pfCircle3d(3pf) OpenGL Performer 3.2.2 libpf C Reference Pages
NAME
pfGetCircle3dClassType, pfNewCircle3d, pfCircle3dRadius,
pfGetCircle3dRadius, pfCircle3dEvalPt, pfCircle3dEvalTan,
pfCircle3dEvalNorm - A three-dimensional parametric circle
FUNCTION SPECIFICATION
#include <Performer/pf.h>
pfType * pfGetCircle3dClassType(void);
pfCircle3d * pfNewCircle3d(void *arena);
void pfCircle3dRadius(pfCircle3d *circle, pfReal radius);
pfReal pfGetCircle3dRadius(pfCircle3d *circle);
void pfCircle3dEvalPt(pfCircle3d *circle, pfReal u, pfReal v,
pfVec3 &pnt);
void pfCircle3dEvalTan(pfCircle3d *circle, pfReal u, pfReal v,
pfVec3 &tan);
void pfCircle3dEvalNorm(pfCircle3d *circle, pfReal u, pfReal v,
pfVec3 &norm);
PARENT CLASS FUNCTIONS
The OpenGL Performer class pfCircle3d is derived from the parent class
pfCurve3d, so each of these member functions of class pfCurve3d are also
directly usable with objects of class pfCircle3d. Casting an object of
class pfCircle3d to an object of class pfCurve3d is taken care of
automatically. This is also true for casts to objects of ancestor
classes of class pfCurve3d.
pfReal pfGetCurve3dBeginT(pfCurve3d *curve);
pfReal pfGetCurve3dEndT(pfCurve3d *curve);
void pfCurve3dSetClosed(pfCurve3d *curve, int loopVal);
int pfGetCurve3dClosed(pfCurve3d *curve);
void pfCurve3dClosedTol(pfCurve3d *curve, pfReal tol);
pfReal pfGetCurve3dClosedTol(pfCurve3d *curve);
void pfCurve3dEvalPt(pfCurve3d *curve, pfReal t, pfVec3 &pt);
void pfCurve3dEvalTan(pfCurve3d *curve, pfReal t, pfVec3 &pt);
void pfCurve3dEvalNorm(pfCurve3d *curve, pfReal t, pfVec3 &pt);
Since the class pfCurve3d is itself derived from the parent class pfRep,
objects of class pfCircle3d can also be used with these functions
designed for objects of class pfRep.
void pfRepOrigin(pfRep *rep, const pfVec3 origin);
void pfRepOrient(pfRep *rep, const pfMatrix mat);
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pfCircle3d(3pf) OpenGL Performer 3.2.2 libpf C Reference Pages
void pfGetRepOrigin(pfRep *rep, pfVec3* origin);
void pfGetRepOrient(pfRep *rep, pfMatrix *mat);
Since the class pfRep is itself derived from the parent class pfGeode,
objects of class pfCircle3d can also be used with these functions
designed for objects of class pfGeode.
int pfAddGSet(pfGeode* geode, pfGeoSet* gset);
int pfRemoveGSet(pfGeode* geode, pfGeoSet* gset);
int pfInsertGSet(pfGeode* geode, int index, pfGeoSet* gset);
int pfReplaceGSet(pfGeode* geode, pfGeoSet* old, pfGeoSet* new);
pfGeoSet * pfGetGSet(const pfGeode* geode, int index);
int pfGetNumGSets(const pfGeode* geode);
Since the class pfGeode is itself derived from the parent class pfNode,
objects of class pfCircle3d can also be used with these functions
designed for objects of class pfNode.
