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Open Inventor Release 2024.1.3
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Open Inventor Release 2024.1.3
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Geometric shape formed by extruding a 2D cross section along a 3D spine.
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#include <Inventor/nodes/SoExtrusion.h>
Inheritance diagram for SoExtrusion:Public Member Functions | |
| virtual SoType | getTypeId () const |
| Returns the type identifier for this specific instance. | |
| SoExtrusion () | |
| Constructor. | |
| Public Member Functions inherited from SoShape | |
| virtual SbBool | affectsState () const |
| Overrides default method on SoNode. | |
| ShapeType | getShapeType () |
| Gets the current shape Full Scene Antialiasing type. | |
| Public Member Functions inherited from SoNode | |
| virtual void | setOverride (const SbBool state) |
| Turns the override flag on or off. | |
| virtual SbBool | isOverride () const |
| Returns the state of the override flag. | |
| virtual SoNode * | copy (SbBool copyConnections=FALSE) const |
| Creates and returns an exact copy of the node. | |
| virtual void | touch () |
| Marks an instance as modified, simulating a change to it. | |
| Public Member Functions inherited from SoFieldContainer | |
| void | setToDefaults () |
| Sets all fields in this object to their default values. | |
| SbBool | hasDefaultValues () const |
| Returns TRUE if all of the object's fields have their default values. | |
| SbBool | fieldsAreEqual (const SoFieldContainer *fc) const |
| Returns TRUE if this object's fields are exactly equal to fc's fields. | |
| void | copyFieldValues (const SoFieldContainer *fc, SbBool copyConnections=FALSE) |
| Copies the contents of fc's fields into this object's fields. | |
| SoNONUNICODE SbBool | set (const char *fieldDataString) |
| Sets one or more fields in this object to the values specified in the given string, which should be a string in the Open Inventor file format. | |
| SbBool | set (const SbString &fieldDataString) |
| Sets one or more fields in this object to the values specified in the given string, which should be a string in the Open Inventor file format. | |
| void | get (SbString &fieldDataString) |
| Returns the values of the fields of this object in the Open Inventor ASCII file format in the given string. | |
| virtual int | getFields (SoFieldList &list) const |
| Appends references to all of this object's fields to resultList, and returns the number of fields appended. | |
| virtual int | getAllFields (SoFieldList &list) const |
| Returns a list of fields, including the eventIn's and eventOut's. | |
| virtual SoField * | getField (const SbName &fieldName) const |
| Returns a the field of this object whose name is fieldName. | |
| virtual SoField * | getEventIn (const SbName &fieldName) const |
| Returns a the eventIn with the given name. | |
| virtual SoField * | getEventOut (const SbName &fieldName) const |
| Returns the eventOut with the given name. | |
| SbBool | getFieldName (const SoField *field, SbName &fieldName) const |
| Returns the name of the given field in the fieldName argument. | |
| SbBool | enableNotify (SbBool flag) |
| Notification at this Field Container is enabled (if flag == TRUE) or disabled (if flag == FALSE). | |
| SbBool | isNotifyEnabled () const |
| Notification is the process of telling interested objects that this object has changed. | |
| virtual void | setUserData (void *data) |
| Sets application data. | |
| void * | getUserData (void) const |
| Gets user application data. | |
| Public Member Functions inherited from SoBase | |
| virtual SbName | getName () const |
| Returns the name of an instance. | |
| virtual void | setName (const SbName &name) |
| Sets the name of an instance. | |
| void | setSynchronizable (const bool b) |
| Sets this to be a ScaleViz synchronizable object. | |
| bool | isSynchronizable () const |
| Gets the ScaleViz synchronizable state of this object. | |
| Public Member Functions inherited from SoRefCounter | |
| void | ref () const |
| Adds a reference to an instance. | |
| void | unref () const |
| Removes a reference from an instance. | |
| void | unrefNoDelete () const |
| unrefNoDelete() should be called when it is desired to decrement the reference count, but not delete the instance if this brings the reference count to zero. | |
| int | getRefCount () const |
| Returns current reference count. | |
| void | lock () const |
| lock this instance. | |
| void | unlock () const |
| unlock this instance. | |
| Public Member Functions inherited from SoTypedObject | |
| SbBool | isOfType (const SoType &type) const |
| Returns TRUE if this object is of the type specified in type or is derived from that type. | |
| template<typename TypedObjectClass > | |
| SbBool | isOfType () const |
| Returns TRUE if this object is of the type of class TypedObjectClass or is derived from that class. | |
Static Public Member Functions | |
| static SoType | getClassTypeId () |
| Returns the type identifier for this class. | |
