ET Surface Toolbar

For users of ArcGIS Desktop ET Surface toolbar provides the following functionality:

Select Surface Layer

The selection combo box is used to set the current surface layer.

Profiling tools

The Profiling tools are used to create profiles in the Profile Extractor - see the Profile Extractor pages for detailed information.

Line of Sight tools

Line of Sight tools are used to create Line of Sight profiles in the Profile Extractor - see the Line of Sight pages for detailed information.

Digitize Z Shapes

The Digitize PointZ , PolylineZ and PolygonZ tools extract for each geometry digitized the Z values from the surface selected in the Surface Layer box and create Z shapes.

If the user digitizes polylines or polygons new vertices are introduced in the digitized geometry depending on the source surface:

• If the source surface is Raster, the user can change the sample distance to control the number of vertices introduced in the digitized shape. To change the sample distance press the "S" key when the tool is active.
• If the source surface is a TIN, new points are inserted at the intersections of the digitized geometry with the edges of the TIN triangles.

The tools can be used to digitize features or graphics

• IN an Editing Session: If the target layer is set to a Z enabled layer of the type the user digitizes, the geometry captured will be stored as a feature in the target layer otherwise it will be stored as a graphic element. If for example the target layer set in the Editor is of PointZ type and the tool used is Digitize PointZ, the geometry will be stored as a feature. If however the tool used is Digitize PolylineZ, the geometry will be stored as a graphic element
• OUT of an Editing Session: the geometries digitized are stored as graphic elements. The default symbols (set in Drawing ==> Default Symbol Properties) are used for the graphic elements.

Manage Graphics

The tools of ET Surface draw many graphics elements on the view. This tool allows to manage these graphics elements with ease. It opens the following form:

• Upon executing the command all graphics elements in the view are collected. The unique names are populated in a combo box and the user can select a name from the list or type one. If the Graphic Name box is left empty, all graphics will be considered in the selection criteria.
• The types of available graphics are populated in the graphic type combo box
• There are three selection options
  • New Selection
  • Add To Selection
  • Remove From Selection
• The user has options to quickly delete or group selected graphics.

Watershed tool

The Watershed tool is used to delineate a Watershed for a selected point on the surface. The delineation is based on a D8 Flow Direction raster which has to be selected in the Combo box.

For better visualization the DEM raster should be displayed on top of the Flow Direction raster.

The delineation is usually done for a point on a stream and if there is no Stream layer available sometimes it is difficult to select the correct location.  In such a case it is useful to use the Flow trace tool to create a Flow path and then use the Watershed tool based on the flow path.

An example of the Watershed tool output.

Flow Trace tool

The Flow Trace tool is used to create a Flow path for the water from the specified point over the terrain to the Outlet.  A Flow Direction D8 raster has to be selected in the Combo box in order to use the tool.

An example of the Flow Trace tool output.

Raster Cell Inspector

The Raster Cell Inspector tool is used to view cell values of the Raster dataset selected in the Selection Combo box. It will display the value of the cell under the cursor as well as the neighbouring 8 cells.

As the mouse pointer is moved over the Raster with pressed left button, the values will change for the current cell under the cursor.

The Cell inspectow window contains other useful information - the current raster cell size, data type, minimum and maximum values, and the NoData value.

The current cell position in the raster is shown in the boxes above and on the left side of the cell values grid - X from left to right from 0 to the maximum width and Y from top to bottom from 0 to maximum height.

The two boxes below the cell values grid display information based on the selection at the bottom of the form as follows:.

• When is selected - the X and Y coordinates of the current cell center.
• When is selected - the slope and aspect of the surface in the current cell.
• When is selected - the plan and profile curvature in the current cell.
• When is selected - the flow direction (D8 and D-inf) in the current cell.

The precision of the displayed values can be increased and decreased with the precision arrows.

The Color coding drop-down allows for color coding of the minimum and maximum values displayed in the cell values grid.