This Python project expands on the capabilities of the rectangle-packer package primarily by adding efficient rotation checking (missing from the base package), the ability to maximize area usage of stock, and multi-sheet packing.
- Python 3.6+
- rectangle-packer
- matplotlib
from rectangle_packing import find_optimal_packing, plot_positions
# A list of 2-tuples representing the heights and widths of the rectangles to be packed
# Note: units are arbitrary, so just be consistent
sizes = [(4, 3), (4, 3), (2, 2), (2, 2), (3, 1), (8, 7), (7, 8), (2, 10), (1, 1)]
# The width and height of the rectangle that we are packing other rectangles into
stock_width = 20
stock_height = 10
# Find the optimal layout using all shapes, if possible
packed_sizes, positions = find_optimal_packing(sizes, stock_width, stock_height)
# If a valid layout is found, then plot the result
if packed_sizes is not None:
plot_positions(packed_sizes, positions, stock_width, stock_height)from rectangle_packing import find_max_usage, plot_positions
# A list of 2-tuples representing the heights and widths of the rectangles to be packed
# Note: units are arbitrary, so just be consistent
sizes = [(4, 3), (4, 3), (2, 2), (2, 2), (3, 1), (8, 7), (7, 8), (2, 10), (1, 1)]
stock_width = 15
stock_height = 10
# Try to use as much of the available area as possible, but don't guarantee
# that all shapes will be used
packed_sizes, positions = find_max_usage(sizes, stock_width, stock_height, None)
# If a valid layout is found, then plot the result
if packed_sizes is not None:
plot_positions(packed_sizes, positions, stock_width, stock_height)
Note: the more unique sizes there are the slower it will typically run. This is because fewer convenient assumptions can be made about unique shapes.
Ex:
- Fitting 500 of the same item onto 42 sheets: 0.1 sec
- Fitting 20 unique items onto 4 sheets: 5.9 sec
from rectangle_packing import multi_sheet_packing, multi_plot_positions
sizes = [(5, 30), (7, 10), (16, 16)] * 11
stock_width = 50
stock_height = 40
# Pack as many items onto one sheet as possible, then pack the remaining items
# onto another sheet. Repeat until all items are packed.
# Each sheet contains a pair of [sizes, positions] for the items that were
# packed onto that sheet.
# Assumes that each sheet has the same dimensions.
sheets = multi_sheet_packing(sizes, stock_width, stock_height)
if len(sheets) > 0:
multi_plot_positions(sheets, stock_width, stock_height)