GeoTools->Build

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The Build tools are a set of tools that help in creating new objects from existing ones.





Toolbar : Build  
      Menu : GeoTools Build
Make rights-of-way / pavements / ramp
Command line : GT_ROWMAKER 


Build rights-of-way by ofsetting center line on both sides

The GT_ROWMAKER command can be used to create right-of-ways by offsetting a road center line on both sides by a specified distance. It can be used with both 2D and 3D polylines, as well as polylines with arcs and Spline objects.

Width of right-of-way: Specify the width of the right-of-way.
 
Select R-O-W layer: Select the layer into which the newly created ROWs must be placed.




Toolbar : Build  
      Menu : GeoTools Build Draw center from road R-O-W
Command line : GT_CENTLINE 

The GT_CENTLINE command is used to create road center lines from right-of-ways. The user must draw zig-zag lines across the right-of-way along its entire length. The mid-point of the segment of the zig-zag line that intersects the right-of-way is taken as the road center line point and the line joining a series of such center line points forms the road center line.


Command: GT_centline

Digitize Road Center Lines from Rights-Of-Way:
Pick Start point of line: <do so>
First zig-zag point: <do so>
Generate/Jump/Manual/Undo/eXit:<Next zig-zag point>: <pick a point or Type G, J, M, U or X>
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Upon starting the GT_CENTLINE command, you are asked to pick the start point of the road center line. Pick a point as shown in the illustration above. A sub-menu appears which provides the following options:

Generate/Jump/Manual/Undo/eXit <Next zig-zag point>:

The default option is to pick the next zig-zag point. In the illustration above, the zig-zag lines are shown by the red lines. GT_CENTLINE determines where each zig-zag line exactly intersects the right-of-way and calculates the mid-point between them as the road center line point.

Generate [G]: The Generate option is used to display the road centerlines drawn so far.

Jump [J]: The Jump option is used to temporarily suspend the digitization of a zig-zag point. This is an on/off toggle. This option is typically used when you want to skip certain areas and would like to move the zig-zag point to another place to continue the digitizing.

Manual [M]: The Manual option allows the road centerline points to be manually digitized. This option should be used when it is easier to specify the road center-line point by a direct pick rather than by the zig-zag method.

Undo [U]:
The Undo option allows the last digitized centerline point to be undone.

eXit:
The X option exits the GT_CENTLINE command and creates the road centerline digitized so far.



 

Toolbar : Build  
     
Menu : GeoTools Build Offset 3D polylines by X & Y distances
Command line : GT_3DOFFSET 

The GT_3DOFFSET command is used to offset 3d polylines in the same manner as 2d polylines. 3D polyline can be offset both horizontally and vertically. This can be a very useful in several civil engineering design situations that require the offsetted polyline to be offsetted and elevated or lowered by a fixed amount relative to the source polyline.


Toolbar : Build  
     
Menu : GeoTools Build Offset 3D polylines by Slope & Elevation
Command line : GT_3DOFFSETSLOPE 

The GT_3DOFFSETSLOPE command is used to offset 3d polylines by providing a slope angle (either in degrees or in 1:n format) and a desired change in elevation. This is an extension of the existing GT_3DOFFSET command that does 3d offsets by horizontal and vertical distances only.

Toolbar : Build   
     
Menu : GeoTools Build Draw centroidal marks inside closed polylines.
Command line :
GT_CREATECENTROID

The GT_CREATECENTROID command is used to create centroidal marks inside closed polylines, splines and circles.

Layer to create in:

Source: Creates the centroidal marks in the source layer( i.e the layer in which the closed polylines reside).
Current: Create all the centroidal marks in the current layer
Specify: Choosing this option allows specifying the layer in which the centroidal marks will be created.
Select: Clicking on Select button pops up the Select Layer dialog box. 


Object to create: Specifies the type of object to create.

ACAD Point: An AutoCAD/BricsCAD point object is created at the centroidal location of each closed polyline.
Running Text Number: A Text string is created which is incremented by 1 each time for the next polygon being annotated with centroidal marks.
Fixed Text string: A fixed text string value is used for the annotation of the centroidal mark. The value of this text string is specified in the edit box provided for it.

