VTBuilder

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Structure Layers

Built Structure data includes buildings, fences, and other artificial structures not described by other layer types.  The native file format for Structure files is VTST files.

You can also import Structure data from Shapefiles.  The Shapefile should contains arc (polygon) data, which will be interpreted as building footprints.

If you have another source of building location/footprint data that you would like to import, please let us know.

Structures Menu

• Select Features
  • In this mode, you can select structures (by clicking or dragging the left mouse button) and edit their properties (by click the right mouse button).  Properties you can edit include:
    • Color
    • Number of Stories
    • Roof Style
    • Materials
• Edit Buildings
  • In this mode, you can edit the shape and location of buildings:
    • Grab the center of a building to move it or grab a corner to resize it
    • Hold down Shift and grab the corner of a building to evenly scale it
    • Hold down Ctrl and grab the corner of a building to rotate it
• Add Points to Building Footprints
  • In this mode, you can click on the edges of buildings to add points to the footprint.  If the building has multiple levels, the point is added to all levels.
• Delete Points from Building Footprints
  • In this mode, you can click on points of the building footprint to remove them.  If the building has multiple levels, the point is removed from all levels.
• Add Linear Structures
  • In this mode, click with the left mouse button to create linear structures, such as fences and walls.  The linear structures dialog will appear to allow you to select what kind of feature you want.  Click with the right mouse button to finish the structure.
• Edit Linear Structures
  • In this mode, you can use the left mouse button to drag the points which define linear structures.
• Add Foundation Levels to Buildings
  • Constructs an additional "foundation" level to each building, which can help with the common problem of low-resolution elevation data which has slopes and buildings on it.  The buildings in this case can look unrealistically "embedded" in the terrain.
    The height of the terrain is evaluated at each point of the building's footprint, and if there is a vertical range of greater than 0.5 meters, then the "foundation" is constructed.  The foundation consists of a slab of cement-block which is just high enough to elevate the building, to prevent any of the non-foundation levels from intersecting the ground.

Importing Structures from Raw GIS Data

This is the easiest way to populate your terrain with a lot of structures if you already have GIS data for their locations.

1. Use the "Layer: Import Data" command and select "Structures" as the layer type.
2. Select your Shapefile (*.shp)
   Shapefiles with polygon data can be turned into building footprints.
   Shapefiles with arc data can be turned into fence lines.
   Shapefiles with point data can be either building centers, or instance locations.
3. Indicate how to interpret the Shapefile (one of the above 3 meanings)
4. Optionally, you can restrict the import to only use features that lie within your Area tool.  This is useful if you have a massive GIS data source and only care about a specific area.

The data will then import, so you can review it and save to VTST.

Attributes for Instances:  In addition to the filename file which you can specify in the Import dialog, the following optional fields will be recognized in your input SHP if they are present:

• itemname - The item name of the model to show (from a content file).
• scale - Scale for the instance model, e.g. a value of 3 means to scale the model by 3x in all dimensions.
• rotation - Rotation for the instance model, around its vertical axis by the indicated number in degrees.

Attributes for Buildings:  Building footprints will be created with the default attributes of 1 story, flat red roof.  If there is a SHP field called "stories", it will be used for the number of stories.  There are plans to eventually extend this functionality to allow any of the fields to be mapped onto any attribute.

Remember that when you are ready to use VTST data with Enviro, you should put it in the "BuildingData" folder on your Data path.

If you want to apply a default appearance to all the buildings you import, you can use the Default Structures feature.

Default Structures

To tell VTBuilder about defaults for structures, create a VTST file with one or more structures (Buildings) which have the desired appearance.  Name this file DefaultStructures.vtst and put it in a "BuildingData" folder on your Data path.  Then, whenever VTBuilder imports structures from raw GIS data, it will look at the defaults and copy visual appearance (materials, story heights, roof types, etc.) to each newly imported structure.