Coin
4.0.3
Coin3D core library

The SbLine class represents a line in 3D space. More...
#include <Inventor/SbLine.h>
Public Member Functions  
SbLine (const SbVec3f &origin, const SbVec3f &point)  
SbLine (void)  
SbVec3f  getClosestPoint (const SbVec3f &point) const 
SbBool  getClosestPoints (const SbLine &line2, SbVec3f &ptOnThis, SbVec3f &ptOnLine2) const 
const SbVec3f &  getDirection (void) const 
const SbVec3f &  getPosition (void) const 
void  print (FILE *file) const 
void  setPosDir (const SbVec3f &position, const SbVec3f &direction) 
void  setValue (const SbVec3f &origin, const SbVec3f &point) 
The SbLine class represents a line in 3D space.
SbLine provides a way of specifying a directed line, through a 3D point (origin) and a vector direction in 3D space.
It is context dependent whether or not an SbLine is considered as a ray extending from the starting point in only one direction, or as a line intersecting the origin point and extending infinitely from it in both directions.
SbLine is used by many other classes in Coin.
SbLine::SbLine  (  void  ) 
The default constructor does nothing. The line will be uninitialized until the first assignment or setValue() call.
Constructor with origin specifying the line origin point, and point specifying another point on the line that is used to determine the line's direction. point should not be the same as origin, as this will lead to the line having a null vector as the direction vector. This will cause division by zero problems in some of the other methods on this class.
Be aware that the direction vector will be normalized and not be the same as point  origin.
Returns the point on the line which is closest to point:
_ Q D SP xx> \  \  \  \  \ x P P = argument point _ SP = line starting point, and D = line direction of this line Q = point to find and return from function
The vector defined by point and the returned point will be normal to the line.
Note that the SbLine instance is considered to be infinite in both directions from its definition point, as far as this function is concerned.
SbBool SbLine::getClosestPoints  (  const SbLine &  line2, 
SbVec3f &  ptOnThis,  
SbVec3f &  ptOnLine2 ) const 
Returns the two closest points on the lines. If the lines are parallel, all points are equally close and we return FALSE
. If the lines are not parallel, the point positions will be stored in ptOnThis and ptOnLine2, and we'll return TRUE
.
Note that both SbLine instances are considered to be infinite in both directions from their definition points, as far as this function is concerned.
Return a vector representing the direction of the line. The direction vector will always be normalized.
Return a vector representing the origin point on the line.
Dump the state of this object to the fp file stream. Only works in debug version of library, method does nothing in an optimized build.
Set position and direction.
Be aware that the direction vector will be normalized and not be the same as provided to this method.
Set new position and direction of the line by specifying line origin and another point on the line that is used to determine the line's direction. point should not be the same as origin, as this will lead to having a null vector as the direction vector. This will cause division by zero problems in some of the other methods on this class.
Be aware that the direction vector will be normalized and not be the same as point  origin.
Method setPosDir(position, direction) should be preferred over a call to setValue(position, position + direction), because the latter causes numerical problems when position has a very large magnitude and direction is a normalized direction vector.