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The Orca3D Document Properties is where Orca3D stores all of the properties that are available for you to manage.

 

In the Orca3D Document Properties you can edit several different items.

 

 

Start the command with the toolbar icon, menu selection or keyboard command.The Orca3D Document Properties Dialog Box will appear:

 

 

 

General Tab

 

Type the Project Title and Company Name that you wish Orca3D to use. These items are used in reports (hydrostatics, speed/power), and the lines drawing. They are stored with the model in the Rhino 3dm file.

The line titled "Logo File" is the filename and path of the logo file to be used in the reports. The file you wish to use must either be in bitmap or JPEG format, up to 192 x 72 pixels. You may type the path to the file into the text box, but a more convenient method is to click the button to the right labeled “ … ” and browse to the location of the logo file.

 

Orca3D Units Preferences

Select the unit system that you wish Orca3D to use.

"In general, Rhino works best if you choose a unit system whose absolute tolerance is around 0.01 to 0.001, the "size" of a small feature (like a tiny fillet or small curve offset distance) is >= 10 x tolerance, and the "size" of the model is <= 100000.

Using an absolute tolerance that is smaller than 0.0001 will noticeably slow some intersection and fitting processes." (for complete information, see "Document Properties: Unit Settings in Rhino's Help guide)

This implies that a typical vessel, designed in meters, could have the absolute tolerance set between 1 millimeter and 1 centimeter (0.001 to 0.01). If your model will have small features, such as fillets on the order of 1 centimeter in size, the tolerance should be closer to 0.001. If the vessel is designed in inches, a tolerance of 0.01 would be more reasonable. For a vessel designed in feet, perhaps 0.003 is appropriate.

Select the “Show Units … ” button to see a more detailed listing of the unit system. If you have any unit system besides custom selected, the a dialog similar to the following will appear:

 

You can select the different unit systems at the top and see which units are being used for each unit type. To the right of the unit is the abbreviation for the unit, and the conversion factor to SI units.

If you select Custom as the Unit System, the dialog box changes as follows:

Use the "Copy From" button to "initialize" your custom settings using one of the standard unit systems.

 

The change of the text color to red indicates that the properties are now available to be changed. If you select the plus icon next to any unit type, something similar to this will appear:

 

To select a different unit for this unit type simply check the box next to the unit. The abbreviations and conversion to SI are still viewable for your convenience. Customize each unit type at your discretion to fully customize the Unit System.

Select OK when finished editing the units.

 

Model Orientation

For various purposes, Orca3D must know which coordinate axis is longitudinal, which is transverse, and which is vertical, and further, what direction the positive sense of each of these corresponds to. For example, the definition of a "station" is a plane at a constant X value, if X is your longitudinal coordinate. And while the direction (positive X aft or forward) doesn't matter for hydrostatics calculations, it is important for speed/power analysis (the program needs to know which end is the bow). Orca3D defaults to a coordinate system with positive X aft, positive Y to starboard, and positive Z up. However, you can set the coordinates in any of 24 combinations, all of which are right-hand rule coordinate systems.

 

 

Note: Changing these values will not rotate your model. You must use the standard Rhino commands (Rotate or ScaleNU) to change the orientation of your model.

Orca3D always maintains a right-handed coordinate system. This implies the following:

If you choose a coordinate system with the Up direction set to a Negative direction, you may find that rotating the view in the Perspective viewport is non-intuitive. This is because by default, Rhino does rotations about the World Coordinates. To make it more intuitive, open the Rhino Options dialog (Tools > Options, or right-click on a viewport name and select Display Options). Click on View, and then select "Rotate relative to view."

 

 

View Tab

 

Orca3D Viewport Settings

These settings allow you to change the appearance of Rhino whenever you change to Orca3D Viewports.

Left-clicking and then right-clicking on the icon will toggle back and forth between your current layout and the OrcaViewports layout. Since the left-click will save your current viewport settings, if you left-click while you have the Orca Viewports displayed, you will be "stuck" in this mode. If this occurs, simply restore the default Rhino 4-view layout, by right-clicking on one of the viewport names (e.g., Profile, Perspective, etc.) and selecting Viewport Layouts -> 4 Viewports.

 

Control Polygon

Orca3D has its own control polygon system, which is similar to the control points maintained inside Rhino. If these polygons are edited, the hull and sections (and optionally the hydrostatics) are updated in real time. The Control Polygon Section allows you to control their display color and line type so you can easily distinguish them from typical Rhino control points.

The Control Polygons can be turned on and off by either going to (Orca3D > Hull Design > Orca3D Control Points On) in the menu, typing OrcaPointsOn in the command line, or clicking the icon in the Orca3D toolbar. Two example hulls with Control Polygons on are shown below:

 

 

 

 

On the hull, the U direction usually designates the longitudinal direction on the hull, and the V direction generally designates the direction from bottom to top on the hull.

Click the box to right of Polygon U color to select the color that you wish the U direction polygons and control points to be displayed in. Click the box to right of Polygon V color to select the color that you wish the V direction polygons and control points to be displayed in. Select whether you wish the polygons to be drawn with a solid line or a dotted line.

Rows in the net that correspond to chines that are created with the OrcaInsertChine command (or by any means that create multiple knots equal to the degree of the surface) can be drawn in a different color. By default they are drawn in red.

 

Hydrostatics Tab

 

Fluid Properties

Select either Seawater, Freshwater, or custom from the drop down menu. Orca will use this fluid property to calculate the hydrostatics of your model.

