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bezier looping back to own point extrusion (by cmpxchg)
When a bezier loops back to its own point, it seems the extrusion is not handled correctly - is this considered a bug ? When using three points, and mapping third on itself, it works (see picture).
Sat Jan 20 2024, 13:56:38, download attachment bezier_feature.png
(no subject) (by Tom)
How did you get the sharp "teardrop" point? When I loop a Bezier back on itself the extrusion works, but it's smooth everywhere.
Sat Jan 20 2024, 14:15:32
(no subject) (by cmpxchg)
attached
Sat Jan 20 2024, 14:24:05, download attachment untitled.slvs
(no subject) (by Paul)
@cmpxchg This is a bug. I thought I had extruded that type of shape before, but it certainly doesn't work now so I may be mistaken. It fails when the sketch is just one bezier closed on itself like that too. I'm not sure where it's dropping the curve, but it does shade the closed area correctly prior to extrusion so it seems to be somewhere in the extrusion code. I'm super tempted to look at code right now, but I have to go somewhere ;-)

@Tom create a bezier by doing a left-click for the first point, and then a right-click for the end point (just make a straight line with it). This will give you a single bezier with 2 end points and 2 control points. Constrain the end points coincident and then move the 2 control points to shape the teardrop. It looks like the other hole he made was formed from two of these with their endpoints constrained together.

When you create a bezier with more than 2 mouse clicks, solvespace creates more than one 3rd order bezier curve and internally calculates where to put the control points to maintain continuity. Every line, curve, or circle in a sketch is composed of one or more beziers of degree 1, 2, or 3. Nothing in Solvespace actually goes higher in complexity than that. Circles are four 90 degree arcs (degree 2) for example.
Sat Jan 20 2024, 14:45:32
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