Struct TriCoord

Immutable coordinate for a cell in a triangular grid, expressed in three-axis lane coordinates (A, B, C).

Implements

IEquatable<TriCoord>

Inherited Members

object.Equals(object, object)

object.GetType()

object.ReferenceEquals(object, object)

Namespace: Scylla.Core.Structures

Assembly: ScyllaCore.dll

Syntax

public readonly struct TriCoord : IEquatable<TriCoord>

Remarks

A triangular tiling can be described by three families of parallel lines - the A, B, and C lanes - each at 60-degree angles to each other. Each triangle is uniquely identified by which lane-strips it falls inside:

• Downward triangle (A + B + C = 1): the flat edge faces upward; check with IsDownward.
• Upward triangle (A + B + C = 2): the apex points upward; check with IsUpward.

The distance metric for this coordinate system is the sum of absolute component differences: |ΔA| + |ΔB| + |ΔC|. Use Distance(TriCoord, TriCoord) or DistanceTo(TriCoord) to compute it.

To retrieve the three edge-sharing neighbor cells, use GetEdgeNeighbors(TriCoord, Span<TriCoord>). For world-space conversions, use a TriGridLayout.

Constructors

TriCoord(int, int, int)

Creates a new triangle grid coordinate with the specified lane values.

Declaration

public TriCoord(int a, int b, int c)

Parameters

Type	Name	Description
int	a	The A lane value for the new coordinate.
int	b	The B lane value for the new coordinate.
int	c	The C lane value for the new coordinate. For a downward triangle, a + b + c must equal 1; for an upward triangle, 2.

Fields

A

The A lane value. Represents which strip along the A-axis family of lines this triangle occupies.

Declaration

public readonly int A

Field Value

Type	Description
int

B

The B lane value. Represents which strip along the B-axis family of lines this triangle occupies.

Declaration

public readonly int B

Field Value

Type	Description
int

C

The C lane value. Represents which strip along the C-axis family of lines this triangle occupies.

Declaration

public readonly int C

Field Value

Type	Description
int

Properties

IsDownward

Gets a value indicating whether this triangle points downward (A + B + C = 1).

Declaration

public bool IsDownward { get; }

Property Value

Type	Description
bool	true when the sum of all lane values equals 1, identifying a downward-pointing triangle (flat edge facing up); false otherwise.

IsUpward

Gets a value indicating whether this triangle points upward (A + B + C = 2).

Declaration

public bool IsUpward { get; }

Property Value

Type	Description
bool	true when the sum of all lane values equals 2, identifying an upward-pointing triangle; false otherwise.

Methods

Distance(TriCoord, TriCoord)

Computes the triangular-grid distance between two coordinates as the sum of absolute component differences: |ΔA| + |ΔB| + |ΔC|.

Declaration

public static int Distance(TriCoord a, TriCoord b)

Parameters

Type	Name	Description
TriCoord	a	The first triangle coordinate.
TriCoord	b	The second triangle coordinate.

Returns

Type	Description
int	A non-negative integer representing the distance between a and b in triangle steps. Returns 0 when the coordinates are equal.

Remarks

This metric counts the minimum number of edge-crossing steps required to travel from one triangle to another, which equals one step per lane boundary crossed.

DistanceTo(TriCoord)

Computes the triangular-grid distance from this coordinate to another.

Declaration

public int DistanceTo(TriCoord other)

Parameters

Type	Name	Description
TriCoord	other	The target triangle coordinate.

Returns

Type	Description
int	A non-negative integer equal to |A - other.A| + |B - other.B| + |C - other.C|. Returns 0 when other equals this coordinate.

See Also

Distance(TriCoord, TriCoord)

Equals(TriCoord)

Determines whether this coordinate equals another coordinate.

Declaration

public bool Equals(TriCoord other)

Parameters

Type	Name	Description
TriCoord	other	The coordinate to compare with.

Returns

Type	Description
bool	True if all three lane values are equal.

Equals(object)

Determines whether this coordinate equals another object.

Declaration

public override bool Equals(object obj)

Parameters

Type	Name	Description
object	obj	The object to compare with.

Returns

Type	Description
bool	True if the object is a TriCoord with equal values.

Overrides

ValueType.Equals(object)

GetEdgeNeighbors(TriCoord, Span<TriCoord>)

Writes the three edge-sharing neighbors of the specified triangle into the provided buffer without allocating.

