GridCells

namespace Griff.Scenes;

public struct GridCells

The cells grid movers step between: a tilemap’s (its transform and tile size), or with none, world units centered on whole numbers. Rows count down either way, so a way (x right, y up) changes the cell by Offset(way), except on a hex map, where a way up or down goes to one of the two hexagons above or below (see Step).

Properties

IsHex

public bool IsHex { get; }

Whether its cells are a hex map’s hexagons.

IsIsometric

public bool IsIsometric { get; }

Whether its cells are an isometric map’s diamonds.

Map

public Tilemap? Map { get; init; }

ToLocal

public Matrix4x4 ToLocal { get; init; }

World

public Matrix4x4 World { get; init; }

Methods

AreNeighbours

public bool AreNeighbours(ValueTuple<int, int> a, ValueTuple<int, int> b)

Whether one cell is next to another (see Neighbours; on a square map, diagonally too).

CellAt

public ValueTuple<int, int> CellAt(Vector2 world)

The cell a world position is in.

Center

public Vector2 Center(ValueTuple<int, int> cell)

The world position of the middle of a cell.

Corners

public Vector2[] Corners(ValueTuple<int, int> cell, float scale)

A cell’s corners in the world, round its edge, shrunk to scale of it round its middle.

Deconstruct

public void Deconstruct(out Tilemap? Map, out Matrix4x4 World, out Matrix4x4 ToLocal)

Equals

public override bool Equals(object obj)

Equals

public bool Equals(GridCells other)

GetHashCode

public override int GetHashCode()

InWorld

public Vector2 InWorld(Vector2 way)

A way along the grid (x right, y up, a step’s worth) as it looks in the world: on an isometric map, (0, 1) is up to the right; on a hex map, (1, 1) is up to the right, to the hexagon half a tile across in the row above.

Neighbours

public ValueTuple<int, int>[] Neighbours(ValueTuple<int, int> cell, bool diagonal)

The cells next to one, as changes of cell (column, then row down): the six hexagons round it on a hex map, else the four beside it, or eight with the diagonals.

Of

public static GridCells Of(Tilemap? map)

The cells of map, or of world units when it is null or has no entity.

Offset

public static ValueTuple<int, int> Offset(ValueTuple<int, int> way)

The change of cell for a way (x right, y up): rows count down, so y is negated.

Resolve

public ValueTuple<int, int> Resolve(ValueTuple<int, int> cell, ValueTuple<int, int> way)

A way to step from a cell, as one of the grid’s own: on a hex map, straight up or down (0, ±1) is to the hexagon above or below on the right from an even row and on the left from an odd one, so holding it zigzags straight up the screen; every other way, and every way on other maps, is itself.

Shape

public IEnumerable<Matrix4x4> Shape(ValueTuple<int, int> cell, float scale)

What covers a cell’s shape in the world, shrunk to scale of it round its middle, as transforms of the unit quad: a square, a diamond or a hexagon (see CellShape).

Step

public ValueTuple<int, int> Step(ValueTuple<int, int> cell, ValueTuple<int, int> way)

The cell a step (x right, y up) from a cell goes into: on a hex map, the hexagon that way (see Resolve).

Steps

public int Steps(ValueTuple<int, int> a, ValueTuple<int, int> b, bool diagonal)

The fewest steps from one cell to another with nothing in the way: across and down, or with diagonal steps the longer of the two, and on a hex map the hexagons between them, whichever way they lie.

ToString

public override string ToString()

Toward

public Vector2 Toward(Vector2 offset, bool diagonal)

The way (x right, y up) to face to look along a world offset: on a hex map, the one of its six ways nearest the offset’s direction; on others, along the grid’s longer axis, or both if it steps diagonally. Down, for none.

WayBetween

public ValueTuple<int, int> WayBetween(ValueTuple<int, int> from, ValueTuple<int, int> to)

The way (x right, y up) a step from one cell into a neighbouring one goes: the other way from Step.

WayOf

public Vector2 WayOf(Vector2 offset)

A world offset as a way along the grid (x right, y up, in cells): the other way from InWorld.