Package com.luciad.view.lightspeed.editor

Class TLspArcEditor

java.lang.Object
com.luciad.view.lightspeed.editor.ALspEditor
com.luciad.view.lightspeed.editor.TLspArcEditor
All Implemented Interfaces:
ILspEditor
public class TLspArcEditor extends ALspEditor
Enables visual editing of ILcd2DEditableArc objects in an ILspView.

Handles

The arc editor defines the following edit handles for an arc object:
  • Corner point handles: allows the user to edit the corner points of the arc. The user can change the location of these corner points by dragging the corresponding handle. These handles generate MOVE operations, with a HANDLE_IDENTIFIER property and MAJOR_AXIS, MAJOR_AXIS_OPPOSITE, MINOR_AXIS or MINOR_AXIS_OPPOSITE as value.
  • Start and end point handles: allows the user to edit the start and end point of the arc segment. The user can change the location of these points by dragging the corresponding handle. These handles generate MOVE operations, with a HANDLE_IDENTIFIER property and START_POINT or END_POINT as value.
  • Center point handle: allows the user to translate the center of the arc. The user can change the position of the center point by dragging the handle. This handle generates MOVE operations, with a HANDLE_IDENTIFIER property with CENTER as value.
  • Object translation handle: allows the user to translate the arc object. This handle generates MOVE operations, without any additional properties.

The following image clarifies the handle locations: the point and center handles are represented by red points, the green outline indicates the object itself which can be used to activate the object handles.

The handles of a regular arc

Editing

Based on the TLspEditOperation, generated by an edit handle (see description of handles above), this editor performs different edit operations on the associated arc object. The images below illustrate the effect of the different handles. In each image the gray color represents the previous state of the object and the red color represents the edited object:
  • Corner point handles: the editor adjusts the corresponding corner point of the arc, based on the new location of the point handle. The figure below illustrates this behaviour when the start point of the arc is moved (indicated by the arrow)

    Moving a corner point handle of an arc.
  • Start and end point handles: the editor adjusts the start of end point of the arc, based on the new location of the point handle.
  • Center point handle: the editor translates the entire arc. The figure below illustrates this behaviour when moving the center point.

    Moving the center point handle.
  • Object translation handle: the editor translates the entire arc. Note that the behaviour for this handle is identical to the behaviour of the center point handle, with the exception of how the handle is activated

Creation

The creation process of an arc object consists of the following steps:
  1. the first step sets the center of the arc
  2. the second step initializes the major axis of the arc
  3. the third step initializes the minor axis of the arc
  4. the fourth step sets the start point of the arc
  5. the fifth step sets the end point of the arc

The figures below illustrate the creation process. Relevant changes that are new in each step are marked in red:

Setting the center point
Initializing the major axis
Initializing the minor axis
Setting the start point
Setting the end point
Setting the center point Initializing the major axis Initializing the minor axis Setting the start point Setting the end point
Since:
2012.0

  • Constructor Details

    • TLspArcEditor

      public TLspArcEditor()
      Creates a new TLspArcEditor. This constructor does not initialize any state.

  • Method Details

    • canEdit

      public boolean canEdit(TLspEditContext aContext)
      Returns true if super returns true and the given object is an instance of ILcd2DEditableArc.
      Specified by:
      canEdit in interface ILspEditor
      Overrides:
      canEdit in class ALspEditor
      Parameters:
      aContext - provides context information to the editor
      Returns:
      true if the above conditions are met, false otherwise.

    • editImpl

      protected TLspEditOperationResult editImpl(TLspEditOperation aOperation, ELspInteractionStatus aInteractionStatus, TLspEditContext aContext)
      Called by the edit method to edit the given object based on the given edit operation.

      Note that this method does not need to lock the model of the object, this already happens in the edit method.

      By default, this editor can handle the following operations:

      If any of the operations contains the HANDLE_IDENTIFIER property, with a HandleIdentifier as value, then this editor will only perform the operation on that particular point, otherwise it will perform it on the entire object.
      Specified by:
      editImpl in class ALspEditor
      Parameters:
      aOperation - the event that contains the information on how to edit the object
      aInteractionStatus - the interaction status
      aContext - the edit context
      Returns:
      The result of the operation: Whether or not there was success, and whether or not the current handles of the object should be invalidated.

