Vec3 Vec3::random_deviant(const Degrees& angle, const Vec3 up) const {
//Lovingly adapted from ogre
Vec3 new_up = (up == Vec3()) ? perpendicular() : up;
Quaternion q;
kmQuaternionRotationAxisAngle(&q, this, random_gen::random_float(0, 1) * (PI * 2.0));
kmQuaternionMultiplyVec3(&new_up, &q, &new_up);
kmQuaternionRotationAxisAngle(&q, &new_up, Radians(angle).value_);
Vec3 ret;
kmQuaternionMultiplyVec3(&ret, &q, this);
return ret;
}
void Camera::update_following(double dt) {
ActorPtr following_actor = following_actor_.lock();
if(following_actor) {
kmQuaternion actor_rotation = following_actor->absolute_rotation();
kmVec3 actor_position = following_actor->absolute_position();
kmVec3 actor_forward;
kmQuaternionGetForwardVec3RH(&actor_forward, &actor_rotation);
kmQuaternion initial_rotation;
kmQuaternionAssign(&initial_rotation, &rotation_);
float t = ((following_lag_ == 0) ? 1.0 : dt * (1.0 / following_lag_));
kmQuaternionSlerp(&rotation_, &initial_rotation, &actor_rotation, t);
kmVec3 rotated_offset;
kmQuaternionMultiplyVec3(&rotated_offset, &rotation_, &following_offset_);
//kmMat4RotationQuaternion(&new_rotation_matrix, &rotation_);
//kmVec3MultiplyMat4(&rotated_offset, &following_offset_, &new_rotation_matrix);
kmVec3Add(&position_, &rotated_offset, &actor_position);
update_from_parent();
} else {
//The actor was destroyed, so reset
following_actor_ = ActorRef();
}
}
kmVec3* kmQuaternionGetForwardVec3LH(kmVec3* pOut, const kmQuaternion* pIn) {
return kmQuaternionMultiplyVec3(pOut, pIn, &KM_VEC3_POS_Z);
}
kmVec3* kmQuaternionGetRightVec3(kmVec3* pOut, const kmQuaternion* pIn) {
return kmQuaternionMultiplyVec3(pOut, pIn, &KM_VEC3_POS_X);
}
