Feature idea: blended fusion

[DeepSOIC]

Hi!
Some may have noticed my evil plan for how to mentor jnxd in his GSoC. For those who didn't, it's here:
https://forum.freecadweb.org/viewtopic. ... 20#p168754
In point 1, I mentioned this feature.
And I think it's a good time to discuss it a bit, regardless if jnxd's proposal is accepted or not.

The idea: for operations that do fusions/cuts, it is possible to find edges where shapes being fused/cut intersect, and add fillets or chamfers there.

bleded-pad.png (461.32 KiB) Viewed 2067 times

This can take a number of forms: as a parameter in PartDesign operations, as a parameter in Part Booleans, or as an independent feature that can be applied to a fresh fusion.

Advantages:
* fillets are added to the places where they are usually wanted, quickly and conveniently.
* likewise, the fillets can be easily adjusted or removed altogether
* these fillets don't suffer lack need toponaming, they are inherently robust.
Disadvantages:
* deliberate violation of fillets-go-last principle, they may cause problems later on the way.
* overloading the incredibly simple UI of Pad/Pocket, and not so simple UI of partdesign revolution/loft/sweep

@jnxd: do you like the idea?
@everyone: Is it useful? UI ideas? Maybe a slightly different approach to achieve the same? better terminology?

[easyw-fc]

Hi!
The idea: for operations that do fusions/cuts, it is possible to find edges where shapes being fused/cut intersect, and add fillets or chamfers there.
bleded-pad.pngThis can take a number of forms: as a parameter in PartDesign operations, as a parameter in Part Booleans, or as an independent feature that can be applied to a fresh fusion.

Advantages:
* fillets are added to the places where they are usually wanted, quickly and conveniently.
* likewise, the fillets can be easily adjusted or removed altogether
* these fillets don't suffer lack need toponaming, they are inherently robust.
Disadvantages:
* deliberate violation of fillets-go-last principle, they may cause problems later on the way.
* overloading the incredibly simple UI of Pad/Pocket, and not so simple UI of partdesign revolution/loft/sweep

@jnxd: do you like the idea?
@everyone: Is it useful? UI ideas? Maybe a slightly different approach to achieve the same? better terminology?

+1 from my side!
very nice idea though!

[ickby]

I very much like it and think this is a good addition to the existing tools!

[sgrogan]

Wouldn't filleting the indicated edge "undercut" the vertical edge of the hexagon? Or would further blending (variable radius) be done?

[DeepSOIC]

Wouldn't filleting the indicated edge "undercut" the vertical edge of the hexagon?

I meant to indicate the fillet, not edge

[triplus]

Such features i guess are the next logical step (regardless of topology implications).

[Joyas]

deliberate violation of fillets-go-last principle, they may cause problems later on the way.

That principle is based on the toponaming problem, so I think that there is no problem for adding a fillet in the same operation.

[NormandC]

That principle is based on the toponaming problem

It's not, it's considered good practice for parametric modelling: apply chamfers and fillets last. It's not a good idea to base sketches on such features, that's true for any parametric CAD software.

Edit: this "resilient modelling strategy" recommends placing chamfers and fillets into a group labelled "quarantine" :
http://learnrms.com/27%2DQuarantine%2D09.html

@everyone: Is it useful?

To be honest I can't think of a case where it would have been useful to me. I guess that once it's available, I may find a use for it...

[Joyas]

That principle is based on the toponaming problem

It's not, it's considered good practice for parametric modelling: apply chamfers and fillets last. It's not a good idea to base sketches on such features, that's true for any parametric CAD software.

Edit: this "resilient modelling strategy" recommends placing chamfers and fillets into a group labelled "quarantine" :
http://learnrms.com/27%2DQuarantine%2D09.html

@everyone: Is it useful?

To be honest I can't think of a case where it would have been useful to me. I guess that once it's available, I may find a use for it...

Thanks, I did not know that.

[DeepSOIC]

(attention grabber quote)

Hi!
Are you interested in implementing this feature?
I remember in PM you asked for pointers on how to implement it.
Here's one:
https://www.freecadweb.org/wiki/Macro_Section