void Camera::lookAt( const vec3 &aEyePoint, const vec3 &target )
{
mEyePoint = aEyePoint;
mViewDirection = normalize( target - mEyePoint );
mOrientation = quat( glm::toQuat( alignZAxisWithTarget( -mViewDirection, mWorldUp ) ) );
mModelViewCached = false;
}
Matrix44<T> Matrix44<T>::createRotation( const Vec3<T> &from, const Vec3<T> &to, const Vec3<T> &worldUp )
{
// The goal is to obtain a rotation matrix that takes
// "fromDir" to "toDir". We do this in two steps and
// compose the resulting rotation matrices;
// (a) rotate "fromDir" into the z-axis
// (b) rotate the z-axis into "toDir"
// The from direction must be non-zero; but we allow zero to and up dirs.
if( from.lengthSquared() == 0 ) {
return Matrix44<T>();
}
else {
Matrix44<T> zAxis2FromDir = alignZAxisWithTarget( from, Vec3<T>::yAxis() );
Matrix44<T> fromDir2zAxis = zAxis2FromDir.transposed();
Matrix44<T> zAxis2ToDir = alignZAxisWithTarget( to, worldUp );
return fromDir2zAxis * zAxis2ToDir;
}
}
void Camera::setWorldUp( const vec3 &aWorldUp )
{
mWorldUp = normalize( aWorldUp );
mOrientation = glm::toQuat( alignZAxisWithTarget( -mViewDirection, mWorldUp ) );
mModelViewCached = false;
}