Stretch geometric objects

Source: R/gt_stretch.R

Stretch geometric objects by a scale factor in x and y dimension.

gt_stretch(obj, x = NULL, y = NULL, fid = NULL, update = TRUE)

Arguments

obj

[geometric object(1)]
the object to stretch.
x

[numeric(1)]
the scale factor in x dimension.
y

[numeric(1)]
the scale factor in y dimension.
fid

[integerish(.)]
in case only a subset of features shall be stretched, specify that here.
update

[logical(1)]
whether or not to update the window slot after stretching.

Value

geom of the stretched obj.

See also

Other geometry tools: gt_filter(), gt_locate(), gt_pull(), gt_reflect(), gt_rotate(), gt_scale(), gt_skew(), gt_translate()

Examples

# stretch several features
visualise(gtGeoms$polygon, linewidth = 3)
newPoly <- gt_stretch(obj = gtGeoms$polygon, x = 0.5, y = 0.2,
                      update = FALSE)
visualise(geom = newPoly, linecol = "green", new = FALSE)


# stretch a single feature
visualise(gtGeoms$polygon, linewidth = 3)
newPoly <- gt_stretch(obj = gtGeoms$polygon, x = 0.5, fid = 2, update = FALSE)
visualise(geom = newPoly, linecol = "green", new = FALSE)


# stretch feature separately
visualise(gtGeoms$polygon, linewidth = 3)
newPoly <- gt_stretch(obj = gtGeoms$polygon,
                      x = c(0.2, 1),
                      y = c(1, 0.2),
                      update = FALSE)
visualise(geom = newPoly, linecol = "green", new = FALSE)