Project to Surface

On the Design tab, in the Editing group: Click Project | Project to Surface to project a selected string to a defined elevation and drape it along a given slope onto a specified surface. If no strings are selected when you click this tool, the Selection Assistant will prompt you to select the string or strings you want to project.

1. Select the string to be projected and click Accept.

   The selection assistant will progress to Step 2.

2. Select the surface to project the string onto and click Accept.

   The Project to Surface form opens.

Slope

Enter the Slope angle for the string projection in degrees. The value must be between 0 and 90 degrees.

Elevation

Specify the Elevation for the string projection in the field provided.

Expand

Select whether to expand the string Out or In for the projection.

Auto fillet

The Auto fillet option applies whatever fillet radius is needed to determine the arc of a curve. Acute angles are automatically smoothed, so in some cases you may prefer to leave this option Off. The option is not enabled for Project In.

Clean resulting strings

Select this check box to remove any unwanted object artefacts which may appear if the projection angle correlates closely with the slopes on an undulating surface DTM.

Preview

Clicking the Preview button will collapse the String form and display a preview of the direction for the configured projection:

Note: The Project to Surface tool may produce unexpected results if the surface contains steeply dipping sections that are similar to the slope value specified in the form.

The following example shows a scenario where the surface contains steeply dipping sections. The highlighted (blue) string is the selected string that is projected. The red string is the resultant string when the drape option was enabled:

The selected string is projected to the defined elevation. To understand the resultant string, imagine a wireframe being produced using the input string and the projected string. The intersection between the wireframe and the surface is used to derive the resultant string:

Forms

Click the Forms button to select and open a saved form set, or if a form set has been loaded, save the current form set.

Manage

To save the types, attributes and names you have defined and re-use them in other functions, click the Manage button to create a form set or load an existing form set.

Save

Click Save to save your changes as the default form set.

Save As

Click Save As to save your changes as a new form set.

Reset

Click Reset to clear the form of all values and reset the form to its default state.

OK

Finally, click OK to project the selected string or strings.