R: Geometric Transformations

GeomTrans {DescTools} | R Documentation

## Geometric Transformations

### Description

This function transforms geometric structures by translating, scaling and/or rotatin them.

### Usage

    GeomTrans(x, y = NULL, trans = 0, scale = 1, theta = 0)

### Arguments

`x, y` | vectors containing the coordinates of the vertices of the polygon , which has to be transformed. The coordinates can be passed in a plotting structure (a list with x and y components), a two-column matrix, .... See `xy.coords`.
`trans` | a vector of two values for the translation in x-, resp. y-direction. If only one value is supplied it will be recycled.
`scale` | a vector of two values for the scaling factor in x-, resp. y-direction. If only one value is supplied it will be recycled.
`theta` | angle of the rotation in radians starting from 3 o'clock counterclockwise.

### Value

The function invisibly returns a list of the coordinates for the transformed shape(s).

### Author(s)

Andri Signorell <andri@signorell.net>

### See Also

`polygon`, `DrawRegPolygon`, `DrawEllipse`, `DrawArc`

### Examples

    # let's have a triangle
    Canvas(main="Rotation")
    x <- DrawRegPolygon(nv=3)[[1]]

    xt <- GeomTrans(x, trans=c(1, 3), scale=c(2, 2), theta=pi/4)
    polygon(xt)

[Package DescTools version 0.99.36 Index]