| Static Public Member Functions inherited from SoBaseExtrusion | |
| static SoType | getClassTypeId () |
| Returns the type identifier for this class. | |
| Static Public Member Functions inherited from SoShape | |
| static SoType | getClassTypeId () |
| Returns the type identifier for this class. | |
| static SbBool | isPrimitiveRestartAvailable (SoState *state=NULL) |
| Returns TRUE if the primitive restart feature is available. | |
| Static Public Member Functions inherited from SoNode | |
| static SoType | getClassTypeId () |
| Returns the type identifier for this class. | |
| static SoNode * | getByName (const SbName &name) |
| A node's name can be set using SoBase::setName(). | |
| static int | getByName (const SbName &name, SoNodeList &list) |
| A node's name can be set using SoBase::setName(). | |
| Static Public Member Functions inherited from SoFieldContainer | |
| static SoType | getClassTypeId () |
| Returns the type of this class. | |
| Static Public Member Functions inherited from SoBase | |
| static SoType | getClassTypeId () |
| Returns type identifier for this class. | |
| Static Public Member Functions inherited from SoTypedObject | |
| static SoType | getClassTypeId () |
| Returns the type identifier for this class. | |
Public Attributes | |
| SoMFVec2f | crossSection |
| The shape that will be extruded, defined by a 2D piecewise linear curve in the XZ plane (described as a series of connected vertices). | |
| SoMFRotation | orientation |
| The cross-section curve is rotated by this value relative to a local reference system with origin at the current spine point and X / Z axes in the plane containing the cross-section curve. | |
| SoMFVec2f | scale |
| The cross-section curve is scaled by this value on the X and Z axes. | |
| Public Attributes inherited from SoBaseExtrusion | |
| SoSFBool | beginCap |
| If TRUE, begin planar cap surfaces generated. | |
| SoSFBool | endCap |
| If TRUE, end planar cap surfaces generated. | |
| SoMFVec3f | spine |
| Spine points. | |
| SoSFEnum | scaleMode |
| Scaling behavior of the extrusion. | |
| SoSFEnum | extrusionMode |
| Construction behavior of the extrusion. | |
| Public Attributes inherited from SoShape | |
| SoSFBool | boundingBoxIgnoring |
| Whether to ignore this node during bounding box traversal. | |
Additional Inherited Members | |
| Public Types inherited from SoBaseExtrusion | |
| enum | ScaleMode { DEFAULT , SPINE_ONLY , SECTION_ONLY , NONE } |
| enum | ExtrusionMode { SMOOTH = 0 , BASIC = 1 , SMOOTH_WITHOUT_SELF_INTERSECTIONS = 2 } |
| Public Types inherited from SoShape | |
| enum | ShapeType { POINTS , LINES , POLYGONS , TEXT } |
| Basic type for antialiased rendering for this shape (Do not consider the SoDrawStyle property currently in the state). More... | |
Geometric shape formed by extruding a 2D cross section along a 3D spine.
The SoExtrusion node specifies geometric shapes based on a two-dimensional cross section extruded along a three-dimensional spine. The cross section can be scaled and rotated at each spine point to produce a wide variety of shapes.
An SoExtrusion is defined by:
Shapes are constructed as follows - For each point in the spine, the cross-section curve, which is a curve in the XZ plane, is scaled about the origin by the corresponding scale parameter (first value scales in X, second value scales in Z), rotated about the origin by the corresponding orientation parameter and translated by the vector defined by the corresponding vertex of the spine curve. Each instance of the cross-section is then connected to the following instance.
The scaleMode field 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:
A transformed cross section is found for each joint (that is, at each vertex of the spine curve, where segments of the extrusion connect), and the joints and segments are connected to form the surface. No check is made for self-penetration. Each transformed cross section is determined as follows:
For all points other than the first or last: The tangent for spine[ i ] is found by normalizing the vector defined by (spine[ i +1] - spine[ i -1]).
If the spine curve is closed: The first and last points need to have the same tangent. This tangent is found as above, but using the points spine[0] for spine[ i ], spine[1] for spine[ i +1] and spine[ n -2] for spine[ i -1], where spine[ n -2] is the next to last point on the curve. The last point in the curve, spine[ n -1], is the same as the first, spine[0].
If the spine curve is not closed: The tangent used for the first point is just the direction from spine[0] to spine[1], and the tangent used for the last is the direction from spine[ n -2] to spine[ n -1].
In the simple case where the spine curve is flat in the XY plane, these rotations are all just rotations about the Z axis. In the more general case where the spine curve is any 3D curve, you need to find the destinations for all 3 of the local X, Y, and Z axes so you can completely specify the rotation. The Z axis is found by taking the cross product of:
(spine[ i -1] - spine[ i ]) and (spine[ i +1] - spine[ i ]).
