49 lines
1.6 KiB
Plaintext
49 lines
1.6 KiB
Plaintext
poly2d - Yet another 2D polygon library
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Why do we need another 2D polygon library, if there are already CGAL,
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Boost, Clipper, GPC, ... ?
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All the above are either written in a weird language, are under a
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non-Free license, or simply don't provide the feature set we need
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here. poly2d is written in C, doesn't depend on non-standard
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libraries, and is licensed under the GPL (will change to LGPL).
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poly2d serves itself liberally from code already in cameo but
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provides a simpler and cleaner interface. The first objective is
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to provide the tools to replace the (badly broken) area filling
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operation in cameo. Later, poly2d could replace more parts of
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cameo.
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poly2d puts more emphasis on simplicity than on performance. Some
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functions expect closed polygons that don't self-intersect. For now,
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it doesn't matter whether polygons are clockwise or counter-clockwise.
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The table below shows the capabilities
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Open Min. vertices
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| Concave
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| | Self-intersect
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Y Y Y 0 p2d_contains_poly(b), p2d_copy, p2d_free, p2d_free_all,
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p2d_is_closed, p2d_no_intersect, p2d_reverse,
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p2d_vertices, p2d_write_gnuplot, p2d_write_gnuplot_all
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Y Y Y 1 p2d_read_gnuplot
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- Y Y 0 p2d_simplify
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- Y - 3 p2d_is_cw
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- Y - 3 p2d_contains_point, p2d_contains_poly (a),
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- Y - 3 p2d_area*, p2d_offset*
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Not yet implemented:
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- p2d_simplify (low priority - the offsetting from CGAL already covers
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the main use case)
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Not yet specified:
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- subtraction (do we actually need it ?)
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Other:
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- transform CGAL's idea of outer polygons into something we can use
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- check for memory leaks
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Prerequisite:
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libcgal-dev
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