This group node performs a push (save) of the traversal state before traversing its children and a pop (restore) after traversing them. This isolates the separator's children from the rest of the scene graph. A separator can include lights, cameras, coordinates, normals, bindings, and all other properties. Separators are relatively inexpensive (the push/pop operation is highly optimized), so they can be used freely within scenes.

Caching:

The OIV.Inventor.Nodes.SoSeparator node provides caching of state during bounding box computation. This feature can be explicitly enabled or disabled by setting the OIV.Inventor.Nodes.SoSeparator.boundingBoxCaching field. By default, this field is set to AUTO, which means that Open Inventor decides whether to build a cache based on internal heuristics.

Culling:

Separators can also perform culling during rendering and picking. Culling skips over traversal of the separator's children if they are not going to be rendered or picked, based on the comparison of the separator's bounding box with the current view volume. Culling is controlled by the OIV.Inventor.Nodes.SoSeparator.renderCulling and OIV.Inventor.Nodes.SoSeparator.pickCulling fields. These are also set to AUTO by default; however, render culling can be expensive (and can interfere with render caching), so the AUTO heuristics leave it disabled unless specified otherwise. Note that if renderCulling is ON, the OIV.Inventor.Nodes.SoSeparator will prohibit auto-caching, so that no OIV.Inventor.Nodes.SoSeparator (or other render caching node) above this node in the scene graph will automatically create a render cache.

Fast edit:

The fast editing feature allows you to modify parts of a scene without redrawing the entire scene. For example, you could use it to interactively move a small object in a large scene that takes a long time to redraw. Fast editing must be enabled using OIV.Inventor.Actions.SoGLRenderAction.SetFastEditSavePolicy(OIV.Inventor.Actions.SoGLRenderAction.FastEditSavePolicies, System.Boolean).

The OIV.Inventor.Nodes.SoSeparator.fastEditing field enables fast editing for the sub-graph under the OIV.Inventor.Nodes.SoSeparator. Possible values are DISABLE, KEEP_ZBUFFER, and CLEAR_ZBUFFER. Using KEEP_ZBUFFER means that the fast edit geometry is depth buffered against the other objects in the scene, and using CLEAR_ZBUFFER means that the fast edit geometry will be drawn on top of the other objects of the scene. If several SoSeparators have the CLEAR_ZBUFFER flag set, they are drawn in the order in which they appear in the scene. The last separator in the scene will be topmost on the screen.

Fast edit performance:

• This feature is most efficient when the parts of a scene graph to be fast edited contain a relatively small number of triangles.

• The topmost OIV.Inventor.Nodes.SoSeparator of your scene graph should not enable the fast editing feature. Otherwise, performance will be very poor.

• Currently, the entire viewport is saved and restored during fast editing. Therefore, fast editing performance is linked to the size of the viewport: the larger the viewport, the longer it will take to save and restore it.

Fast edit limitations:

• Hardware: Fast editing performance depends on your graphics hardware and driver. To use the fast editing feature, the ARB_bufferRegion OpenGL extension is required.

• Clip planes: When a fast edit object is moved outside the clip planes limit, fast editing is temporarily disabled and the entire scene is redrawn.

• All fast editing sub-graphs are rendered even if only one fast editing sub-graph has changed.

• Transparency: If the scene contains partially transparent objects, there is a possibility of visual artifacts regardless of what transparency algorithm is used. The fast edit shapes are necessarily rendered on top of the rest of the scene, which may not be the order required for correct transparency.

• Stereo rendering: Fast edit is not compatible with stereo rendering. Fast edit is disabled when switching to stereo rendering.

FILE FORMAT/DEFAULT

Separator {

boundingBoxCaching	AUTO
renderCulling	AUTO
pickCulling	AUTO
fastEditing	DISABLE
renderUnitID	-1

}

ACTION BEHAVIOR

OIV.Inventor.Actions.SoGLRenderAction, OIV.Inventor.Actions.SoCallbackAction, OIV.Inventor.Actions.SoGetBoundingBoxAction, OIV.Inventor.Actions.SoGetMatrixAction, OIV.Inventor.Actions.SoHandleEventAction, OIV.Inventor.Actions.SoRayPickAction, OIV.Inventor.Actions.SoSearchAction Saves the current traversal state, traverses all children, and restores the previous traversal state. Sets: OIV.Inventor.Elements.SoCacheElement

Reference