sotrianglestripset(3)
NAME
SoTriangleStripSet
SYNOPSIS
#include <Inventor/nodes/SoTriangleStripSet.h> Inherits SoNonIndexedShape.
Detailed Description
The SoTriangleStripSet class is used to render and control non-indexed
triangle strips.
Triangle strips are specified using the numVertices field.
Coordinates, normals, materials and texture coordinates are all fetched
in order from the current state or from the vertexProperty node if set.
(To render triangle strips from vertex indices, use the
SoIndexedTriangleStripSet node.)
The numVertices field may be used for multiple strips, coordinates will
be fetched with a monotonically increasing index from the coordinates
on the traversal state stack (i.e. typically from the last
SoCoordinate3 node encountered during traversal).
For example, if numVertices is set to [3, 4, 5, 3], this node would
specify a triangle from coordinates 0, 1 and 2, a triangle strip from
coordinates 3, 4, 5 and 6, a triangle strip from coordinates 7, 8, 9,
10 and 11 and finally a triangle from coordinates 12, 13, 14.
- Or to put it another way: in a tristrip there will always be two
vertices more than there are triangles. Realize that you are handling
data on the vertex level (not polygon-level), and that the triangles
are laid out like this, given 5 vertices: - 1-----3-----5
/ /
- / /
2-----4 - .fi
- The above figure in scene graph file format:
#Inventor V2.1 ascii- Separator {
Coordinate3 {point [ -2 1 0, -1 -1 0, 0 1 0, 1 -1 0, 2 1 0 ]}TriangleStripSet {numVertices [ 5 ]}
- }
.fi - The scene graph above in a viewer:
- Strips are converted into triangles the way OpenGL does it, of course, so for the dirty details, check out the documentation of OpenGL's GL_TRIANGLE_STRIP primitive rendering type.
- Binding PER_PART (per strip), PER_VERTEX, PER_FACE or OVERALL can be set for material, and normals. The default material binding is OVERALL. The default normal binding is PER_VERTEX.
- FILE FORMAT/DEFAULTS:
TriangleStripSet {vertexProperty NULL
startIndex 0
numVertices -1- }
- See also:
- SoIndexedTriangleStripSet
- Public Member Functions
- virtual SoType getTypeId (void) const
SoTriangleStripSet (void)
virtual void GLRender (SoGLRenderAction *action) virtual void getPrimitiveCount (SoGetPrimitiveCountAction *action) virtual SbBool generateDefaultNormals (SoState *state, SoNormalBundle*nb) - Static Public Member Functions
- static SoType getClassTypeId (void) static void initClass (void)
- Public Attributes
- SoMFInt32 numVertices
- Protected Member Functions
- virtual const SoFieldData * getFieldData (void) const
virtual ~SoTriangleStripSet ()
virtual void generatePrimitives (SoAction *action) virtual void computeBBox (SoAction *action, SbBox3f &box, SbVec3f¢er) - virtual SbBool generateDefaultNormals (SoState *, SoNormalCache *)
- Static Protected Member Functions
- static const SoFieldData ** getFieldDataPtr (void)
Constructor & Destructor Documentation
- SoTriangleStripSet::SoTriangleStripSet (void)
- Constructor.
- SoTriangleStripSet::~SoTriangleStripSet () [protected, virtual]
- Destructor.
- References SoMField::getNum(), and numVertices.
Member Function Documentation
- SoType SoTriangleStripSet::getClassTypeId (void) [static]
- This static method returns the SoType object associated with objects of this class.
- Reimplemented from SoNonIndexedShape.
- SoType SoTriangleStripSet::getTypeId (void) const [virtual]
- Returns the type identification of an object derived from a class
inheriting SoBase. This is used for run-time type checking and 'downward' casting. - Usage example:
void foo(SoNode * node)
{if (node->getTypeId() == SoFile::getClassTypeId()) {SoFile * filenode = (SoFile *)node; // safe downward cast, knows the type}
else if (node->getTypeId().isOfType(SoGroup::getClassTypeId())) {SoGroup * group = (SoGroup *)node; // safe downward cast, knows the type}} - For application programmers wanting to extend the library with new
nodes, engines, nodekits, draggers or others: this method needs to be
overridden in all subclasses. This is typically done as part of setting up the full type system for extension classes, which is usually
accomplished by using the pre-defined macros available through for
instance Inventor/nodes/SoSubNode.h (SO_NODE_INIT_CLASS and
SO_NODE_CONSTRUCTOR for node classes), Inventor/engines/SoSubEngine.h (for engine classes) and so on. - For more information on writing Coin extensions, see the class
documentation of the toplevel superclasses for the various class
groups. - Reimplemented from SoNonIndexedShape.
- const SoFieldData ** SoTriangleStripSet::getFieldDataPtr (void) [static,
- protected]
This API member is considered internal to the library, as it is not likely to be of interest to the application programmer. - Reimplemented from SoNonIndexedShape.
- const SoFieldData * SoTriangleStripSet::getFieldData (void) const
- [protected, virtual]
Returns a pointer to the class-wide field data storage object for this instance. If no fields are present, returns NULL. - Reimplemented from SoNonIndexedShape.
- static void sogl_nits_m3_n3_t1 void SoTriangleStripSet::initClass (void)
- [static]
Sets up initialization for data common to all instances of this class, like submitting necessary information to the Coin type system. - Reimplemented from SoNonIndexedShape.
