Quaternion interpolate(float t, Quaternion a, Quaternion b)
{
float w = acos(dotQuaternion(normQuaternion(a), normQuaternion(b)));
float s = sin(w);
return addQuaternion(scaleQuaternion(sin((1.0f - t) * w) / s, a),
scaleQuaternion(sin(t * w) / s, b));
}
KartUpdateMessage::KartUpdateMessage()
: Message(Message::MT_KART_INFO)
{
World *world = World::getWorld();
unsigned int num_karts = world->getNumKarts();
// Send the number of karts and for each kart the compressed
// control structure (3 ints) and xyz,hpr (4 floats: quaternion:
allocate(getCharLength()+
num_karts*(KartControl::getLength() + getVec3Length()
+getQuaternionLength()) );
addChar(num_karts);
for(unsigned int i=0; i<num_karts; i++)
{
const Kart* kart = world->getKart(i);
const KartControl& kc=kart->getControls();
kc.serialise(this);
addVec3(kart->getXYZ());
addQuaternion(kart->getRotation());
} // for i
} // KartUpdateMessage
void drawContext::eventHandler(int event, float x, float y)
{
int width = _width, height = _height;
if(_retina){ // x,y for retina are still the same as for non-retina
width /= 2;
height /= 2;
}
_current.set(_scale, _translate, _right, _left,
_bottom, _top, width, height, x, y);
double xx[3] = {1.,0.,0.};
double yy[3] = {0.,1.,0.};
double q[4];
switch(event){
case 0: // finger(s) press the screen
// in this case x and y represent the start point
_start.set(_scale, _translate, _right, _left,
_bottom, _top, width, height, x, y);
_previous.set(_scale, _translate, _right, _left,
_bottom, _top, width, height, x, y);
break;
case 1: // finger move (translate)
// in this case x and y represent the current point
_translate[0] += (_current.wnr[0] - _previous.wnr[0]);
_translate[1] += (_current.wnr[1] - _previous.wnr[1]);
_translate[2] = 0.;
break;
case 2: // fingers move (scale)
// in this case we don't care about previous and current position, x
// represent the scale
_scale[0] = _scale[1] = _scale[2] = x;
_start.recenter(_scale, _translate);
break;
case 3: // fingers move (rotate)
addQuaternion((2. * _previous.win[0] - width) / width,
(height - 2. * _previous.win[1]) / height,
(2. * _current.win[0] - width) / width,
(height - 2. * _current.win[1]) / height);
break;
case 4: // release the finger(s)
// Do nothing ?
break;
case 5: // X view
axis_to_quat(xx, M_PI/2, q);
setQuaternion(q[0], q[1], q[2], q[3]);
break;
case 6: // Y view
axis_to_quat(yy, M_PI/2, q);
setQuaternion(q[0], q[1], q[2], q[3]);
break;
case 7: // Z view
setQuaternion(0., 0., 0., 1.);
break;
default: // all other reset the position
setQuaternion(0., 0., 0., 1.);
for(int i = 0; i < 3; i++){
_translate[i] = 0.;
_scale[i] = 1.;
}
break;
}
_previous.set(_scale, _translate, _right, _left,
_bottom, _top, width, height, x, y);
}