If the three points are collinear then this value is zero, so take the value from the previous point. Once you have the Z axis (from the cross product) and the Y axis (from the approximate tangent), calculate the X axis as the cross product of the Y and Z axes.
Surfaces of revolution: If the cross section is an approximation of a circle and the spine is straight, then the SoExtrusion is equivalent to a surface of revolution, where the scale parameters define the size of the cross section along the spine.
Cookie-cutter extrusions: If the scale is 1, 1 and the spine is straight, then the cross section acts like a cookie cutter, with the thickness of the cookie equal to the length of the spine.
Bend/twist/taper objects: These shapes are the result of using all fields. The spine curve bends the extruded shape defined by the cross section, the orientation parameters twist it around the spine, and the scale parameters taper it (by scaling about the spine).
SoExtrusion has three parts: the sides, the beginCap (the surface at the initial end of the spine) and the endCap (the surface at the final end of the spine). The caps have an associated SFBool field that indicates whether it exists (TRUE) or doesn't exist (FALSE).
When the beginCap or endCap fields are specified as TRUE, planar cap surfaces will be generated regardless of whether the crossSection is a closed curve. (If crossSection isn't a closed curve, the caps are generated as if it were – equivalent to adding a final point to crossSection that's equal to the initial point. Note that an open surface can still have a cap, resulting (for a simple case) in a shape something like a soda can sliced in half vertically.) These surfaces are generated even if spine is also a closed curve. If a field value is FALSE, the corresponding cap is not generated.
SoExtrusion automatically generates its own normals. Orientation of the normals is determined by the vertex ordering of the quads generated by SoExtrusion. The vertex ordering is in turn determined by the crossSection curve. If the crossSection is counterclockwise when viewed from the +Y axis, then the polygons will have counterclockwise ordering when viewed from 'outside' of the shape (and vice versa for clockwise ordered crossSection curves).
Texture coordinates are automatically generated by extrusions. Textures are mapped so that the coordinates range in the U direction from 0 to 1 along the crossSection curve (with 0 corresponding to the first point in crossSection and 1 to the last) and in the V direction from 0 to 1 along the spine curve (again with 0 corresponding to the first listed spine point and 1 to the last). When crossSection is closed, the texture has a seam that follows the line traced by the crossSection's start/end point as it travels along the spine. If the endCap and/or beginCap exist, the crossSection curve is uniformly scaled and translated so that the largest dimension of the cross-section (X or Z) produces texture coordinates that range from 0.0 to 1.0. The beginCap and endCap textures' S and T directions correspond to the X and Z directions in which the crossSection coordinates are defined.
Also 3D texture coordinates are automatically generated, in a similar way to 2D textures.
NOTE: If your extrusion appears to twist unexpectedly, try setting environment variable OIV_EXTRUSION_EPSILON to a value slightly smaller number than the default, which is .998.
NOTE: If your crossSection is not convex, you must use a SoShapeHints and set the faceType field to UNKNOWN_FACE_TYPE.
| beginCap | TRUE |
| endCap | TRUE |
| spine | [ 0 0 0, 0 1 0 ] |
| scaleMode | DEFAULT |
| crossSection | [ 1 1, 1 -1, -1 -1, -1 1, 1 1 ] |
| orientation | 0 0 1 0 |
| scale | 1 1 |
Definition at line 230 of file SoExtrusion.h.
| SoExtrusion::SoExtrusion | ( | ) |
Constructor.
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static |
Returns the type identifier for this class.
|
virtual |
Returns the type identifier for this specific instance.
Reimplemented from SoBaseExtrusion.
| SoMFVec2f SoExtrusion::crossSection |
The shape that will be extruded, defined by a 2D piecewise linear curve in the XZ plane (described as a series of connected vertices).
Default is a square [ 1 1, 1 -1, -1 -1, -1 1, 1 1 ].
Definition at line 244 of file SoExtrusion.h.
| SoMFRotation SoExtrusion::orientation |
The cross-section curve is rotated by this value relative to a local reference system with origin at the current spine point and X / Z axes in the plane containing the cross-section curve.
If one value is specified it applies to every spine point, else there should be as many values as there are points in the spine. Default is no rotation.
Definition at line 253 of file SoExtrusion.h.
| SoMFVec2f SoExtrusion::scale |
The cross-section curve is scaled by this value on the X and Z axes.
If one value is specified it applies to every spine point, else there should be as many values as there are points in the spine. All scale values must be > 0. Default is (1,1) meaning no scaling.
Definition at line 261 of file SoExtrusion.h.
1.9.8 