Feature #2916: Add knife align up function to locate knife at beginning cut precisely

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Russ4262
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Re: Feature #2916: Add knife align up function to locate knife at beginning cut precisely

Post by Russ4262 »

@Sliptonic,
I think the op/dress-up needs a specific lead-in maneuver added to it.

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sliptonic
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Re: Feature #2916: Add knife align up function to locate knife at beginning cut precisely

Post by sliptonic »

Russ4262 wrote: Tue Jan 07, 2020 12:47 am I think the op/dress-up needs a specific lead-in maneuver added to it.
You think the dragknife dressup needs a leadin/out that's unique to dragknife?

A lead in would need to pick a new start point offset a certain distance from the actual starting location. The trick is how to I find a safe starting location that doesn't interfer with any other part of the model. My first thought was to pick a point outside the boundbox of the operation and directly opposite the current starting point. But I don't think this will work because I can't guarantee the start location is near the edge of the boundbox. It might be fully surrounded by other parts of the cut.

One possibility is to not pick the point but let the user select one. If that's the case, why is it unique to dragknife and not a general purpose lead in?
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Re: Feature #2916: Add knife align up function to locate knife at beginning cut precisely

Post by chrisb »

sliptonic wrote: Tue Jan 07, 2020 4:27 am One possibility is to not pick the point but let the user select one. If that's the case, why is it unique to dragknife and not a general purpose lead in?
I like that, for all operations. It would be very flexible if the x/y coordinates of the start vertex were available to expressions.
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sliptonic
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Re: Feature #2916: Add knife align up function to locate knife at beginning cut precisely

Post by sliptonic »

chrisb wrote: Tue Jan 07, 2020 2:49 pm
sliptonic wrote: Tue Jan 07, 2020 4:27 am One possibility is to not pick the point but let the user select one. If that's the case, why is it unique to dragknife and not a general purpose lead in?
I like that, for all operations. It would be very flexible if the x/y coordinates of the start vertex were available to expressions.
They're easy enough to find and it would be possible to expose them to expressions but it won't be one per operation. That's the problem with a manually created startpoint too. Operations can have many start points if the cutter lifts and re-positions.
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Re: Feature #2916: Add knife align up function to locate knife at beginning cut precisely

Post by mlampert »

sliptonic wrote: Tue Jan 07, 2020 4:36 pm
chrisb wrote: Tue Jan 07, 2020 2:49 pm
sliptonic wrote: Tue Jan 07, 2020 4:27 am One possibility is to not pick the point but let the user select one. If that's the case, why is it unique to dragknife and not a general purpose lead in?
I like that, for all operations. It would be very flexible if the x/y coordinates of the start vertex were available to expressions.
They're easy enough to find and it would be possible to expose them to expressions but it won't be one per operation. That's the problem with a manually created startpoint too. Operations can have many start points if the cutter lifts and re-positions.
I'm afraid it might not be that simple for the dragknife, the start point needs to be "tangential" to the first move otherwise it doesn't do what it's supposed to do. This is specific to the dragknife though.
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Re: Feature #2916: Add knife align up function to locate knife at beginning cut precisely

Post by chrisb »

Dragknife-dressup on a Contour or Profile op is stunning. The knife is lifted at each corner:
Snip macro screenshot-81ea87.png
Snip macro screenshot-81ea87.png (1.7 KiB) Viewed 1148 times

Profile+LeadIn+Dragknife looks rather promising:
Snip macro screenshot-43da18.png
Snip macro screenshot-43da18.png (3.27 KiB) Viewed 1148 times

Just for amusement: Profile+Dragknife+Leadin is really funny
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Snip macro screenshot-b73bcd.png
Snip macro screenshot-b73bcd.png (6.97 KiB) Viewed 1148 times
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Kunda1
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Re: Feature #2916: Add knife align up function to locate knife at beginning cut precisely

Post by Kunda1 »

Can anyone summarize what the decision with this feature is?
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Re: Feature #2916: Add knife align up function to locate knife at beginning cut precisely

Post by sliptonic »

There's consensus that something is needed but no ideas about how to achieve it. For a simple single-wire profile, it's pretty easy. Let the user pick a point to start at. That doesn't work in all cases because a profile might have many wires where the tool is lifted between. What's needed is an algorithm that will consistently pick a safe starting point regardless of the profile.
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Re: Feature #2916: Add knife align up function to locate knife at beginning cut precisely

Post by Kunda1 »

Thanks @sliptonic!
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