datum plane manual size

[Zolko]

Hello,

Datum Planes (PartDesign::Plane) can have either automatic dimensions, or manually set dimensions, for the 3D viewer. In this latter case, there are 2 properties that set this dimension: Length and Width. When setting the dimension manually, the plane's visual representation becomes a rectangle, with 1 corner always the 0,0 origin of the plane. Thus, when drawing a circle for example, the circle is outside the rectangle.

It is possible to manually set the datum plane's size and position by dragging its edges in other CAD programs. While I don't ask for such feature, it would be better that the datum plane is centered around it's origin, meaning that it should extend from -Length/2 to Length/2, and from -Width/2 to Width/2.

This is defined in ~/src/Mod/PartDesign/Gui/ViewProviderDatumPlane.cpp, line #134 setExtents(double l, double w):

Code: Select all

    pCoords->point.set1Value(0, l, w, 0);
    pCoords->point.set1Value(1, 0, w, 0);
    pCoords->point.set1Value(2, 0, 0, 0);
    pCoords->point.set1Value(3, l, 0, 0);

By changing this to :

Code: Select all

    pCoords->point.set1Value(0, l/2, w/2, 0);
    pCoords->point.set1Value(1, -l/2, w/2, 0);
    pCoords->point.set1Value(2, -l/2, -w/2, 0);
    pCoords->point.set1Value(3, l/2, -w/2, 0);

The Datum Plane should be centered. Can I make a PR for that ? Is there a very strong reason to have the current solution ?

[vocx]

Hello,

Datum Planes (PartDesign::Plane) can have either automatic dimensions, or manually set dimensions, for the 3D viewer. ...


The Datum Plane should be centered. Can I make a PR for that ? Is there a very strong reason to have the current solution ?

I don't oppose the change that you propose, I just want to mention that the plane does center automatically around the origin when you attach it to a coordinate system, like the PartDesign Body's Origin. However, as I tested a few things, it seems that the automatic positioning doesn't work in all cases, like sometimes it is buggy and stays where it previously was. You need to change a value of a position to trigger the update.

I also noticed an unrelated issue, if I saved a plane with certain dimensions, after re-opening the file, the dimension would be lost. Say that I specified 40 mm and 40 mm in width and length, after re-opening the file it would be 40 mm and 60 mm. I'm not sure if this is entirely repeatable.

So, my advice before going through with this pull request would be to test different combinations:
* with attachment, automatic and manual dimensions, and changing the Base placement and Attachment offset.
* without attachment, automatic and manual dimension, and changing the Base placement.

[chrisb]

In manual ResizeMode DatumPlanes behave here always as zolko described. Even if the DatumPlane is attached to e.g. XY-plane the DatumPlane is shown with a corner in (0,0,0).

[RatonLaveur]

Hello,

I agree with the suggestion, a more consistent datum plane behaviour is definitely a worthwhile endeavour.

here I take the liberty of adding this link https://forum.freecadweb.org/viewtopic. ... 0&start=90 from the Part Design Development forum. I think any kind and smart soul tinkering with Datum Planes would benefit from the context of all other Datum Plane "requests" (more like wishes/conversations).

I like to quote DeepSOIC on the matter who summed up very well the result of pages and pages of discussion.

So, for a potential developer (me, possibly), here's a list of things to do.
* add CS marker to datum planes, at least for the time it is being attached.
(that way, it will be easier to understand what roll,pitch and yaw do)
* (if possible) make datum plane's top and bottom look different.
* new attachment mode for sketches, to treat a plane as a plane.
* make the new attachment mode default for sketches made on datum planes.
* an option in preferences to change it back, for those who can't adapt to use LCS instead of a datum plane.
* make it easy to attach sketches to LCS object in PartDesign.
Does that sound good?

Of course, to that list we should now add "more consistent origin attachment behavior and extension of the representation of the plane".

The whole idea if summed up by me is:
- Make the X Y Z LCS of the DatumPlane visible during creation/attachment to make the user aware of the plane orientation.
- Make Top and Bottom of the plane visible somehow to better know where a sketch will appear (this would allow the user to not have to play constantly with "reverse mappings" which do have their own problems.

I believe these points link quite nicely to Zolko's original request above, since they all boil down to an easier and more consistent attachment of planes.

Cheers Gents,

[adrianinsaval]

* (if possible) make datum plane's top and bottom look different.

- Make Top and Bottom of the plane visible somehow to better know where a sketch will appear (this would allow the user to not have to play constantly with "reverse mappings" which do have their own problems.

My understanding is that if the LCS is displayed then the normal vector (Z axis) would give you the orientation, so there's no real need for different colors or anything like that. I agree with everything else, it would be more intuitive.

[Zolko]

So, for a potential developer (me, possibly), here's a list of things to do.
* add CS marker to datum planes, at least for the time it is being attached.
* (if possible) make datum plane's top and bottom look different.
* new attachment mode for sketches, to treat a plane as a plane.
* make the new attachment mode default for sketches made on datum planes.
* an option in preferences to change it back, for those who can't adapt to use LCS instead of a datum plane.
* make it easy to attach sketches to LCS object in PartDesign.

I believe these points link quite nicely to Zolko's original request above, since they all boil down to an easier and more consistent attachment of planes.

these things don't have not the same level of complexity: my proposal is a trivial minor change in the visual representation of a datum plane, it doesn't need any new tricks, and it shouldn't make any core difference in FreeCAD. In other words, it could be accepted without any risks of regressions, it's a purely visual artefact.

The other proposals, while more elegant, are also much more intrusive, and would need much more time to code and test.

[RatonLaveur]

Oh Zolko, we agree on this one. Except the visualization thing.
I simply felt like trying to keep similar concepts together so that whoever is tackling your request also has this in mind. Perhaps it is misguided however, to give too much information. Maybe I'm being counterproductive.

One thing is for sure if you want your datum plane to be precentered and easily scalable visually, I feel like adding the positive Z axis visualization doesn't hurt either either way your request sounds great.

[Zolko]

This is defined in ~/src/Mod/PartDesign/Gui/ViewProviderDatumPlane.cpp, line #134 setExtents(double l, double w):

Code: Select all

    pCoords->point.set1Value(0, l, w, 0);
    pCoords->point.set1Value(1, 0, w, 0);
    pCoords->point.set1Value(2, 0, 0, 0);
    pCoords->point.set1Value(3, l, 0, 0);

By changing this to :

Code: Select all

    pCoords->point.set1Value(0, l/2, w/2, 0);
    pCoords->point.set1Value(1, -l/2, w/2, 0);
    pCoords->point.set1Value(2, -l/2, -w/2, 0);
    pCoords->point.set1Value(3, l/2, -w/2, 0);

can I make this PR ?

Also: wouldn't it be nice if datum axes could also have a manual size ? Uodate would be needed for PartDesign::DatumLine.h, DatumLine.cpp and ViewProviderDatumLine.cpp. Thus, an axis could have a finite length. I think this would make the use of datum objects more widespread.

[vocx]

can I make this PR ?

You don't have to ask. You can just do it. If it's rejected then maybe you'll get feedback on why it wasn't accepted.

Linking to this discussion in the pull request is essential so that the admins know that it's been discussed, and agreed upon by the community.

[chrisb]

can I make this PR ?

You don't have to ask. You can just do it.

Formally you are right, but I think it is good habit to ask first in the community before making a pull request.