pfGroup * pfGetParent(const pfNode *node, int i);
int pfGetNumParents(const pfNode *node);
void pfNodeBSphere(pfNode *node, pfSphere *bsph, int mode);
int pfGetNodeBSphere(pfNode *node, pfSphere *bsph);
pfNode* pfClone(pfNode *node, int mode);
pfNode* pfBufferClone(pfNode *node, int mode, pfBuffer *buf);
int pfFlatten(pfNode *node, int mode);
int pfNodeName(pfNode *node, const char *name);
const char * pfGetNodeName(const pfNode *node);
pfNode* pfFindNode(pfNode *node, const char *pathName,
pfType *type);
pfNode* pfLookupNode(const char *name, pfType* type);
int pfNodeIsectSegs(pfNode *node, pfSegSet *segSet,
pfHit **hits[]);
void pfNodeTravMask(pfNode *node, int which, uint mask,
int setMode, int bitOp);
uint pfGetNodeTravMask(const pfNode *node, int which);
void pfNodeTravFuncs(pfNode* node, int which,
pfNodeTravFuncType pre, pfNodeTravFuncType post);
void pfGetNodeTravFuncs(const pfNode* node, int which,
pfNodeTravFuncType *pre, pfNodeTravFuncType *post);
void pfNodeTravData(pfNode *node, int which, void *data);
void * pfGetNodeTravData(const pfNode *node, int which);
void pfNodeTravMode(pfNode* node, int which, int mode,
int val);
int pfGetNodeTravMode(const pfNode* node, int which,
int mode);
Since the class pfNode is itself derived from the parent class pfObject,
objects of class pfCircle3d can also be used with these functions
designed for objects of class pfObject.
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void pfUserDataSlot(pfObject *obj, int slot, void *data);
void pfUserData(pfObject *obj, void *data);
void* pfGetUserDataSlot(pfObject *obj, int slot);
void* pfGetUserData(pfObject *obj);
int pfGetNumUserData(pfObject *obj);
int pfGetNamedUserDataSlot(const char *name);
const char* pfGetUserDataSlotName(int slot);
int pfGetNumNamedUserDataSlots(void);
int pfDeleteGLHandle(pfObject *obj);
Since the class pfObject is itself derived from the parent class
pfMemory, objects of class pfCircle3d can also be used with these
functions designed for objects of class pfMemory.
pfType * pfGetType(const void *ptr);
int pfIsOfType(const void *ptr, pfType *type);
int pfIsExactType(const void *ptr, pfType *type);
const char * pfGetTypeName(const void *ptr);
int pfRef(void *ptr);
int pfUnref(void *ptr);
int pfUnrefDelete(void *ptr);
int pfUnrefGetRef(void *ptr);
int pfGetRef(const void *ptr);
int pfCopy(void *dst, void *src);
int pfDelete(void *ptr);
int pfIsFluxed(void *ptr);
int pfCompare(const void *ptr1, const void *ptr2);
void pfPrint(const void *ptr, uint which, uint verbose,
FILE *file);
void * pfGetArena(void *ptr);
DESCRIPTION
pfCircle3d defines a two three circle parametrized on t:
x(t) = radius * cos(t);
y(t) = radius * sin(t);
z(t) = 0.0;
The default domain is [0, 2*pi].
The circle is subject to rotation and translation by the matrix
orientation and vector origin, which are members of the super class
pfRep. If orientation isn't set, evalTan, evalNorm and evalCurv are
functionally calculated. The normal is the vector from the origin to the
poiint on the circle. When orientation is set, evalTan, evalCurv are
calculated by finite difference method which is subject to numerical
errors. The normal could be reversed depending on the direction of the
circle.
pfGetCircle3dClassType returns the pfType* for the class pfCircle3d. The
pfType* returned by pfGetCircle3dClassType is the same as the pfType*
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pfCircle3d(3pf) OpenGL Performer 3.2.2 libpf C Reference Pages
returned by invoking pfGetType on any instance of class pfCircle3d.
Because OpenGL Performer allows subclassing of built-in types, when
decisions are made based on the type of an object, it is usually better
to use pfIsOfType to test if an object is of a type derived from a
Performer type rather than to test for strict equality of the pfType*'s.
pfNewCircle3d creates an instance of an pfCircle3d with radius set to 1.
By default the parametric domain is defined as [0, 2*pi].
pfCircle3dRadius sets the radius of the circle to radius.
pfGetCircle3dRadius returns the value of the circle's radius.
pfCircle3dEvalPt Computes the point on the circle. The result is put in
pnt. Notice that there is a translation by origin, which is the member of
the superclass pfRep.
pfCircle3dEvalTan Computes the derivatives (-r*sin(t), r*cos(t)) and puts
the result in tan.
pfCircle3dEvalNorm Computes the principal normal of the circle and stores
it in norm.
SEE ALSO
pfRep, pfGeode, pfCurve3d
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