Start Number: Specify the start number to be used for the annotation, if the Running Number Text option was chosen.
Format Width: Specify the required format width. This will prefix Zero before the running number text such that the string length is atleast equal to the format width specified.
Fixed Text string value: Specify the value of the fixed text string to use for annotations.
Text Height: Enter the height for marking the Text string or Running number text.

Ensure that the centroidal point always falls physically inside polygon: If this option is checked and if the centroidal falls outside the polygon, it will be moved to a location physically inside the polygon.

The GT_CREATECENTROID command has an option to run without the dialog box selector. To enable this, you much check the option within the dialog box which says "Hide dialog box and run GT_CREATECENTROID in command-line mode next time". This setting is not saved in registry and revets back to dialog box mode when your CAD is re-started.

Toolbar : Build  
     
Menu : GeoTools Build Mulitple variable measure command
Command line : GT_MVMEASURE 

The GT_MVMEASURE command allows multiple and variable distances to be measured along lines and polylines.

Specify segment length

Cumulative - From beginning of line: Select this option to mark the user specified distance on the polyline.
 
Each segment: Select this option to mark the user specified distance relative to and following the previous segment.

Place blocks at measured points: This option allows you to select a block from the current drawing which will be placed at the measured point locations

Break at measured points: This option breaks the polyline at each of the measured positions.

Align block with object: Check this option to align the block with the slope of the line at each point.

Place at first and last point also: Checking this option automatically places a block or point at the first and last vertices of the curve.

Scale Factor: Specify the required scale factor for the block


GT_MVMEASURE Tutorial

 

 

 

 

Toolbar : Build  
      Menu : GeoTools Build Join nearest ends of lines / polylines.
Command line : GT_JNE
The GT_JNE command is used to join the nearest ends of two selected lines and/or polylines with a connecting line and optionally join all the three into one single polyline.

Command: Select first object: (do so)
Select second object: (do so)
Join all segments together? [ Yes/No ] <Yes>:






Toolbar : Build  
      Menu : GeoTools Build Build common edges along closed adjacent polygons
Command line : GT_EDGEBUILDER




The GT_EDGEBUILDER command is a tool useful for building edges along adjacent, closed polylines. A typical scenario in GIS data preparation or modeling involves creating intersection-to-intersection edges on a network of closed polygons adjacent to each other. The GT_EDGEBUILDER command is an attempt to fulfill this need in an easy way.

Like in every GeoTools command, it is best to start with data that is as clean and accurate as possible. BEFORE you start this command, it is essential that all duplicate segments from the selection are removed and cleaned using the GT_DISTANGWEED command.

 

 

Toolbar : Build
      Menu : GeoTools Build Interpolate point elevation from neighboring polylines - manual pick
Command line : GT_PTINTERMANUAL

The GT_PTINTERMANUAL command is useful to assign point elevations by interpolating the elevations of neighboring polylines.  


Toolbar : Build
      Menu : GeoTools Build Interpolate point elevation from neighboring polylines - automatic
Command line : GT_PTINTERAUTOMATIC

The GT_PTINTERAUTOMATIC command is useful to assign point elevations by interpolating the elevations of neighboring polylines automatically by scanning specified layers.

 

 

 

Toolbar : Build  
      Menu : GeoTools Build Create closed polylines from a mass of networked polylines
Command line : GT_CCPOLY




The GT_CCPOLY command is used to create closed polylines from a mass of inter-networked polylines, lines, arcs and circles. It is nothing but an automated version of the BPOLY command and it applies BPOLY at regular intervals in X and Y directions along a rectangular grid and creates closed polylines (resulting from BPOLY) from the adjoining boundary set. The program uses a parameter called 'Scan Window Size' to determine the BPOLY sampling interval. Needless to say, the GT_CCPOLY can be quite slow in its operation because it has no intelligent way to know how many unique closed polylines would be created. Since the BPOLY sampling is done at each regular interval, the program takes more time if the sampling interval is smaller and vice versa. Nevertheless, the program can be useful in many cases. Use it appropriately by specifying a scan window size that works with optimum speed and accuracy.

Scan method:
Automatic: 

At selected points: 

Scan Window Size: Enter the amount of search (scan) size 

Zoom Window size: Enter the amount of zoom size. 

Select Layer for closed polylines :
Clicking on this button pops up  the dialog box for selecting the layers of closed polylines

Select Layer for polygon edges : Clicking on this button pops up  the dialog box for selecting the layers of polygon edges.