    • getEditHandles

      public List<ALspEditHandle> getEditHandles(TLspEditContext aContext)
      Returns a set of handles for editing the given object.

      These handles will be able to generate edit operations, that are passed to the edit method. As a way to communicate with this method, handles will copy their properties to the edit operation properties. By default this method delegates to the following methods:

      It returns a list containing the handles returned by those methods. These methods are added for convenience, so they can easily be overridden.
      Parameters:
      aContext - provides context information such as the layer for which the object is being edited
      Returns:
      the edit handles to edit the given object, or an empty list if it should not be possible to edit the given object.
      See Also:

    • createObjectTranslationHandle

      protected ALspEditHandle createObjectTranslationHandle(ILcd2DEditableArc aArc, TLspEditContext aContext)
      Creates an edit handle that allows the user to translate the given shape. By default this is a TLspObjectTranslationHandle.
      Parameters:
      aArc - the shape for which the handle is created
      aContext - the current context
      Returns:
      an edit handle or null if no handle is needed

    • createCenterHandle

      protected ALspEditHandle createCenterHandle(ILcd2DEditableArc aArc, TLspEditContext aContext)
      Creates an edit handle that allows the user to translate the given arc by translating its center point. By default this method returns a TLspPointTranslationHandle with a HANDLE_IDENTIFIER user property with CENTER_POINT as value.
      Parameters:
      aArc - the arc for which the handle is created
      aContext - the current context
      Returns:
      an edit handle or null when no handle is needed

    • createMinorAxisHandle

      protected ALspEditHandle createMinorAxisHandle(ILcd2DEditableArc aArc, TLspEditContext aContext)
      Creates an edit handle that allows the user to edit the minor axis of the given arc.

      By default this method returns a handle composed of two TLspPointTranslationHandle "sub-handles" that allow the user to edit the two points that form the arc's minor axis. These points are the ILcdArc.MINOR_RADIUS_CORNER and ILcdArc.MINOR_RADIUS_OPPOSITE_CORNER.

      Parameters:
      aArc - the arc for which the handle is created
      aContext - the current context
      Returns:
      an edit handle or null when no handle is needed

    • createMajorAxisHandle

      protected ALspEditHandle createMajorAxisHandle(ILcd2DEditableArc aArc, TLspEditContext aContext)
      Creates an edit handle that allows the user to edit the major axis of the given arc.

      By default this method returns a handle composed of two TLspPointTranslationHandle "sub-handles" that allow the user to edit the two points that form the arc's major axis. These points are the ILcdArc.MAJOR_RADIUS_CORNER and ILcdArc.MAJOR_RADIUS_OPPOSITE_CORNER.

      Parameters:
      aArc - the arc for which the handle is created
      aContext - the current context
      Returns:
      an edit handle or null when no handle is needed

    • createEndPointHandle

      protected ALspEditHandle createEndPointHandle(ILcd2DEditableArc aArc, TLspEditContext aContext)
      Creates an edit handle that allows the user to edit the given arc by translating its end point. By default this method returns a TLspPointTranslationHandle with a HANDLE_IDENTIFIER user property with END_POINT as value.
      Parameters:
      aArc - the arc for which the handle is created
      aContext - the current context
      Returns:
      an edit handle or null when no handle is needed

    • createStartPointHandle

      protected ALspEditHandle createStartPointHandle(ILcd2DEditableArc aArc, TLspEditContext aContext)
      Creates an edit handle that allows the user to edit the given arc by translating its start point. By default this method returns a TLspPointTranslationHandle with a HANDLE_IDENTIFIER user property with START_POINT as value.
      Parameters:
      aArc - the arc for which the handle is created
      aContext - the current context
      Returns:
      an edit handle or null when no handle is needed

    • getCreateHandle

      public ALspEditHandle getCreateHandle(TLspEditContext aContext)
      Returns a handle that is used to create the given object. The returned handle is used by the controller to initialize the other of the object.

      Typically the returned handle is an instance of ALspCreateHandle which is a specialized handle implementation used for creating an object.

      By default, this method returns an ALspCreateHandle capable of creating an ILcd2DEditableArc, as described in the class javadoc.

      Parameters:
      aContext - provides context information such as the layer for which the object is being created
      Returns:
      an edit handle, or null if creation should not be allowed.
      See Also: