commit 28bad3583fbca7ae144268575f026363fab34817 (tree)
parent b800fd308c773970127ad5d9bbb1e9fd2df6c545
Author: Motiejus Jakštys <motiejus@uber.com>
Date: Mon, 1 Mar 2021 10:36:55 +0200
more notes
Diffstat:
1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/IV/notes.txt b/IV/notes.txt
@@ -18,19 +18,22 @@ after a few bends have been skipped. E.g. ends of A<->B cross the line, but
/ | | |___,---,___/A |
/ | \_________________|
\ |
- \ |
- / /
- ----/ /
- / ,____/
-/ B|
+ \ | \ |
+ / / B\ | _ __
+ ----/ / | | / \ / \
+ / ,____/ | |___/ \___/A |
+/ B| \_________________|
|
+
+
If a bend with 180+ deg inflection 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. In other words, can be very
computationally expensive.
-This may be slightly computationally simplified: if other bend's
-endpoints (A' and B') are in different sub-planes as divided by AB, then the
-crossing exists, and more expensive st_split can be used.
+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
+intersects with AB. Some intersections may be missed (see the example), but
+they will be eliminated by just joining A and B.
