37 lines
1.4 KiB
Plaintext
37 lines
1.4 KiB
Plaintext
Definition of a bend: ends of the line should always be bends, otherwise not
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all line vertices are covered by bends (definition elsewhere).
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Gentle inflection at the end of the bend: the article does not specify how many
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vertices should be included when calculating the end-of-bend inflection. We
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chose the iterative approach -- as long as the angle is "right" and the
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distance is (greedily) decreasing, keep going.
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Self-line crossing when cutting a bend: the self-line-crossing may happen
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after a few bends have been skipped. E.g. ends of A<->B cross the line, but
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"swallow" a few more in between:
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,______
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/ \
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|___A | \ |
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\ | B\ | __
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\ | | | / \
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/ | | |___,---,___/A |
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/ | \_________________|
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\ |
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\ |
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/ /
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----/ /
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/ ,____/
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/ B|
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If a bend with 180+ deg inflection is found, its line between inflection angles
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(AB in our examples) must be crossed with all the other bends to detect a
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possible line-crossing. This is O(N*M), where N is the total number of line
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segments, and M is the number of qualifying bends. In other words, can be very
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computationally expensive.
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This may be slightly computationally simplified: if other bend's
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endpoints (A' and B') are in different sub-planes as divided by AB, then the
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crossing exists, and more expensive st_split can be used.
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