void solveCollision(float dt)
{
// This function detects particles which are crossing boundary of bodies
// and modifies velocities of them so that they will move just in front of
// boundary. This function function also applies the reaction force to
// bodies as precisely as the numerical stability is kept.
FluidAABB aabb = new FluidAABB();
aabb.lowerBound.x = +float.MaxValue;
aabb.lowerBound.y = +float.MaxValue;
aabb.upperBound.x = -float.MaxValue;
aabb.upperBound.y = -float.MaxValue;
for (int i = 0; i < count; i++)
{
FluidParticle fp = particleBuffer [i];
Vector2 p1 = fp.position;
Vector2 p2 = p1 + dt * fp.velocity;
aabb.lowerBound = Vector2.Min(aabb.lowerBound, Vector2.Min(p1, p2));
aabb.upperBound = Vector2.Max(aabb.upperBound, Vector2.Max(p1, p2));
}
SolveCollisionCallback callback = new SolveCollisionCallback(this, dt);
queryAABB(callback, aabb);
}
public bool contains(FluidAABB aabb)
{
bool result = true;
result = result && lowerBound.x <= aabb.lowerBound.x;
result = result && lowerBound.y <= aabb.lowerBound.y;
result = result && aabb.upperBound.x <= upperBound.x;
result = result && aabb.upperBound.y <= upperBound.y;
return(result);
}
public override FluidAABB getAABB()
{
FluidAABB aabb = new FluidAABB();
aabb.lowerBound.x = transform.position.x - radius;
aabb.lowerBound.y = transform.position.y - radius;
aabb.upperBound.x = transform.position.x + radius;
aabb.upperBound.y = transform.position.y + radius;
return(aabb);
}
public override FluidAABB getAABB()
{
FluidAABB aabb = new FluidAABB();
aabb.lowerBound.x = +float.MaxValue;
aabb.lowerBound.y = +float.MaxValue;
aabb.upperBound.x = -float.MaxValue;
aabb.upperBound.y = -float.MaxValue;
for (int i = 0; i < vertices.Length; i++)
{
aabb.lowerBound = Vector2.Min(aabb.lowerBound, vertices [i]);
aabb.upperBound = Vector2.Max(aabb.upperBound, vertices [i]);
}
return(aabb);
}
void queryAABB(FluidFixtureParticleQueryCallback callback, FluidAABB aabb)
{
if (iterationIndex == 0)
{
triggerContactBuffer.Clear();
}
for (int i = 0; i < fixtureBuffer.Count; i++)
{
FluidFixtureShape fixture = fixtureBuffer [i];
if (fixture != null)
{
if (fixture.enabled && fixture.gameObject.activeInHierarchy)
{
if (!fixture.isTrigger() || iterationIndex == 0)
{
FluidAABB fixtureAABB = fixture.getAABB();
if (fixtureAABB.isOverlap(aabb))
{
int lowerTag = computeTag(inverseDiameter * fixtureAABB.lowerBound.x - 1,
inverseDiameter * fixtureAABB.upperBound.y + 1);
int upperTag = computeTag(inverseDiameter * fixtureAABB.upperBound.x + 1,
inverseDiameter * fixtureAABB.lowerBound.y - 1);
int beginProxy = 0;
int endProxy = count - 1;
int firstProxy = findLowerBoundProxy(beginProxy, endProxy, lowerTag);
int lastProxy = findUpperBoundProxy(beginProxy, endProxy, upperTag);
for (int j = firstProxy; j < lastProxy; j++)
{
callback.reportFixtureAndParticle(fixture, proxyBuffer [j].fp);
}
}
}
}
}
else
{
// removeFixture(fi
fixtureBuffer.RemoveAt(i);
i--;
}
}
}
public bool isOverlap(FluidAABB b)
{
Vector2 d1, d2;
d1 = b.lowerBound - upperBound;
d2 = lowerBound - b.upperBound;
if (d1.x > 0.0f || d1.y > 0.0f)
{
return(false);
}
if (d2.x > 0.0f || d2.y > 0.0f)
{
return(false);
}
return(true);
}
void computeAABB(out FluidAABB aabb)
{
aabb = new FluidAABB();
aabb.lowerBound.x = +float.MaxValue;
aabb.lowerBound.y = +float.MaxValue;
aabb.upperBound.x = -float.MaxValue;
aabb.upperBound.y = -float.MaxValue;
for (int i = 0; i < count; i++)
{
Vector2 p = particleBuffer [i].position;
aabb.lowerBound = Vector2.Min(aabb.lowerBound, p);
aabb.upperBound = Vector2.Max(aabb.upperBound, p);
}
aabb.lowerBound.x -= particleDiameter;
aabb.lowerBound.y -= particleDiameter;
aabb.upperBound.x += particleDiameter;
aabb.upperBound.y += particleDiameter;
}
public void createParticlesFillShapeForGroup(FluidFixtureShape shape, FluidParticleDef def)
{
float stride = getParticleStride();
FluidAABB aabb = shape.getAABB();
// Color c = def.color;
for (float y = Mathf.Floor(aabb.lowerBound.y / stride) * stride; y < aabb.upperBound.y; y += stride)
{
for (float x = Mathf.Floor(aabb.lowerBound.x / stride) * stride; x < aabb.upperBound.x; x += stride)
{
Vector2 p = new Vector2(x, y);
if (shape.testPoint(p))
{
def.position = p;
// def.color = new Color(Random.Range(0,2),Random.Range(0,2),Random.Range(0,2));
createParticle(def);
}
}
}
// def.color = c;
}
public void combine(FluidAABB aabb1, FluidAABB aabb2)
{
lowerBound = Vector2.Min(aabb1.lowerBound, aabb2.lowerBound);
upperBound = Vector2.Max(aabb1.upperBound, aabb2.upperBound);
}
public void combine(FluidAABB aabb)
{
lowerBound = Vector2.Min(lowerBound, aabb.lowerBound);
upperBound = Vector2.Max(upperBound, aabb.upperBound);
}
