Type: Package
Title: Rectangle Packing
Version: 1.0.0
Maintainer: Mike Cheng <mikefc@coolbutuseless.com>
URL: https://github.com/coolbutuseless/rectpacker
BugReports: https://github.com/coolbutuseless/rectpacker/issues
Description: Rectangle packing is a packing problem where rectangles are placed into a larger rectangular region (without overlapping) in order to maximise the use space. Rectangles are packed using the skyline heuristic as discussed in Lijun et al (2011) 'A Skyline-Based Heuristic for the 2D Rectangular Strip Packing Problem' <doi:10.1007/978-3-642-21827-9_29>. A function is also included for determining a good small-sized box for containing a given set of rectangles.
License: MIT + file LICENSE
Encoding: UTF-8
RoxygenNote: 7.3.2
Copyright: The included 'stb_rect_pack.h' header (v1.01) is Copyright (c) 2017 Sean Barrett and licensed under the MIT license. See COPYRIGHTS file for more details.
Suggests: testthat (≥ 3.0.0)
Config/testthat/edition: 3
NeedsCompilation: yes
Packaged: 2024-12-04 06:32:19 UTC; mike
Author: Mike Cheng [aut, cre, cph], Sean Barrett [aut, cph] (Author of included stb_rect_pack.h library)
Repository: CRAN
Date/Publication: 2024-12-05 19:00:02 UTC

Find the dimensions of a small box to store all the given rectangles

Description

This is a brute force search with a simple heuristic. Is not guaranteed to find the box with the minimum area, but simply a box that snugly fits the rectangles without too much wasted space.

Usage

calc_small_box(
  rect_widths,
  rect_heights,
  aspect_ratios = c(1.61803, 1/1.61803),
  verbosity = 0L
)

Arguments

rect_widths, rect_heights

widths and heights of the rectangles to pack.

aspect_ratios

Vector of box aspect ratios to be tested. Aspect ratio is defined here as width / height. Default: c(1.61803, 1/1.61803) i.e. golden ratio and its inverse.

verbosity

Level of debugging output. Default: 0 (no output)

Value

List with 2 elements: width and height of a small box which fits all the rectangles.

Examples

# Find a minimal box to fit 10 random rectangles.
# Search for boxes with aspect ratios in seq(0.5, 2, length.out = 20)
set.seed(2)
N <- 10
rect_widths  <- sample(N)
rect_heights <- sample(N)
box <- calc_small_box(rect_widths, rect_heights, 
                      aspect_ratios = seq(0.5, 2, length.out = 20))
box
rects <- pack_rects(box$width, box$height, rect_widths, rect_heights)
all(rects$packed)

Pack rectangles into a box using the skyline algorithm

Description

This implementation accepts only integer valued sizes and coordinates.

Usage

pack_rects(box_width, box_height, rect_widths, rect_heights)

Arguments

box_width, box_height

dimensions of the box into which the rectangles will be packed. Integer values.

rect_widths, rect_heights

widths and heights of the rectangles to pack.

Value

data.frame of packing information

idx

Integer index of rectangle in the input

w,h

Integer dimensions of each rectangle

packed

Logical: Was this rectangle packed into the box?

x,y

Integer coordinates of packing position of bottom-left of rectangle

Examples

# Pack 10 rectangles into a 25x25 box
# Note: All rectangles in the results have 'packed=TRUE' which
# means they all fit into the box
set.seed(1)
N <- 10
rect_widths  <- sample(N)
rect_heights <- sample(N)
pack_rects(box_width = 25, box_height = 25, rect_widths, rect_heights)