There are no curves in the select list

You are asked to create curves.

The following tabbed dialog is displayed:

Figure 2:2. Form for creation and modification of seams and butts.

• Curve Name

  The name of the seam/butt, if prefix is left out it will be added. Repetition data is handled.

• Symmetry

  The symmetry of the seam/butt.

• Block Limit

  Set the seam/butt to be a block limit by checking the box.

Figure 2:3. Limit tab of seam/butt dialog.

Give values for limiting box of seam/butt, frame positions are allowed.

The buttons will give a quick setting of the box values:

• Portside

  A portside box will be defined, Ymin = 0.

• Starboard

  A starboard box will be defined, Ymax = 0.

• Any

  A box over CL will be defined.

• Default

  The default box for current session of interactive curved hull will be fetched.

Figure 2:4. Data for principal plane, parallel, and parallel between objects tab.

• Type

  Combo box for defining type of curve to define seam.

  Below values only valid for definition curve by principal plane.

• Axis

  Principal axis for definition plane of seam.

• Coordinate

  Coordinate for definition of plane.

  Below values only valid for definition curve parallel to another curve or a sequence of shell curves.

• Curve name pll

  The name of the curve to use as base for parallel curve or starting curve for making sequence.

• End name pll

  Ending curve for creating a sequence of curves.

• Distance

  Offset distance for making parallel curve, or when in sequence mode, label is number of, which will take the number of curves to create between limiting objects.

• Distance end 2

  If given, or given differently from Distance, then the offset distance will be variable along curve.

• Direction

  If Distance End 2 is used, this field defines the direction used to define end 1 and end 2 of the original curve. This field tells how to interpret "end 1" and "end 2". For example, FOR means that the curve should be thought of as running towards the foremost end of the ship, meaning "end 1" is the aftmost end of the curve and "end 2" is the foremost end.

• Method

  X, Y or Z means that the displacement is made along curves created by intersecting the surface with principal planes perpendicular to the given coordinate axis. Perp means that the curves are created by the intersection of the surface and planes that perpendicular to the original curve in a certain point. Using Perp will produce a developed plate that has a constant distance between the two edges made from the two parallel seams. Used in two directions, this can create a rectangular (or close to rectangular) developed plate.

• Side

  In which direction to move the curve. Only an approximate direction is needed as the displacement is done in the surface. Irrelevant alternatives are automatically excluded from the field list.

• Tolerance

  The tolerance used in measuring the accuracy of the displaced curve created as a spline. This value has to correspond to the accuracy of the surface. The default tolerance is 3 mm.

• Iterations

  Maximum number of iterations used to reach a displaced curve with the accuracy given by Tolerance above. By default the number of iterations are set to 20.

• Excess End 1 & 2

  These fields may be used to temporarily extend the curve at both ends before the parallel move is done. For example, consider a curve in the planar side of the ship, generated in such a way that the curve is sloping so that the aftmost end is lower than the for end. If this curve were to be moved upwards with the Method field set to Perp, the parallel curve would not only move upwards, but also towards the aft end of the ship. The addition of excesses means that it will be possible to create the parallel curve in its full length despite of this fact. Please Note that the original curve will not be affected by the use of excess.

• Approximate plane

  When set, an approximately parallel displacement is done, with the restriction that the resulting curve is planar. In this case only three points are displaced, and then a plane is created using these points. The points are the end points and the midpoint of the original curve intersected with the limiting box.

• Advanced button

  This button will switch user into creating definition curves for the definition data, by general cylinder, by planes other than principal planes and for combination of curves. By using this option the old fashioned style with multiple select for defining the curves will appear and in the end the dialog described in scenario 1 will be shown.