Toolbar : Build  
      Menu : GeoTools Build Create a mathematical relative contour offset between two polylines
Command line : GT_CONTOUROFFSET




The GT_CONTOUROFFSET command can be used to create an offset polyline in between two given contour polylines.
 
This command will ask the user for two polylines representing two contours and will create an intermediate "offset" polyline at the correct interpolated elevation between the two polylines.
 
The location of vertices for the offset polyline will be determined on the basis of configurable parameters like 'Offset Percent' (percentage distance between the two polylines) or an absolute distance from a point on the first polyline and measured towards a similar point on the second polyline.

The algorithm used to determine the offset polyline positions is not yet perfect to handle polylines of all geometric shapes. Often, the command may create offset polylines which are completely unacceptable as an interpolated offset. We would like you to be aware of these limitations.

To overcome some of these bugs, you may run the command again reversing the order of pick for the first and second polylines. This may sometimes produce better results.

Alternatively, you can also try to apply either of the two algorithms that the program uses. If one algorithm does not work for one set of polylines, the other might work or produce better results.

To determine a match point on the second polyline, the program uses a technique which is based on proportionally equivalent distance matching between and along the two polylines.

Algorithm to use:

Method 1: Select this option to use the primary algorithm

Method 2: Select this option to use the alternative algorithm, if the primary algorithm does not work.

Offset Method:

Percentage: If you select this option, the offset polyline will be created at the specified percentage distance between the first polyline and second polyline.

Distance: If you select this option, the offset polyline will be created at the specified distance from the first polyline towards the second polyline.

Sampling Method:

At Each vertex: The offset polyline created will have only as many vertices as the first source polyline.

At sampling interval: If you select this option, the first polyline will be sampled according to this interval and for each of these sampled points, the corresponding offset polyline points will be generated.

Sampling interval: Enter the distance along the first source polyline to create sampling points, which will then be used to create offset polyline points.

Percentage distance from first polyline: Enter the percentage distance from first polyline at which to create the offset polyline points.

Actual distance from first polyline: Enter the actual distance from first polyline at which to create the offset polyline points.

 

 

 

Toolbar : Build  
      Menu : GeoTools Build Place points at user defined spacing along linear network
Command line : GT_NETNODES

The GT_NETNODES command is used to place nodes (points) along a linear network of connected lines and/or polylines. This command performs a simple trace through the entire network and places points in such a way that that no two points are closer to each other than the specified distance which is measure along the network (and is NOT the straight line distance) between the two points. Please be aware that the command expects that the network is topologically correct, cleaned and that the end points of the lines are EXACTLY touching each other.

Distance interval for placing nodes : Specify the distance at which the nodes (points) have to marked.

Search window size : Specify the size for the search window as per the drawing unit.

Select layer to place nodes : Clicking on this button will pop-up the select layer dialog box for placing the nodes (points) in required layer.



Toolbar : Build Tools   
     
Menu : GeoTools Build Drape a 3D polyline across a set of intersecting linear objects
Command line: GT_DRAPEPOLY

The GT_DRAPEPOLY command can be used to drape a set of 3d polylines (source objects) over a set of intersecting linear objects (target objects). Upon draping, this command creates vertices all along the source objects (3d polylines) where they intersect the target linear objects.


Select source objects: (do so) - allows a filtered selection of 3d polylines only

Select target objects: (do so) - allows a filtered selection of linear objects like lines, polylines (both 2d and 3d), arcs and splines.

After GT_DRAPEPOLY runs, there will be new vertices created on the source polylines at every point where they intersect the target objects. If the intersecting objects are 3d, their 3d intersection value will be computed and used.

 


Toolbar : Build Tools   
     
Menu : GeoTools Build Split larger polygons into smaller ones
Command line: GT_POLYAREASPLIT

The GT_POLYAREASPLIT command is useful for those who want to proportion large closed polygons into smaller closed polygons cut to an exact target area. This is a useful tool in land acquisition and property parcel planning and sub-division activities.



The GT_POLYAREASPLIT command mimics the manual process of trial & error to arrive at the closest area value. You first pick a closed polyline which represents the larger polygon that needs to be splitted. Next, you must provide two two guide lines, one stationary and another that is moved in small increments in a direction that increases the area. The entire process can be interactive or automatic. As soon as target area is reached, the program stops.
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