 

Equilibrium Warning Thresholds

When computing free-float hydrostatics (Weight is specified), Orca3D will give a warning if the equilibrium flotation condition results in a heel or trim greater than the threshold value. While this may be a valid equilibrium, it may not be the one that was expected. While the Heel and Trim values for the resultant flotation condition are shown in the report, this warning is an extra reminder to view the details of the condition. See Hydrostatics Output for more information on equilibrium flotation conditions.

 

 

Meshing Tab

 

Orca Mesh Parameters

Edit the Orca Mesh Parameters to change how Rhino computes the Orca mesh for use in hydrostatics calculations (including real-time hydrostatics) and for the real-time sections computations. For more accurate hydrostatics you want finer mesh settings (which produces denser meshes and more accurate results), but sometimes you want somewhat coarser settings for the real-time calculations to enhance speed.

The two most important values are the Density and the Max Distance, Edge to Surf. The Density value is a simple control that internally creates values for all of the other settings. All of the other settings can be changed, but won't have an effect until they reach the point where they imply a finer mesh than the Density setting. For example, with the default 10 meter sailboat from the Hull Assistant, if the Density is set to 1, there will be very little change in the mesh until the Max Distance, Edge to Surf gets below about 1 mm.

See Mesh Density Accuracies for examples of how different Density values affect various hydrostatic parameters.

There are three options:

Density: Rhino uses a formula to control how close the polygon edges are to the original surface.  This is a single value, between 0 and 1, that creates values for all of the other settings (although it doesn't display them). If you set one of these other values to something finer, it overrides the value that the Density setting created. Larger values result in a mesh with a higher polygon count.  The default value in Orca3D is 1.0.

 

Max Distance, Edge to Surf: The default value of zero implies that the value created internally by the Density setting will be used. Be careful about specifying too tight of a tolerance here or the Rhino mesher could take a very long time. A value that is about 1/10000th the size of the length of the vessel seems to be a good compromise between speed and accuracy. For example, on a 10 meter sailboat hull, leaving this value at 0 (turning the option off) with a Density of 1 will yield an error in displacement of about 0.17%. Setting it to 1 mm will reduce the error to about 0.16%, and a value of 0.5mm will reduce the error to about 0.05%, but noticeably increases computation time. On a 160 meter ship hull, leaving this value at 0 (turning the option off) with a Density of 1 will yield an error in displacement of about 0.07%. Setting it to 1 cm will reduce the error to about 0.04%.Orca does not currently display the resultant mesh, but since it uses the Rhino mesher you can see the same result by using the Rhino Mesh command which has the same controls.

 

Density: Rhino uses a formula to control how close the polygon edges are to the original surface.  This is a single value, between 0 and 1, that creates values for all of the other settings (although it doesn't display them). If you set one of these other values to something finer, it overrides the value that the Density setting created. Larger values result in a mesh with a higher polygon count.  The default value in Orca3D is 1.0.

 

Maximum Angle: the maximum allowable change between the surface normal at any point and the mesh vertex.  The default value in Orca3D is 0 which turns this option off.

 

Maximum Aspect Ratio: surfaces are initially tessellated with a regular quadrangle mesh and then that mesh is refined.  The initial quad mesh is constructed so that on average, the maximum aspect ratio of the quads is less than or equal to the maximum aspect ratio.  The default value in Orca3D is 0 which turns this option off.

 

Minimum Edge Length: if any edge is shorter than the minimum edge length, no further division of the mesh faces occurs.  The default value in Orca3D is 0.0001 units.

 

Maximum Edge Length: polygons are further divided until all polygon edges are shorter than this value.  The default value in Orca3D is 0, which turns off this option.

 

Max Distance, Edge to Surf: The default value of zero implies that the value created internally by the Density setting will be used. Be careful about specifying too tight of a tolerance here or the Rhino mesher could take a very long time. A value that is about 1/10000th the size of the length of the vessel seems to be a good compromise between speed and accuracy. For example, on a 10 meter sailboat hull, leaving this value at 0 (turning the option off) with a Density of 1 will yield an error in displacement of about 0.17%. Setting it to 1 mm will reduce the error to about 0.16%, and a value of 0.5mm will reduce the error to about 0.05%, but noticeably increases computation time. On a 160 meter ship hull, leaving this value at 0 (turning the option off) with a Density of 1 will yield an error in displacement of about 0.07%. Setting it to 1 cm will reduce the error to about 0.04%.Orca does not currently display the resultant mesh, but since it uses the Rhino mesher you can see the same result by using the Rhino Mesh command which has the same controls.

 

Minimum Initial Grid Quads: the number of quadrangles per surface in the initial mesh grid.  The default value in Orca3D is 0 which turns this option off.

 

Refine Mesh: after its initial meshing, Rhino uses a recursive process to refine the mesh until it meets the criteria defined by maximum angle, minimum edge length, maximum edge length, and maximum distance, edge to surface options.  The default value in Orca3D is true.

 

Jagged Seams: all surfaces mesh independently and Rhino does not stitch the edges of joined surfaces edges together.  The default value in Orca3D is false, which means watertight meshes are created.

 

Simple Planes: all planar surfaces are meshed by meshing the surface edges and then filling the area bounded by the edges with triangles.  If simple planes is true, the settings, except jagged seams, are ignored for planar surfaces and the planar surface is meshed with as few polygons as possible.  The default fault in Orca 3D is true.