label_placer_simple: Generic label placement function

In isoband: Generate Isolines and Isobands from Regularly Spaced Elevation Grids

Generic label placement function

Description

The simple label placer processes separate isolines independently and places labels for each line using a placer function that does the actual placement work. This label placer is not meant to be used by end users, but rather facilitates the development of new label placers, such as label_placer_minmax().

Usage

label_placer_simple(lines, labels_data, placer_fun)

Arguments

lines	Isolines object for which labels should be placed.
labels_data	A data frame containing information about which labels should be placed.
placer_fun	A function that takes an individual isoline plus its associated break id as input and returns a data frame specifying label positions. The data frame should have three columns called x, y, and theta. x and y specify the label position, and theta specifies the label angle in radians. The data frame can have multiple rows, which results in the same label being placed in multiple locations.

isoband documentation built on Dec. 28, 2022, 2:38 a.m.