- Referenced by SoNode::initClasses().
- void SoTriangleStripSet::GLRender (SoGLRenderAction * action) [virtual]
- Action method for the SoGLRenderAction.
- This is called during rendering traversals. Nodes influencing the
rendering state in any way or who wants to throw geometry primitives at OpenGL overrides this method. - Reimplemented from SoShape.
- References SoNonIndexedShape::fixNumVerticesPointers(),
SoVertexShape::generateAndReadLockNormalCache(), SoMField::getNum(),
SoAction::getState(), SoSFNode::getValue(), SoSFInt32::getValue(),
SoMFInt32::getValues(), SoVertexShape::getVertexData(),
SoNode::GLRender(), numVertices, SoState::pop(), SoState::push(),
SoVertexShape::readUnlockNormalCache(),
SoVertexShape::shouldGLRender(), SoNonIndexedShape::startIndex, and
SoVertexShape::vertexProperty. - void SoTriangleStripSet::getPrimitiveCount (SoGetPrimitiveCountAction *
- action) [virtual]
Action method for the SoGetPrimitiveCountAction. - Calculates the number of triangle, line segment and point primitives
for the node and adds these to the counters of the action. - Nodes influencing how geometry nodes calculates their primitive count
also overrides this method to change the relevant state variables. - Reimplemented from SoShape.
- References SoGetPrimitiveCountAction::addNumTriangles(),
SoGetPrimitiveCountAction::canApproximateCount(),
SoNonIndexedShape::fixNumVerticesPointers(), SoMField::getNum(),
SoAction::getState(), SoMFInt32::getValues(), numVertices, and
SoShape::shouldPrimitiveCount(). - SbBool SoTriangleStripSet::generateDefaultNormals (SoState * state,
- SoNormalBundle * bundle) [virtual] This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.
- Subclasses should override this method to generate default normals
using the SoNormalBundle class. TRUE should be returned if normals were generated, FALSE otherwise. - Default method returns FALSE.
- This function is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.
- Reimplemented from SoVertexShape.
- void SoTriangleStripSet::generatePrimitives (SoAction * action) [protected,
- virtual]
The method implements action behavior for shape nodes for
SoCallbackAction. It is invoked from SoShape::callback(). (Subclasses should not override SoNode::callback().) - The subclass implementations uses the convenience methods
SoShape::beginShape(), SoShape::shapeVertex(), and SoShape::endShape(), with SoDetail instances, to pass the primitives making up the shape back to the caller. - Implements SoShape.
- References SoShape::beginShape(), SoNode::doAction(),
SoShape::endShape(), SoNonIndexedShape::fixNumVerticesPointers(),
SoVertexShape::generateAndReadLockNormalCache(), SoMField::getNum(),
SoAction::getState(), SoSFInt32::getValue(), SoSFNode::getValue(),
SoMFInt32::getValues(), SoVertexShape::getVertexData(),
SoFaceDetail::incFaceIndex(), SoFaceDetail::incPartIndex(),
numVertices, SoState::pop(), SoState::push(),
SoVertexShape::readUnlockNormalCache(),
SoPointDetail::setCoordinateIndex(), SoPrimitiveVertex::setDetail(),
SoFaceDetail::setFaceIndex(), SoPrimitiveVertex::setMaterialIndex(),
SoPointDetail::setMaterialIndex(), SoPrimitiveVertex::setNormal(),
SoPointDetail::setNormalIndex(), SoPrimitiveVertex::setPoint(),
SoPointDetail::setTextureCoordIndex(),
SoPrimitiveVertex::setTextureCoords(), SoShape::shapeVertex(),
SoNonIndexedShape::startIndex, and SoVertexShape::vertexProperty. - void SoTriangleStripSet::computeBBox (SoAction * action, SbBox3f & box,
- SbVec3f & center) [protected, virtual] Implemented by SoShape subclasses to let the SoShape superclass know the exact size and weighted center point of the shape's bounding box.
- The bounding box and center point should be calculated and returned in the local coordinate system.
- The method implements action behavior for shape nodes for
SoGetBoundingBoxAction. It is invoked from SoShape::getBoundingBox(). (Subclasses should not override SoNode::getBoundingBox().) - The box parameter sent in is guaranteed to be an empty box, while center is undefined upon function entry.
- Implements SoShape.
- SbBool SoTriangleStripSet::generateDefaultNormals (SoState * state,
- SoNormalCache * cache) [protected, virtual] This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.
- Subclasses should override this method to generate default normals
using the SoNormalCache class. This is more effective than using
SoNormalGenerator. Return TRUE if normals were generated, FALSE
otherwise. - Default method just returns FALSE.
- This function is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.
- Reimplemented from SoVertexShape.
- References SoNonIndexedShape::fixNumVerticesPointers(),
SoMField::getNum(), SoSFInt32::getValue(), SoMFInt32::getValues(),
numVertices, and SoNonIndexedShape::startIndex.
Member Data Documentation
- SoMFInt32 SoTriangleStripSet::numVertices
- Specifies the number of vertices in each triangle strip. The vertices
are fetched from the current coordinate node, or from the
vertexProperty field if present. - Referenced by generateDefaultNormals(), generatePrimitives(),
getPrimitiveCount(), GLRender(), and ~SoTriangleStripSet().
Author
- Generated automatically by Doxygen for Coin from the source code.