Declaration

public static int GetEdgeNeighbors(TriCoord coord, Span<TriCoord> buffer)

Parameters

Type	Name	Description
TriCoord	coord	The triangle coordinate whose neighbors are requested.
Span<TriCoord>	buffer	A span of at least 3 elements to receive the neighbor coordinates. If the span is smaller than 3 no neighbors are written and 0 is returned.

Returns

Type	Description
int	The number of neighbors written into buffer - always 3 when buffer has at least 3 elements, or 0 if the buffer is too small.

Remarks

Every triangle in the tiling has exactly three edge-sharing neighbors, one along each lane axis:

• Upward triangle (A + B + C = 2): neighbors are obtained by decrementing each component by 1 individually - (A-1, B, C), (A, B-1, C), (A, B, C-1).
• Downward triangle (A + B + C = 1): neighbors are obtained by incrementing each component by 1 individually - (A+1, B, C), (A, B+1, C), (A, B, C+1).

This method does not clip to any grid bounds. Use GetNeighborsNonAlloc(TriCoord, Span<TriCoord>) or GetNeighborsNonAlloc(TriCoord, Span<TriCoord>) to filter results to in-bounds or populated cells.

GetHashCode()

Returns a hash code for this coordinate.

Declaration

public override int GetHashCode()

Returns

Type	Description
int	A hash code based on A, B, and C.

Overrides

ValueType.GetHashCode()

ToString()

Returns a human-readable string representation of this coordinate.

Declaration

public override string ToString()

Returns

Type	Description
string	A string in the format (A, B, C), for example (1, 1, -1).

Overrides

ValueType.ToString()

Operators

operator +(TriCoord, TriCoord)

Returns a new coordinate whose lane values are the component-wise sum of a and b.

Declaration

public static TriCoord operator +(TriCoord a, TriCoord b)

Parameters

Type	Name	Description
TriCoord	a	The first coordinate.
TriCoord	b	The second coordinate.

Returns

Type	Description
TriCoord	A new TriCoord equal to (a.A+b.A, a.B+b.B, a.C+b.C).

operator ==(TriCoord, TriCoord)

Returns true when left and right have identical A, B, and C values.

Declaration

public static bool operator ==(TriCoord left, TriCoord right)

Parameters

Type	Name	Description
TriCoord	left	The left operand.
TriCoord	right	The right operand.

Returns

Type	Description
bool	true if both coordinates are equal; otherwise false.

operator !=(TriCoord, TriCoord)

Returns true when left and right differ in at least one lane value.

Declaration

public static bool operator !=(TriCoord left, TriCoord right)

Parameters

Type	Name	Description
TriCoord	left	The left operand.
TriCoord	right	The right operand.

Returns

Type	Description
bool	true if the coordinates are not equal; otherwise false.

operator *(TriCoord, int)

Returns a new coordinate whose lane values are each multiplied by scalar.

Declaration

public static TriCoord operator *(TriCoord coord, int scalar)

Parameters

Type	Name	Description
TriCoord	coord	The coordinate to scale.
int	scalar	The integer scalar.

Returns

Type	Description
TriCoord	A new TriCoord equal to (coord.Ascalar, coord.Bscalar, coord.C*scalar).

operator *(int, TriCoord)

Returns a new coordinate whose lane values are each multiplied by scalar (scalar-first overload).

Declaration

public static TriCoord operator *(int scalar, TriCoord coord)

Parameters

Type	Name	Description
int	scalar	The integer scalar.
TriCoord	coord	The coordinate to scale.

Returns

Type	Description
TriCoord	A new TriCoord equal to (scalarcoord.A, scalarcoord.B, scalar*coord.C).

operator -(TriCoord, TriCoord)

Returns a new coordinate whose lane values are the component-wise difference of a minus b.

Declaration

public static TriCoord operator -(TriCoord a, TriCoord b)

Parameters

Type	Name	Description
TriCoord	a	The minuend coordinate.
TriCoord	b	The subtrahend coordinate.

Returns

Type	Description
TriCoord	A new TriCoord equal to (a.A-b.A, a.B-b.B, a.C-b.C).

operator -(TriCoord)

Returns a new coordinate with all lane values negated.

Declaration

public static TriCoord operator -(TriCoord coord)

Parameters

Type	Name	Description
TriCoord	coord	The coordinate to negate.

Returns

Type	Description
TriCoord	A new TriCoord equal to (-coord.A, -coord.B, -coord.C).

Implements

IEquatable<T>

See Also

TriEdgeCoord

TriCornerCoord

TriGridLayout

ScyllaTriGrid<TCell>

ScyllaSparseTriGrid<TCell>