Bart/bullet3
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

added two methods to btQuaternion, and add a note that the 'angle' method returns the half angle.

Browse Source 
angleShortestPath and getAngleShortestPath
Thanks to Tully Foote. This fixes issue 379.
This commit is contained in:
erwin.coumans
2013-09-16 19:05:36 +00:00
parent 126fd06ac6
commit 5f5d601ebf
1 changed files with 27 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

28
src/LinearMath/btQuaternion.h
View File

@@ -390,7 +390,7 @@ public:
{
return *this / length();
}
/**@brief Return the angle between this quaternion and the other
/**@brief Return the ***half*** angle between this quaternion and the other
* @param q The other quaternion */
btScalar angle(const btQuaternion& q) const
{
@@ -398,6 +398,19 @@ public:
btAssert(s != btScalar(0.0));
return btAcos(dot(q) / s);
}
/**@brief Return the angle between this quaternion and the other along the shortest path
* @param q The other quaternion */
btScalar angleShortestPath(const btQuaternion& q) const
{
btScalar s = btSqrt(length2() * q.length2());
btAssert(s != btScalar(0.0));
if (dot(q) < 0) // Take care of long angle case see http://en.wikipedia.org/wiki/Slerp
return btAcos(dot(-q) / s) * btScalar(2.0);
else
return btAcos(dot(q) / s) * btScalar(2.0);
}
/**@brief Return the angle of rotation represented by this quaternion */
btScalar getAngle() const
{
@@ -405,6 +418,19 @@ public:
return s;
}
/**@brief Return the angle of rotation represented by this quaternion along the shortest path*/
btScalar getAngleShortestPath() const
{
btScalar s;
if (dot(*this) < 0)
s = btScalar(2.) * btAcos(m_floats[3]);
else
s = btScalar(2.) * btAcos(-m_floats[3]);
return s;
}
/**@brief Return the axis of the rotation represented by this quaternion */
btVector3 getAxis() const
{