mrq/reactphysics3d
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

git-svn-id: https://reactphysics3d.googlecode.com/svn/trunk@93 92aac97c-a6ce-11dd-a772-7fcde58d38e6

Browse Source
This commit is contained in:
chappuis.daniel 2009-02-12 12:37:59 +00:00
parent fe1c482d4b
commit 87627f856d
2 changed files with 39 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

39
sources/reactphysics3d/mathematics/Quaternion.cpp
View File

@ -19,6 +19,7 @@
// Libraries
#include "Quaternion.h"
#include "constants.h"
#include <cassert>
// Namespaces
@ -53,13 +54,41 @@ Quaternion::~Quaternion() {
}
// --- Others functions --- //
// Compute the spherical linear interpolation between two quaternions.
// The t argument has to be such that 0 <= t <= 1
Quaternion slerp(const Quaternion& quaternion1, const Quaternion& quaternion2, double t) {
//TODO : Implement this method
// The t argument has to be such that 0 <= t <= 1.
// TODO : Test this method
Quaternion Quaternion::slerp(const Quaternion& quaternion1, const Quaternion& quaternion2, double t) {
assert(t >= 0 && t <= 1);
double invert = 1;
// Compute cos(theta) using the quaternion scalar product
double cosineTheta = quaternion1.scalarProduct(quaternion2);
// Take care of the sign of cosineTheta
if (cosineTheta < 0) {
cosineTheta = -cosineTheta;
invert = -1;
}
// Because of precision, if cos(theta) is nearly 1, therefore theta is nearly 0 and we can write
// sin((1-t)*theta) as (1-t) and sin(t*theta) as t
if ((1.0-cosineTheta) < epsilon) {
return quaternion1 * (1-t) + quaternion2 * (t * invert);
}
// Compute the theta angle
double theta = acos(cosineTheta);
// Compute sin(theta)
double sineTheta = sin(theta);
// Compute the two coefficients that are in the spherical linear interpolation formula
double coeff1 = sin((1-t)*theta) / sineTheta;
double coeff2 = sin(t*theta) / sineTheta * invert;
// Compute and return the interpolated quaternion
return quaternion1 * coeff1 + quaternion2 * coeff2;
}

12
sources/reactphysics3d/mathematics/Quaternion.h
View File

@ -61,7 +61,10 @@ class Quaternion
Quaternion getUnit() const throw (MathematicsException); // Return the unit quaternion
Quaternion getConjugate() const; // Return the conjugate quaternion
Quaternion getInverse() const throw (MathematicsException); // Return the inverse of the quaternion
double scalarProduct(const Quaternion& quaternion); // Scalar product between two quaternions
double scalarProduct(const Quaternion& quaternion) const; // Scalar product between two quaternions
static Quaternion slerp(const Quaternion& quaternion1,
const Quaternion& quaternion2, double t); // Compute the spherical linear interpolation between two quaternions
// --- Overloaded operators --- //
Quaternion operator+(const Quaternion& quaternion) const; // Overloaded operator for the addition
@ -165,7 +168,7 @@ inline Quaternion Quaternion::getInverse() const throw(MathematicsException) {
// Scalar product between two quaternions
// TODO : Test for this method
inline double Quaternion::scalarProduct(const Quaternion& quaternion) {
inline double Quaternion::scalarProduct(const Quaternion& quaternion) const {
return (x*quaternion.x + y*quaternion.y + z*quaternion.z + w*quaternion.w);
}
@ -212,11 +215,6 @@ inline bool Quaternion::operator==(const Quaternion& quaternion) const {
return (x == quaternion.x && y == quaternion.y && z == quaternion.z && w == quaternion.w);
}
// --- Others functions --- //
// Compute the spherical linear interpolation between two quaternions
Quaternion slerp(const Quaternion& quaternion1, const Quaternion& quaternion2, double t);
} // End of the ReactPhysics3D namespace
#endif