Struct SquareCoord

Represents an integer coordinate in a square grid, addressed by column and row.

Implements
Inherited Members
Namespace: Scylla.Core.Structures
Assembly: ScyllaCore.dll
Syntax
public readonly struct SquareCoord : IEquatable<SquareCoord>
Remarks

SquareCoord is an immutable value type used to address cells within a square grid. The column (Col) increases to the right and the row (Row) increases downward, following screen-space conventions. The origin (0, 0) is located at the top-left corner of the grid.

The eight static direction vectors (Up, Down, Left, Right, UpLeft, UpRight, DownLeft, DownRight) can be added to any coordinate to step to an adjacent cell and are used by ScyllaSquareGrid<TCell> internally for neighbor queries.

To convert a SquareCoord to a world-space position, use GridToWorld(SquareCoord) or the equivalent method on a grid instance.

Constructors

SquareCoord(int, int)

Creates a new square grid coordinate at the specified column and row.

Declaration
public SquareCoord(int col, int row)
Parameters
Type Name Description
int col

The column index. Negative values address columns to the left of the origin.
int row

The row index. Negative values address rows above the origin.

Fields

Col

The column index. Increases to the right; may be negative for coordinates left of the origin.

Declaration
public readonly int Col
Field Value
Type Description
int

Down

Direction vector pointing down: (0, +1). Row increases by one.

Declaration
public static readonly SquareCoord Down
Field Value
Type Description
SquareCoord

DownLeft

Direction vector pointing diagonally down and left: (-1, +1).

Declaration
public static readonly SquareCoord DownLeft
Field Value
Type Description
SquareCoord

DownRight

Direction vector pointing diagonally down and right: (+1, +1).

Declaration
public static readonly SquareCoord DownRight
Field Value
Type Description
SquareCoord

Left

Direction vector pointing left: (-1, 0). Column decreases by one.

Declaration
public static readonly SquareCoord Left
Field Value
Type Description
SquareCoord

Right

Direction vector pointing right: (+1, 0). Column increases by one.

Declaration
public static readonly SquareCoord Right
Field Value
Type Description
SquareCoord

Row

The row index. Increases downward; may be negative for coordinates above the origin.

Declaration
public readonly int Row
Field Value
Type Description
int

Up

Direction vector pointing up: (0, -1). Row decreases by one.

Declaration
public static readonly SquareCoord Up
Field Value
Type Description
SquareCoord
Remarks

In screen-space row-major layout the row axis points downward, so moving "up" decrements the row index.

UpLeft

Direction vector pointing diagonally up and left: (-1, -1).

Declaration
public static readonly SquareCoord UpLeft
Field Value
Type Description
SquareCoord

UpRight

Direction vector pointing diagonally up and right: (+1, -1).

Declaration
public static readonly SquareCoord UpRight
Field Value
Type Description
SquareCoord

Zero

The origin coordinate (0, 0), located at the top-left of the grid.

Declaration
public static readonly SquareCoord Zero
Field Value
Type Description
SquareCoord

Methods

ChebyshevDistanceTo(SquareCoord)

Computes the Chebyshev distance from this coordinate to other.

Declaration
public int ChebyshevDistanceTo(SquareCoord other)
Parameters
Type Name Description
SquareCoord other

The target coordinate to measure distance to.
Returns
Type Description
int

The non-negative Chebyshev distance as an int. Returns 0 when other equals this coordinate.
Remarks

The Chebyshev distance is defined as max(|Col - other.Col|, |Row - other.Row|). It represents the minimum number of steps when diagonal moves cost the same as cardinal moves, and is the correct admissible heuristic for A* on grids that use Moore movement with uniform diagonal cost.

The subtraction is performed in 64-bit arithmetic to prevent integer overflow when coordinates span the full int range.

See Also

DistanceTo(SquareCoord, SquareDistanceMetric)

Computes the distance from this coordinate to other using the specified distance metric.

Declaration
public float DistanceTo(SquareCoord other, SquareDistanceMetric metric)
Parameters
Type Name Description
SquareCoord other

The target coordinate to measure distance to.
SquareDistanceMetric metric

The distance metric to apply.
Returns
Type Description
float

The distance as a float. Always non-negative; returns 0 when other equals this coordinate.
Remarks

Each metric is suited to a different movement model:

  • Manhattan - optimal heuristic for 4-connected (VonNeumann) grids.
  • Chebyshev - optimal heuristic for 8-connected grids where diagonal steps cost the same as cardinal steps.
  • Euclidean - straight-line geometric distance; underestimates on grids and should be used with care as an A* heuristic.
  • Octile - recommended A* heuristic for 8-way movement where diagonals cost sqrt(2): max(dx,dy) + (sqrt(2)-1)*min(dx,dy).

