crop_burn: Crop a controlledburn result to a target extent

In controlledburn: Sparse Geometry Rasterization with Exact Coverage Fractions

Crop a controlledburn result to a target extent

Description

Filters and clips the sparse tables (runs, edges, lines, points) to a sub-window defined by a target extent. Returns a new controlledburn object with offset row/col indices and snapped extent. No dense allocation — just data frame filtering.

Usage

crop_burn(x, target)

Arguments

x	A controlledburn object returned by burn().
target	numeric vector c(xmin, xmax, ymin, ymax) defining the target window. Snapped outward to cell boundaries.

Value

A controlledburn object covering only the target window, with row/col indices re-based to 1.

Examples

if (requireNamespace("geos", quietly = TRUE)) {
  library(geos)
  poly <- as_geos_geometry("POLYGON ((1 1, 9 1, 9 9, 1 9, 1 1))")
  r <- burn(poly, extent = c(0, 10, 0, 10), dimension = c(100L, 100L))
  sub <- crop_burn(r, target = c(2, 5, 3, 7))
  sub
}

controlledburn documentation built on Oct. 28, 2026, 5:12 p.m.