHelper.FloodFill(
    new Vect2(0, 0),
    isWalkable
);

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Examples

Player Movement with World to Tile

public void UpdatePlayerPosition(Vect2 worldPosition)
{
    // Convert world position to tile
    var tile = MapHelper.WorldToMap(worldPosition, Globals.TileSize);
    
    // Check if the tile is walkable
    if (!MapManager.HasCollided(tile))
    {
        player.Position = MapHelper.MapToWorld(tile, Globals.TileSize);
    }
}

Finding Nearby Enemies

public List<Enemy> GetNearbyEnemies(Vect2 playerTile, int radius)
{
    var nearbyTiles = MapHelper.ToCircle(playerTile, radius);
    var enemies = new List<Enemy>();
    
    foreach (var tile in nearbyTiles)
    {
        enemies.AddRange(_enemyMap[tile]);
    }
    
    return enemies;
}

Drawing a Grid Border

public void DrawMapBorder()
{
    var borderTiles = MapHelper.ToEdge(
        Vect2.Zero,
        (int)Level.GridSize.X,
        (int)Level.GridSize.Y
    );
    
    foreach (var tile in borderTiles)
    {
        // Draw border tile
        DrawTile(tile, Color.White);
    }
}

Enemy Vision Cone

public bool CanSeePlayer(Vect2 enemyTile, Vect2 playerTile, int visionRange)
{
    // Check if player is within vision range
    if (ManhattanDistance(enemyTile, playerTile) > visionRange)
        return false;
    
    // Check line of sight
    var lineTiles = MapHelper.ToLine(enemyTile, playerTile);
    foreach (var tile in lineTiles)
    {
        if (MapManager.HasCollided(tile))
            return false;
    }
    
    return true;
}

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Summary

Method	Description
MapToWorld	Converts tile to world position
WorldToMap	Converts world position to tile
To2D	Converts 1D index to 2D tile
To1D	Converts 2D tile to 1D index
WorldToIndex	Converts world position to 1D index
IndexToWorld	Converts 1D index to world position
ToMap	Converts world area to tiles
ToCircle	Gets tiles within a circle
ToRing	Gets tiles within a ring
ToLine	Gets tiles along a line
ToEdge	Gets tiles on a rectangle border
IsInBounds	Checks if tile is in bounds
ManhattanDistance	Calculates Manhattan distance
ChebyshevDistance	Calculates Chebyshev distance
IsUnitAround	Checks adjacency
FloodFill	Finds connected walkable tiles

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