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# Height and Width
## Introduction
`Polygons` can be any shape, so their width and height values cannot be explicitly set. Instead, a `Polygon's` width and height values are determined by their points.
## Width and Height from Points
A `Polygon's` effective width and height is determined by its points. The furthest-right point determines the polygon's width and the furthest down point determines the polygon's height.
For example, a square `Polygon` with the furthest points at 128,128 has a width of 128 and a height of 128.
A `Polygon's` height can be used to affect parents, siblings, and children depending on the other instances' `Width Units`, `Height Units`, and stacking values.
For example, we can add a rectangle as a child of a `ColoredRectangle` to see how its points affect the size of the polygon.
Polygons in a ColoredRectangle. The ColoredRectangle sizes itself according to the Polygon's width and height
We can see similar behavior if we place the Polygon in a stacking parent.
A `Polygon's` height and width are measured from a `Polygon's` top left corner to the furthest down right point. Points which have a negative value do not affect a `Polygon's` effective height, so moving points above or to the left of the origin will not affect the layout of any object which depends on the `Polygon's` size.
For example, if we move `Polygon` points in a stack up or to the left, this does not shift any of the Polygon's siblings.
Moving points so they have negative values does not affect the effective size of a Polygon
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