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In addition to the font size in pixels, which controls the 3D View font size (and indirectly the constraint icons),
it is now possible to configure a scaling factor controlling the width of geometry, axes, information layer, and
constraint lines.
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The aim is to easily differentiate a circle that is a normal circle from a circle that is internal geometry, no matter
if the normal circle is construction or not.
The underlying reason is that next commits will introduce a different treatment for internal geometry circles being B-Spline
poles, to which a new constraint Weight instead of a normal radius constraint will be applied, even though the representation
continues to be as circles.
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By default notification is on, so that Newbies do not complain why FC is deleting that other constraint they have added before.
Power users generally will set it off, as they do not want to be bothered by pop ups and know what they are doing.
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I makes the advanced solver taskbox by default disabled (not shown) and provides
a setting in Preferences->Display->Sketcher to enable it.
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When creating a type of geometric element, the user can create as many elements of that type he wishes without having to click the button before each insertion.
The insertion of that type of elements ends by pressing ESC or clicking the right button of the mouse.
This mode is by default disabled and can be enabled in Preferences->Display->Sketch->Geometry Creation "Continue Mode".
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This fixes a bug in the original implementation, that a non-driving constraint value could be
edited by double clicking on it in the 3D view.
It also includes minimal documentation on some functions.
It also includes:
- Color setting for non-driving constraints was not working.
- Settle UI terminology dispute:
* Driving Constraint (normal red constraint)
* Reference Constraint (non-driving constraint)
