A contour is a line of
points with a constant elevation, representing the natural contour
of the site. In Takeoff, there are two layer targets:
Existing Ground
Surface and
Design
Surface. Contour Polyline has two sub-command to digitize
contour lines into Existing Contour and Final Contour layers
directly for assigning them easily into Existing Ground Surface and
Design Surface in the future analysis.
There are two ways to digitize contour lines: sketch mode or point
mode. You can start digitizing a contour with one mode and switch
to the other during digitizing the contour. Sketch mode uses more
points than pick mode. In general, we recommend using pick
mode to digitize the straight parts of lines because it reduces the
number of points and speeds up Takeoff's calculations, but using
sketch mode to digitize the curved parts because it is fast and
accurate.
This command lets you
digitize contours as polylines one at a time. The first time it
prompts you the Digitize
Contours Dialog. Enter the layer name or select it from a
list of existing layer. Look at your plans and determine an
elevation interval that is between most of the contours and enter
it in the Elevation Interval field. You are able to modify both the
value and the direction of the elevation interval between
digitizing contour lines, using the buttons on the puck. To have
Takeoff automatically close contours whose beginning and ending
points are within a specified range, check the Auto Detect Close
Contour. Draw Labels would draw the elevation at the starting
point of the contour. In Pick mode, if you want the Takeoff to
automatically zoom the display to center around the last point when
you get near the edge of the screen while picking points, check the
Auto Zoom Center. Click OK to start digitizing.
If this is your first time digitizing a contour, you are defaulted
to the Pick Mode digitizing, otherwise you would be defaulted to
the last digitize mode. If you want to use the other digitize mode,
press 0 on the
puck or enter 0
from the keyboard. Place your cursor at one end of the contour line
and begin digitizing the line. While digitizing a line, you can
force a contour to close on itself by pressing A on the puck to end the
contour and connect the last point to the first point, remove a
mistake by pressing
B on the puck, or switch to the other digitize mode by
pressing 0. During
Sketch Mode digitizing, you can stop digitizing by
pressing Pick or Enter
button on the puck, take some rest or changes, and start
sketching again. At the end of the contour line, press Enter on your puck or keyboard.
The contour is completed, and the elevation for the next contour is
automatically incremented. You would be asked to digitize next
contour. If you press
A on the puck or enter Yes on the keyboard, you can
digitize another contour, or press B on the puck or
enter No on the
keyboard to finish digitizing contours.
Enter Layer Name,
Elevation Interval, and toggle on/off Auto Detect Close Contour
etc.
Increment(1.00)[A]/Direction(+)[B]/Elevation
<573.00>: 450 (enter elevation or press Enter to accept
current value)
Start
Digitizing...
Sketch[0]/Pick the first
point: pick
a point to start Pick Mode digitizing ( press 0 to switch to Sketch
Mode)
Sketch[0]/Close[A]/Undo[B]/Pick next point
(Enter to end): pick next
point
Sketch[0]/Close[A]/Undo[B]/Pick next point
(Enter to end): pick next
point
Sketch[0]/Close[A]/Undo[B]/Pick next point
(Enter to end):
0
(press 0 on the puck or
enter 0 on the keyboard to use Sketch
Mode)
Pick[0]/Close[A]/Undo[B]/Pick and drag (Enter
to end): pick and
drag
Drag to
digitize (Pick or press Enter to stop
sketching)... pick or press Enter
to stop sketching
Pick[0]/Close[A]/Undo[B]/Pick and drag (Enter
to end): B (undo the last
point)
Pick[0]/Close[A]/Undo[B]/Pick and drag (Enter
to end): B (undo the last point)
Pick[0]/Close[A]/Undo[B]/Pick and drag (Enter
to end): pick and drag
again
Drag to
digitize (Pick or press Enter to stop
sketching)... pick or press Enter
to stop sketching
Pick[0]/Close[A]/Undo[B]/Pick and drag (Enter
to end): 0 (press 0 on the puck or enter 0 on the
keyboard to use Pick Mode)
Sketch[0]/Close[A]/Undo[B]/Pick next point
(Enter to end): pick next
point
Sketch[0]/Close[A]/Undo[B]/Pick next point
(Enter to end): pick next
point
Sketch[0]/Close[A]/Undo[B]/Pick next point
(Enter to end): pick next
point
Sketch[0]/Close[A]/Undo[B]/Pick next point
(Enter to end): press Enter to finish
digitizing
Digitize Another Contour
[<Yes(A)>/No(B)]? B (press B to finish
digitizing)