stud/IV/notes.txt

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Definition of a bend: ends of the line should always be bends, otherwise not
all line vertices are covered by bends (definition elsewhere).
Gentle inflection at the end of the bend: the article does not specify how many
vertices should be included when calculating the end-of-bend inflection. We
chose the iterative approach -- as long as the angle is "right" and the
distance is (greedily) decreasing, keep going.
Self-line crossing when cutting a bend: the self-line-crossing may happen
after a few bends have been skipped. E.g. ends of A<->B cross the line, but
"swallow" a few more in between:
,______
/ \
|___A | \ |
\ | B\ | __
\ | | | / \
/ | | |___,---,___/A |
/ | \_________________|
\ |
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\ | \ |
/ / B\ | _ __
----/ / | | / \ / \
/ ,____/ | |___/ \___/A |
/ B| \_________________|
|
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If a bend with 180+ deg sum of inflection angles is found, its line between
inflection angles (AB in our examples) must be crossed with all the other bends
to detect a possible line-crossing. This is O(N*M), where N is the total number
of line segments, and M is the number of qualifying bends. It is expensive.
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This may be simplified: if other bend's endpoints (A' and B') are in the same
sub-plane as divided by AB, then the bend can be skipped from checking if it
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intersects with AB. Some intersections may be missed (see the last example),
but they will be eliminated by joining A and B anyway.