BezierCurve:insertControlPoint() indexing last doesn't work properly
Posted: Sat May 11, 2019 6:07 am
From the wiki...
...should yield the following result.
Since each point is supposed to be inserted at the last index, we expect the points to be in order as shown.
Here's what happens instead...
Attempting to insert a point at the last index (-1) actually inserts it at the second last index.
Okay, so we think to try inserting at index 0 maybe?
Unfortunately that doesn't work....
This gets treated as if you were inserting at index 1, which keeps your points in line but reverses their order since you're constantly pushing the whole list forward.
Additionally: the wiki's description, "points from i onwards are pushed back by 1" should actually say that the points are pushed forward, at least that's the intended result, right?
If I'm reading this correctly, the following code...BezierCurve:insertControlPoint
Insert control point as the new i-th control point. Existing control points from i onwards are pushed back by 1. Indices start with 1. Negative indices wrap around: -1 is the last control point, -2 the one before the last, etc.
Code: Select all
-- a simple curve with four points in a counter-clockwise motion
-- default index is -1 (last), but was included for clarity
curve:insertControlPoint(0, 0, -1) -- bottom left
curve:insertControlPoint(100, 0, -1) -- bottom right
curve:insertControlPoint(100, -100, -1) -- top right
curve:insertControlPoint(0, -100, -1) -- top left
print(curve:getControlPoint(1))
print(curve:getControlPoint(2))
print(curve:getControlPoint(3))
print(curve:getControlPoint(4))Code: Select all
0 0
100 0
100 100
0 100Here's what happens instead...
Code: Select all
100 0 -- (2nd)
100 100 -- (3rd)
0 100 -- (4th)
0 0 -- (1st)Okay, so we think to try inserting at index 0 maybe?
Unfortunately that doesn't work....
Code: Select all
0 100 -- (4th)
100 100 -- (3rd)
100 0 -- (2nd)
0 0 -- (1st)Additionally: the wiki's description, "points from i onwards are pushed back by 1" should actually say that the points are pushed forward, at least that's the intended result, right?