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fixes#3084fixes#3061 (at least what it is understood in the analysis as being a bug, the visualization left).
Basically when deleting a feature, if it is the base feature (feature with which it will merge or cutout), the dependent objects'
base feature is made to be the base feature of the object being deleted. This code pre-existed at body level, but was not being called (see below).
Additionally, if the visible object is not the one being deleted, we leave that one visible. If the visible object is the one
being deleted, we make the previous object visible.
Deletion from the tree of a feature is handled by Document.removeObject, which has no clue about what a body is. Therefore, Bodies, although an
'activable' container, know nothing about what happens at Document level with the features they contain.
The Deletion command StdCmdDelete::activated, however does notify the viewprovider corresponding to the feature (not body) of the imminent deletion
(before actually doing it). Consequently, the only way of notifying a body of the imminent deletion of one of its features so as to do the clean up
required (moving basefeature references, tip management) is from the viewprovider of the feature being deleted.
-Hide all visual properties of features when they are part of a body
-Propagate all body visual changes to features
-Separate display mode from body mode to enable setting display mode for both "tip" and "through" modes
-Use default visuals for body shape and only make "through" a new display mask mode for the children
In most cases getBaseObject() is used with an exception handler which
only detects if it failed but not the reason. This modification allows
to use it without excess exception handlers.
Also add the same parameter to SketchBased::getVerifiedSketch().
- Moved all common code for part design features view providers to a base
class.
- Move shared code for Sketch based features to newly created
ViewProviderSketchBased class
- Add ViewProviderSketchBased to initialization
- Make Pad and Pocket ViewProviders to use the shared code
- Minor fixes to TaskFeatureParameters and some derived classes