For integer results without floating-point overhead, prefer ManhattanDistanceTo(SquareCoord) or ChebyshevDistanceTo(SquareCoord).

Exceptions
Type Condition
ArgumentOutOfRangeException

Thrown when metric is not a recognised SquareDistanceMetric value.

Equals(SquareCoord)

Determines whether this coordinate is equal to other.

Declaration
public bool Equals(SquareCoord other)
Parameters
Type Name Description
SquareCoord other

The coordinate to compare with.
Returns
Type Description
bool

true if both Col and Row are equal; false otherwise.

Equals(object)

Determines whether this coordinate is equal to an arbitrary object.

Declaration
public override bool Equals(object obj)
Parameters
Type Name Description
object obj

The object to compare with. May be null.
Returns
Type Description
bool

true if obj is a SquareCoord with the same column and row values; false otherwise.
Overrides

GetHashCode()

Returns a hash code for this coordinate based on its column and row values.

Declaration
public override int GetHashCode()
Returns
Type Description
int

A hash code suitable for use in hash-based collections such as Dictionary<TKey, TValue>.
Overrides

ManhattanDistanceTo(SquareCoord)

Computes the Manhattan distance from this coordinate to other.

Declaration
public int ManhattanDistanceTo(SquareCoord other)
Parameters
Type Name Description
SquareCoord other

The target coordinate to measure distance to.
Returns
Type Description
int

The non-negative Manhattan distance as an int. Returns 0 when other equals this coordinate.
Remarks

The Manhattan distance is defined as |Col - other.Col| + |Row - other.Row|. It represents the minimum number of cardinal-direction (N/S/E/W) steps required to reach other on a grid with no obstacles, and is the correct admissible heuristic for A* pathfinding on grids that use VonNeumann movement.

The subtraction is performed in 64-bit arithmetic to prevent integer overflow when coordinates span the full int range.

See Also

ToString()

Returns a human-readable string representation of this coordinate.

Declaration
public override string ToString()
Returns
Type Description
string

A string in the format (Col, Row), e.g. (3, 7).
Overrides

Operators

operator +(SquareCoord, SquareCoord)

Adds two coordinates component-wise, producing a new coordinate offset from a by b.

Declaration
public static SquareCoord operator +(SquareCoord a, SquareCoord b)
Parameters
Type Name Description
SquareCoord a
SquareCoord b
Returns
Type Description
SquareCoord
Remarks

This operator is the primary mechanism for stepping in a direction. For example, coord + SquareCoord.Right moves one cell to the right.

operator ==(SquareCoord, SquareCoord)

Returns true if left and right have equal column and row values.

Declaration
public static bool operator ==(SquareCoord left, SquareCoord right)
Parameters
Type Name Description
SquareCoord left
SquareCoord right
Returns
Type Description
bool

operator !=(SquareCoord, SquareCoord)

Returns true if left and right differ in at least one component.

Declaration
public static bool operator !=(SquareCoord left, SquareCoord right)
Parameters
Type Name Description
SquareCoord left
SquareCoord right
Returns
Type Description
bool

operator *(SquareCoord, int)

Scales both components of coord by scalar. Useful for computing ring radii or region extents in grid units.

Declaration
public static SquareCoord operator *(SquareCoord coord, int scalar)
Parameters
Type Name Description
SquareCoord coord
int scalar
Returns
Type Description
SquareCoord

operator *(int, SquareCoord)

Scales both components of coord by scalar. Commutative overload of coord * scalar.

Declaration
public static SquareCoord operator *(int scalar, SquareCoord coord)
Parameters
Type Name Description
int scalar
SquareCoord coord
Returns
Type Description
SquareCoord

operator -(SquareCoord, SquareCoord)

Subtracts b from a component-wise, returning the displacement vector from b to a.

Declaration
public static SquareCoord operator -(SquareCoord a, SquareCoord b)
Parameters
Type Name Description
SquareCoord a
SquareCoord b
Returns
Type Description
SquareCoord

operator -(SquareCoord)

Returns a new coordinate with both components negated, effectively mirroring coord through the origin.

Declaration
public static SquareCoord operator -(SquareCoord coord)
Parameters
Type Name Description
SquareCoord coord
Returns
Type Description
SquareCoord

Implements

See Also