Polygon control points: change the style to the semitransparent filled rectangle.

This also solves the problem when the contour is copied,
resnapped. In previous version two points were snapped to the same coordinates, so the control point were becoming invisible.

Spline\Polyline entities: fixed the defect when the control point is selected, moved outside the document area and becomes unreachable.

Added the menu item   MainMenu>Trace>MagTrace

Implemented a support function to output the Edges used by MagTrace for the current slice.
Currently selected MagTrace parameters are used so it is a 1-click operation.

Corrected the "HitTest" on mouse click over the Spline entity.

Corrected the defect for the HitTest mouse click on the polyline.

Modified the ToolTip for the "Width\Level" button of the Main toolbar.

Added   "MainMenu>Trace>Application specific settings" ability for {Femur,Hippocampus} applications.

MagTrace tool: implemented 2 new UI-level functions
a) Snap Selection to Image
b) Copy from adjacent slice and Snap to image.

MagTrace on Hippocampus.

First experiment:  To evaluate the quality of snapping, I used the supplied HC Roi as the guidance.  I clicked precisely on the boundary of the HC-ROI and let the software to adjust the position.
Attached screenshot shows the snapped points, without any manual further corrections.
Note: the snapping was performed on x3 upsampled resolution (EMD\Radial\2.2).

MagTrace:  Restart tracing> fixed the Bug when user had polyline selected on a different slice from currently  MagTrace operational slice.

FireVoxel Build 211 is released.

1.  First version and user interface for the MagTrace semi-automatic tracing functionality.

MagTrace tool:  implemented functionality to resume the tracing of the existing Spline
a) Select the desired spline
b) Press MagTrace button.  Operation will resume from the last point.

Magtrace tool:  prevented the "Double entry" error when user presses snap button before the previous snap operation is finished.

MagTrace tool:  fixed crash when the user clicks within the document window, but not on the image.

PolyTool\MagTrace tool:  don't perform any action if the mouse cursor is out of client are.
(affected:  MouseMove and MouseLButtonDown)

MagTrace: implemented various support function for Splines:
a) UpdateRectangle calculation
b) Spline contour hit test.

Implemented the Spline\Polyline rasterization function.
Several contours and\or holes are allowed.
Spline - polygons could be mixed.
Internally this supports 2.5D polygons (i.e. 2D+SliceIndex).

Created new C++:CDrawTool  "Magnetic Trace" and added a corresponding menu item to avoid cluttering the Polygon functionality.

Improved the semi-automatic "Snap-To-Point" function and corresponding UI.
This is mostly due to better matching and usage of Splines.

Initial pass: user quickly clicks on desired location and proceeds WITHOUT correction

On the second, manual pass, user simply drags the control points (about 5-6) in this example and contour adjusts.