The positions of the Sections, Waterlines, Buttocks, and Diagonals form what is called the Grid. The grid can be displayed on any window by selecting the Grid command from the Display menu. Elements can be added to the Grid by using the Grid Spacing function from the Data menu.
The positions for each of the grid elements are stored in individual lists, which may be selected by clicking on the labelled buttons in the top right hand corner of the Grid Spacing dialog box (region 1 of the dialog in image below).
The Grid Space dialog can be divided up into the following regions:
1. Select the type of grid you want to work on, i.e. Sections, Buttocks, Waterlines or Diagonals
2. Commands to Add, Delete, Sort or Space the grid type selected in 1
3. Displays the current grid locations for the grid type selected in 1
4. OK and Cancel to confirm or undo any changes made in the dialog
The positions of Grid elements are as follows:
Sections
Position of each section relative to the longitudinal zero point. Positive numbers are to the right (forward), negative numbers to the left (aft) of the zero point.
Buttocks
Position of each Buttock relative to the centreline of the hull.
Waterlines
Position of each waterline relative to the vertical zero point. Positive numbers are above, negative numbers below the zero point.
Diagonals
Two columns of figures are provided, centreline height and angle. The centreline height is the position of the origin of each diagonal relative to the vertical zero point. Positive numbers are above, negative numbers below the zero point. The angle is the angle between the diagonal and the centreline as shown below. Angles above 90 degrees will give diagonals above the centreline height.
Watch a short video
that shows you how to setup the Frame of Reference and the Zero Point and
define the Grid.
To add one or more grid lines
§ Select the row after which the new grid lines are to be added.
§ Click the Add button.
§ Enter the number of grid lines to be added to the list.
All new position fields will be initialized to zero.
The number of Grid elements is limited to the following maxima:
§ 1000 Stations
§ 100 Waterlines
§ 100 Buttocks
§ 50 Diagonals
To space a group of stations along the Datum Waterline or overall length of the design,
§ Click the Space button.
A dialog will appear with options for spacing the stations.
§ Select Evenly Along Datum Waterline or Evenly along the length of the model, as desired.
§ Click OK.
To space grid lines at a specific intervals
§ Select From and enter the numbers of the grid lines to space
§ Enter the required interval between grid lines.
§ Enter a starting position to space from.
§ Click OK.
You may also specify the range of grid positions by simply selecting those rows in the Grid Spacing dialog. In this case, the start and finish grid lines, a default spacing and a starting position are set up automatically.
Similar functions are available for spacing the waterlines and buttocks.
To edit a grid line position
§ Select the cell corresponding to the position you wish to edit.
§ Type in a new value.
Dimensions entered in units other than the current units are converted automatically.
Grid Labels can be specified by entering text into the first column of the table. Grid labels are used for labelling the grid when printing or plotting, and for inclusion in the Table of Offsets.
To sort grid lines
§ Click the Sort button.
Sorting occurs as follows:
Stations: Longitudinally.
Buttocks: Transversely.
Waterlines: Vertically.
Diagonals: Vertically - centreline height only.
The Grid Spacing dialog allows copy and paste operations to take place on the tables of grid names and positions. As the main menu bar is not accessible from within the dialog, copy and paste are achieved using the standard command key equivalents, Ctrl C for copy and Ctrl V for paste.
To delete one or more grid lines
§ Select the row corresponding to the last of the set of grid lines to be deleted.
§ Click the delete button.
§ Enter the number of grid lines to be deleted.
§ Click OK.
If a range of rows is selected in the Grid Spacing dialog, the corresponding number of rows is automatically set in the deletion dialog. These rows will be deleted when you click the OK button.
If you have imported or defined markers with common longitudinal, transverse or vertical positions, you can automatically generate a grid from these markers. The Generate Grid from Markers command will automatically generate the grid (sections, buttocks and waterlines) based on the marker data and also associate markers with the correct marker station index. (See Working with Markers on page 68). Sections are generated at the markers’ longitudinal position; buttocks at their transverse offset; and waterlines at their vertical location:
Using the checkboxes you can select which items of the grid to generate (i.e. stations, buttocks and waterlines). Then, using the radio buttons, you have the option of deleting and replacing the existing grid data or adding to the existing grid data. You can also specify how many markers must be at the same longitudinal position, transverse offset or vertical location for a station, buttock or waterline (respectively) to be added. Finally, you can specify a tolerance for markers to be considered at the same plane: for example if the Marker plane separation tolerance were set to 0.001mm then markers up to 1mm apart (in longitudinal position, transverse offset or vertical location) would be considered to be in the same plane and the station, buttock or waterline location would be averaged.
When Importing DXF Markers or GHS markers, Maxsurf can automatically generate the grid. The section grid is generated automatically only if no existing sections are defined. If sections are already defined then imported markers that lie within 1cm of a section will be allocated to that section, otherwise they will be left unallocated.
Also see Displaying Contour Lines on page 24.