Depending on the input mode, either `Growth` or `Angle` is used to create
a conical or flat spiral. The respective other can easily be calculated
to give consistent view. This is already done for the other properties,
e.g. `Height` is calculated from `Pitch` and `Turns`.
With this patch, the same is done for `Angle` and `Growth`.
Introduce an enum to verify the axis depending on the used context.
* For helix no restriction is needed
* For Pad/Pocket the axis must not be parallel with the sketch plane
* For Revolve/Groove the axis must not be perpendicular with the sketch plane
Helices that become smaller with every turn are geometrically perfectly valid. Therefore we cannot forbid this.
(For example when creating a helix from a face you often cannot move it so that you can apply a positive growth.)
Previously, only the vertical and horizontal axis of the profile was
selectable in the task panel of the additive/subtractive helix. Now the
profile's normal axis can be selected, too. This now allows to create
helical extrusions or "twisted pockets".
The order of the GUI entries was chosen to be in line with the order of
axis selection of the multi-transform parameters.
The actual feature's implementation needed adaption for this special case
as in some places a unit vector (`gp_Dir`) was derived from the cross-
product of axis and profile normal -- a null-vector when the axis *is*
the normal. This caused the gp_Dir's ctor to throw.
- Helix: the property Turns has the App::PropertyFloatConstraint thus also the pointer to it must have the same property
- LinearPattern and Helix: make constraints static class member (forgot this in commit 3704ad68)
- Draft: make the constraint const
- PolarPattern and LinearPattern assure that the header file is loaded at last to avoid potential troubles
These features, based on the code for the Pipe class, allow the user
to simply create a helical sweep within PartDesign workbench.
Sample application is threads, springs, coils, augers, etc.
Also, remove needless requirement for positive cone angle on helixes.
Thanks to @bitacovir for helping with the icons
Thanks to @chennes for review
Thanks to @vosk for review
Thanks to @wwmayer for review
Enforce that links stay within scope for ProfileBased features
This also ensures that the Body itself is not used for creating features within
the body, causing a "Graph not a DAG" error.
