void PhysicsBody::setMass(float mass)
{
if (mass <= 0)
{
return;
}
int oldMass = _mass;
_mass = mass;
_massDefault = false;
// update density
if (_mass == PHYSICS_INFINITY)
{
_density = PHYSICS_INFINITY;
}
else
{
if (_area > 0)
{
_density = _mass / _area;
}else
{
_density = 0;
}
}
// the static body's mass and moment is always infinity
if (_dynamic)
{
updateMass(oldMass, _mass);
}
}
// This must be called at the start of every loop.
void movementStart() {
// Setting motion data:
api.getMyZRState(ZRState);
//api.getOtherZRState(OZRState);
for (int i = 0; i < 3; i++) {
position[i] = ZRState[i];
velocity[i] = ZRState[i + 3];
}
mathVecSubtract(acceleration, velocity, lastVelocity, 3);
updateMass();
lastForceMagnitude = 0.f; // Very important in mass calculation [Positioning in loop included].
}
ZPunctum::ZPunctum()
: m_score(1.0)
{
setColor(255, 255, 0, 255);
setX(-1);
setY(-1);
setZ(-1);
setRadius(2.0);
setMaxIntensity(255);
setMeanIntensity(255);
setSDevOfIntensity(0);
updateVolSize();
updateMass();
}
ZPunctum::ZPunctum(double x, double y, double z, double r)
: m_score(1.0)
{
setColor(255, 255, 0, 255);
setX(x);
setY(y);
setZ(z);
setRadius(r);
setMaxIntensity(255);
setMeanIntensity(255);
setSDevOfIntensity(0);
updateVolSize();
updateMass();
}
void PhysicsBody::addMass(float mass)
{
float oldMass = _mass;
if (mass == PHYSICS_INFINITY)
{
_mass = PHYSICS_INFINITY;
_massDefault = false;
_density = PHYSICS_INFINITY;
}
else if (mass == -PHYSICS_INFINITY)
{
return;
}
else
{
if (_massDefault)
{
_mass = 0;
_massDefault = false;
}
if (_mass + mass > 0)
{
_mass += mass;
}else
{
_mass = MASS_DEFAULT;
_massDefault = true;
}
if (_area > 0)
{
_density = _mass / _area;
}
else
{
_density = 0;
}
}
// the static body's mass and moment is always infinity
if (_dynamic)
{
updateMass(oldMass, _mass);
}
}
void ColaMintBottle::setBottleStatus(BottleStatus aNewStat)
{
switch (aNewStat) {
case UNTRIGGERED:
// allow to set arbitrary 'volume' of the fluid in the bottle
// it doesn't afffect the size, though - magic :-D
theProps.property2Float(Property::MASS_STRING, &theColaAmount);
updateMass();
theSplatterCount = 0;
theBottleStatus = UNTRIGGERED;
break;
case TRIGGERED:
theBottleStatus = TRIGGERED;
theCountdown = 100;
break;
case BLOWING:
theBottleStatus = BLOWING;
break;
case EMPTY:
theBottleStatus = EMPTY;
break;
}
}
void ColaMintBottle::newSplatter(unsigned int aSequenceNr)
{
// the first splatter is to reach 1.5m height, improving to 2.5m with the 20th
// then deteriorating quickly - until none left
//
// for simplicity, we assume that a horizontal bottle has the same
// exit velocity and such...
//
// the opening exit velocity can be calculated using energy: m*g*h = 0.5*m*v*v
// i.e. v = sqrt(2*g*h) <- note that the mass of the splatter is not in there
// so we need a 2nd order equation that starts at (0, 1.5), reaches (20,2.5)
// and then decays until (40, 1.5) again.
// then we use a linear equation for the remainder
//
// h=height, n=splatternumber
// i.e. h = -1/400*n*n + 1/10*n + 1.5
// and from 40 onwards:
// h = 1.5 - 3*(n-40)/220
//
// TODO/FIXME: there is a discontinuity in h' - that can be fixed by calculating
// the point where the extension of h' goes through (150,0) -> for later :-)
std::shared_ptr<ColaSplatter> mySplatterPtr =
ObjectFactory::createChildObject<ColaSplatter>();
// Start position for the splatter is above the opening:
// i.e. (0, +0.59*object height). The magic number 0.59 is "slightly more than 1/2"...
// I figured out the number by experiment
const qreal SPLATTER_START = 0.60;
Position myStartPos = getTempCenter();
myStartPos = myStartPos + Vector(0, SPLATTER_START * getTheHeight());
// we need this 90 degrees because the bottle is modelled vertical,
// not horizontal
myStartPos.angle += PI / 2.0;
// departure velocity
qreal myH;
if (aSequenceNr < 40)
myH = (-1 / 400) * aSequenceNr * aSequenceNr + 0.1 * aSequenceNr + 1.5;
else
myH = 1.5 - 3 * (aSequenceNr - 40) / 220;
// if the expected height is less than 0, we're no longer blowing
if (myH < 0.0)
return;
// note: hardcoded constant for G here, because we're using constants from the
// normal world to calculate it - not related to the G in a alternative world.
// (otherwise, the cola bottle would blow as high on the moon as on earth)
qreal myV = sqrt(2.0 * 9.81 * myH);
const qreal mySplatterMass = 0.015;
mySplatterPtr->setAll(myStartPos, myV, mySplatterMass);
theWorldPtr->addObject(mySplatterPtr);
theColaAmount -= mySplatterMass;
updateMass();
// Small HACK :-)
// if we're out-of-bounds, let's misuse the thrust to limit the velocity...
// this will have two effects:
// 1) the last splatter (giving impulse to a nearly-empty bottle) won't work
// 2) and using thrust in the wrong direction actually limits speed!
if (myStartPos.x > 1.4 * theWorldPtr->getTheWorldWidth() ||
myStartPos.y > 1.4 * theWorldPtr->getTheWorldHeight()) {
if (theThrust > 0)
theThrust = - 0.7;
}
// and don't forget Newton's action = -reaction !!!
qreal myImpulse = mySplatterMass * myV;
// HACK HACK HACK: to improve the "feeling", we help the impulse a bit here...
// The Thrust is actually adjustable as a property
// - default is 2.0 (see createPhysicsObject()).
qreal myAngle = getTempCenter().angle;
Vector myImpulseVector = -theThrust * Vector(-myImpulse * sin(myAngle), myImpulse * cos(myAngle));
theB2BodyPtr->ApplyLinearImpulse(myImpulseVector.toB2Vec2(), myStartPos.toB2Vec2(), true);
}
