# Add additional nodes to lines or polygons

`densify.Rd`

Add additional nodes to lines or polygons. This can be useful to do prior to using `project`

such that the path does not change too much.

## Arguments

- x
SpatVector

- interval
positive number, specifying the desired minimum distance between nodes. The unit is meter for lonlat data, and in the linear unit of the crs for planar data

- equalize
logical. If

`TRUE`

, new nodes are spread at equal intervals between old nodes- flat
logical. If

`TRUE`

, the earth's curvature is ignored for lonlat data, and the distance unit is degrees, not meter

## Examples

```
v <- vect(rbind(c(-120,-20), c(-80,5), c(-40,-60), c(-120,-20)),
type="polygons", crs="+proj=longlat")
vd <- densify(v, 200000)
p <- project(v, "+proj=robin")
pd <- project(vd, "+proj=robin")
# good
plot(pd, col="gray", border="red", lwd=10)
points(pd, col="gray")
# bad
lines(p, col="blue", lwd=3)
points(p, col="blue", cex=2)
plot(p, col="blue", alpha=.1, add=TRUE)
legend("topright", c("good", "bad"), col=c("red", "blue"), lty=1, lwd=3)
## the other way around does not work
## unless the original data was truly planar (e.g. derived from a map)
x <- densify(p, 250000)
y <- project(x, "+proj=longlat")
# bad
plot(y)
# good
lines(vd, col="red")
```