Adding Source Data by Grid Method Entry

The Grid Method Entry command creates a rectangular grid of points on the screen, and prompts you to enter the elevations of those points. The Create Site Model command then creates a topographical model based on those points.

Use this method when the source data is extracted from a paper map. Draw a grid on the map, and then determine the elevation of each grid intersection by interpolation between adjacent contour lines. Use these elevation values to create the grid.

To generate source data with the Grid Method Entry command:

1.	Select Landmark > Survey Input > Grid Method Entry (Landmark workspace) or AEC > Survey Input > Grid Method Entry (Architect workspace). When prompted, click at the upper left corner of the grid.

2.	After the starting point is picked, the Point Entry Grid Setup dialog box opens.

Enter the number of rows and columns of points to be created, as well as the distance between the points (Grid Spacing), and then click OK. A grid of red 3D loci is created.

3.	The Enter Z Values dialog box opens.

The first point on the drawing, at the upper left hand corner, is automatically selected. Enter the elevation of the point, and click Next. The elevation is applied to that point, and then the second point in that row is automatically selected. Enter the elevation for that point; continue until elevations have been entered for all of the points in the grid, and then click Done.