Expand Methods

Expanding a collection increases its size in one or more dimensions. Unlike Resize, Expand only allows increasing the size; attempting to reduce any dimension will result in an ArgumentOutOfRangeException.

Expanding Lists

You can expand a List2D, List3D, or List4D using the Expand method.

2D List Expansion

var list = new List2D<int>(2, 2); // 2x2 list
list.Expand(4, 4, -1);            // Expands to 4x4, filling new elements with -1

If we have a 2x2 list:

y\x	0	1
0	a	b
1	c	d

Calling Expand(3, 3, 'x') results in:

y\x	0	1	2
0	a	b	x
1	c	d	x
2	x	x	x

Default Value Factory

For reference types or when you need a new instance for each element, you can use a factory function:

var list = new List2D<MyClass>(2, 2);
list.Expand(4, 4, () => new MyClass());

Expanding Spaces

Expanding a Space2D or Space3D works similarly to lists, but it preserves the origin's relative position.

Expansion in Spaces

When you expand a space, the capacity of the underlying storage is increased, and the coordinate system is extended.

var space = new Space2D<int>(2, 2);
space.Expand(5, 5); // Increases the bounds of the space

Tip

Methods like Place have a resize parameter (true by default) that automatically calls Expand if the object being placed exceeds the current bounds.

var list = new List2D<int>(2, 2);
var other = new List2D<int>(3, 3);
list.Place(other, new Point2D(1, 1)); // list will automatically expand to 4x4