Line Construction
Line construction is a function for designing a horizontal alignment, e.g., centerline.
Find it here:
MOUS_ICO Menu: Landscape > Construct Lines and Polygons > Line Construction
MOUS_ICO Toolbar: Construct Lines and Polygons: Line Construction
You start by selecting a line, arc, or polyline from the drawing or selecting an existing alignment from a file from the Object menu. The button Pick Object in the lower-left corner of the dialog is the same as the function Object -From Drawing. You can select one or several lines or arcs for the drawing. The first picked element sets the alignment direction. The direction of the alignment can be changed at any time with the function Turn from the Modify menu.
Minimum arc
Use the following procedure to define the minimum radius to be followed for the curves of horizontal alignment. Curves inserted through the function Insert Min. Arc where Line-Line will be according to the parameters defined in this function, which can be edited later. The dialog box 'Hor minimum Radius' (shown below) will pop up where you can choose Radius as the controlling factor. Select the desired factor and define the value. Radii that fall short of the defined minimum value are marked in red in the table as an indication.
Insert Min. Arc where Line - Line
Use this procedure to automatically insert arcs with minimum radius/length (define with the function 'Minimum Arc') between straight lines in the horizontal and vertical alignments. This procedure can be used for rapidly creating horizontal alignments. The initial geometry can be sketched using lines or polylines and arcs with minimum radius or length will be inserted automatically between the straights. The minimum radius or length of arcs should be defined before using this procedure. Set the arc parameters from the menu Data, Minimum Arc.
Tip: You can also activate this function from the right-click menu on the main dialog 'Alignment Design'. To activate this function from the right-click menu, select all the elements or at least two elements on the main dialog box (from the tab Input H), click the right button of the mouse, and select Insert Minimum Arc where Line-Line.
Successful Calculation
The status bar in the main dialog box 'Alignment Design' indicates if the calculation has resulted in a successful calculation on the status bar (Calc Ok) and the drawing/graphic is updated with the new alignment.
Failed Calculation
The status bar in the main dialog box 'Alignment Design' indicates if the calculation fails on the status bar (Calc not Ok). The drawing/graphic is then based on the latest successful alignment. When the alignment is edited without success, alignment in AutoCAD is indicated with colors that derive from the standard color setting. (Yellow, cyan, and magenta)
Further reading
Line construction is a very powerful tool, this version is adapted for Landscape. Read more about the full potential of this function in alignment_design.
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