- All Implemented Interfaces:
public class SoCircularExtrusion extends SoBaseExtrusionGeometric shape formed by extruding a circle along a 3D spine. The
SoCircularExtrusionnode is a geometric shape based on a constant
radiuscircle cross section extruded along a three-dimensional polyline (spine). The circle center lies on the spine and the circle lies on the plane normal to the spine at each point. This is similar to specifying an
SoExtrusionwith a circle cross-section, which is convenient for many applications, but this node has additional advantages because it responds to the
The application can specify the visible portion of the shape along the spine using normalized curvilinear coordinates (activeSection). By default the entire spine is visible.
SoCircularExtrusionrepresentation is dependent on
SoComplexity.value. The shape is always simplified when the
SoComplexityvalue is less than 1. Both the cross section (number of segments used for the circle) and the spine (number of points used for the spine) are affected by the simplification. The simplification algorithm approximates the spine by taking into account its curvature. The cross section circle is approximated by at least 10 points. With a
SoComplexityvalue of 0 the extruded shape has the roughest representation.
Approximately the same geometry could be defined using an
SoExtrusionnode, but that node does not currently respond the
SoComplexityvalue. Likewise the clipping behavior could be obtained using two
SoCircularExtrusionuses less memory when the activeSection is a subset of the full spine. These two features make
SoCircularExtrusionvaluable when a large number of cylindrical objects must be displayed.
scaleModefield (inherited from
SoBaseExtrusion) is used to select the points that will be scaled by the current transformation (for example
SoTransform), if any. Translation and rotation are applied in all cases. The options are:
- DEFAULT : Every point in the generated geometry is scaled.
- SPINE_ONLY : Only the spine points are scaled. The cross section points are not scaled, so the cross section shape is undistorted even is scaling is non-uniform.
- SECTION_ONLY : Only the cross section points are scaled. Not currently implemented.
- NONE :
SoExtrusionignores the scaling state. Not currently implemented.
The spine polyline segments must be C0 continous, that is, the spine must be connected at joints. The following segments may be C1 discontinous but be aware that very narrow angles between consecutive polyline semgments can produce odd results with SMOOTH
extrusionModemodes. This is especially noticeable when the angles between segments are very small with respect to the
radius. In the following images the consecutive points A, B, C in the spine show one of these cases. The problem is at point B whose cross sections are abnormally large.
Spine Wireframe Shaded
Nested Class Summary
Nested Classes Modifier and Type Class Description
Nested classes/interfaces inherited from class com.openinventor.inventor.nodes.SoBaseExtrusion
Nested classes/interfaces inherited from class com.openinventor.inventor.nodes.SoShape
Nested classes/interfaces inherited from class com.openinventor.inventor.nodes.SoNode
Fields Modifier and Type Field Description
activeSectionDefines the visible section of the spine in normalized coordinates.
radiusRadius of the circular cross-section.
spineSimplificationModeDefines the spine simplification behavior of the extrusion.
Fields inherited from class com.openinventor.inventor.nodes.SoBaseExtrusion
beginCap, endCap, extrusionMode, scaleMode, spine
Constructors Constructor Description
Methods inherited from class com.openinventor.inventor.nodes.SoShape
getShapeType, isPrimitiveRestartAvailable, isPrimitiveRestartAvailable
Methods inherited from class com.openinventor.inventor.nodes.SoNode
affectsState, callback, copy, copy, distribute, doAction, getAlternateRep, getBoundingBox, getByName, getMatrix, getPrimitiveCount, getRenderEngineMode, getRenderUnitID, GLRender, GLRenderBelowPath, GLRenderInPath, GLRenderOffPath, grabEventsCleanup, grabEventsSetup, handleEvent, isBoundingBoxIgnoring, isOverride, pick, rayPick, search, setOverride, touch, write
Methods inherited from class com.openinventor.inventor.fields.SoFieldContainer
copyFieldValues, copyFieldValues, enableNotify, fieldsAreEqual, get, getAllFields, getEventIn, getEventOut, getField, getFieldName, hasDefaultValues, isNotifyEnabled, set, setToDefaults
Methods inherited from class com.openinventor.inventor.misc.SoBase
dispose, getName, isDisposable, isSynchronizable, setName, setSynchronizable
public final SoSFFloat radiusRadius of the circular cross-section. The default value is 1.
public final SoSFVec2f activeSectionDefines the visible section of the spine in normalized coordinates. The default is (0,1) meaning that the entire spine is rendered.
public final SoSFEnum<SoCircularExtrusion.SpineSimplificationModes> spineSimplificationModeDefines the spine simplification behavior of the extrusion. . Default is DEFAULT. DEFAULT means spine simplification depends only on geometry. This is appropriate in the typical case where a single material is applied to the entire extrusion. RESPECT_MATERIALS means spine simplification preserves multiple materials (if any) applied to the extrusion. This could reduce rendering performance.