gRotate: Rotate geometries

Description Usage Arguments Value Examples

View source: R/geom_tools.r

Description

Rotate geoms by a certain angle about a center

Usage

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gRotate(geom, angle, about = c(0, 0), fid = NULL)

Arguments

geom

[geom]
Object of class geom.

angle

[numeric(1)]
the counter-clockwise angle by which geom shall be rotated.

about

[numeric(2)]
the point about which geom shall be rotated.

fid

[integerish(.)]
vector of features that should be rotated.

Value

Rotated geom.

Examples

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coords <- data.frame(x = c(30, 60, 60, 40, 10, 40, 20),
                     y = c(40, 40, 60, 70, 10, 20, 40),
                     fid = c(1, 1, 1, 1, 2, 2, 2))
window <- data.frame(x = c(0, 80),
                     y = c(0, 80))
aGeom <- geomPolygon(anchor = coords, window = window, show = TRUE)

rotatedGeom <- gRotate(geom = aGeom, angle = 90, about = c(40, 40))
visualise(geom = rotatedGeom)

# rotate single objects
rotatedTriangle <- gRotate(geom = aGeom, angle = -180, about = c(30, 40), fid = 2)
visualise(geom = rotatedTriangle, col = "goldenrod1")

# rotate different objects about different centers by different angles
rotateMore <- gRotate(geom = aGeom,
                      angle = list(90, -180),
                      about = list(c(40, 40), c(30, 40)))
visualise(geom = rotateMore, col = "deeppink")

EhrmannS/rasterTools documentation built on Feb. 4, 2019, 11:22 a.m.