/**
* @brief Create the internal shape used to represent a TSBoxCollider.
**/
public override Physics2D.Shape[] CreateShapes()
{
if (m_Points == null || m_Points.Length == 0)
{
return(null);
}
Physics2D.Vertices v = new Physics2D.Vertices();
for (int index = 0, length = m_Points.Length; index < length; index++)
{
v.Add(m_Points[index]);
}
List <Physics2D.Vertices> convexShapeVs = Physics2D.BayazitDecomposer.ConvexPartition(v);
Physics2D.Shape[] result = new Physics2D.Shape[convexShapeVs.Count];
for (int index = 0, length = result.Length; index < length; index++)
{
result[index] = new Physics2D.PolygonShape(convexShapeVs[index], 1);
}
return(result);
}
/// <summary>
/// Activate the explosion at the specified position.
/// </summary>
/// <param name="pos">The position where the explosion happens </param>
/// <param name="radius">The explosion radius </param>
/// <param name="maxForce">The explosion force at the explosion point (then is inversely proportional to the square of the distance)</param>
/// <returns>A list of bodies and the amount of force that was applied to them.</returns>
public Dictionary <Fixture, TSVector2> Activate(TSVector2 pos, FP radius, FP maxForce)
{
AABB aabb;
aabb.LowerBound = pos + new TSVector2(-radius, -radius);
aabb.UpperBound = pos + new TSVector2(radius, radius);
Fixture[] shapes = new Fixture[MaxShapes];
// More than 5 shapes in an explosion could be possible, but still strange.
Fixture[] containedShapes = new Fixture[5];
bool exit = false;
int shapeCount = 0;
int containedShapeCount = 0;
// Query the world for overlapping shapes.
World.QueryAABB(
fixture =>
{
if (fixture.TestPoint(ref pos))
{
if (IgnoreWhenInsideShape)
{
exit = true;
return(false);
}
containedShapes[containedShapeCount++] = fixture;
}
else
{
shapes[shapeCount++] = fixture;
}
// Continue the query.
return(true);
}, ref aabb);
if (exit)
{
return(new Dictionary <Fixture, TSVector2>());
}
Dictionary <Fixture, TSVector2> exploded = new Dictionary <Fixture, TSVector2>(shapeCount + containedShapeCount);
// Per shape max/min angles for now.
FP[] vals = new FP[shapeCount * 2];
int valIndex = 0;
for (int i = 0; i < shapeCount; ++i)
{
PolygonShape ps;
CircleShape cs = shapes[i].Shape as CircleShape;
if (cs != null)
{
// We create a "diamond" approximation of the circle
Vertices v = new Vertices();
TSVector2 vec = TSVector2.zero + new TSVector2(cs.Radius, 0);
v.Add(vec);
vec = TSVector2.zero + new TSVector2(0, cs.Radius);
v.Add(vec);
vec = TSVector2.zero + new TSVector2(-cs.Radius, cs.Radius);
v.Add(vec);
vec = TSVector2.zero + new TSVector2(0, -cs.Radius);
v.Add(vec);
ps = new PolygonShape(v, 0);
}
else
{
ps = shapes[i].Shape as PolygonShape;
}
if ((shapes[i].Body.BodyType == BodyType.Dynamic) && ps != null)
{
TSVector2 toCentroid = shapes[i].Body.GetWorldPoint(ps.MassData.Centroid) - pos;
FP angleToCentroid = FP.Atan2(toCentroid.y, toCentroid.x);
FP min = FP.MaxValue;
FP max = FP.MinValue;
FP minAbsolute = 0.0f;
FP maxAbsolute = 0.0f;
for (int j = 0; j < ps.Vertices.Count; ++j)
{
TSVector2 toVertex = (shapes[i].Body.GetWorldPoint(ps.Vertices[j]) - pos);
FP newAngle = FP.Atan2(toVertex.y, toVertex.x);
FP diff = (newAngle - angleToCentroid);
diff = (diff - FP.Pi) % (2 * FP.Pi);
// the minus pi is important. It means cutoff for going other direction is at 180 deg where it needs to be
if (diff < 0.0f)
{
diff += 2 * FP.Pi; // correction for not handling negs
}
diff -= FP.Pi;
if (FP.Abs(diff) > FP.Pi)
{
continue; // Something's wrong, point not in shape but exists angle diff > 180
}
if (diff > max)
{
max = diff;
maxAbsolute = newAngle;
}
if (diff < min)
{
min = diff;
minAbsolute = newAngle;
}
}
vals[valIndex] = minAbsolute;
++valIndex;
vals[valIndex] = maxAbsolute;
++valIndex;
}
}
Array.Sort(vals, 0, valIndex, _rdc);
_data.Clear();
bool rayMissed = true;
for (int i = 0; i < valIndex; ++i)
{
Fixture fixture = null;
FP midpt;
int iplus = (i == valIndex - 1 ? 0 : i + 1);
if (vals[i] == vals[iplus])
{
continue;
}
if (i == valIndex - 1)
{
// the single edgecase
midpt = (vals[0] + FP.PiTimes2 + vals[i]);
}
else
{
midpt = (vals[i + 1] + vals[i]);
}
midpt = midpt / 2;
TSVector2 p1 = pos;
TSVector2 p2 = radius * new TSVector2(FP.Cos(midpt), FP.Sin(midpt)) + pos;
// RaycastOne
bool hitClosest = false;
World.RayCast((f, p, n, fr) =>
{
Body body = f.Body;
if (!IsActiveOn(body))
{
return(0);
}
hitClosest = true;
fixture = f;
return(fr);
}, p1, p2);
//draws radius points
if ((hitClosest) && (fixture.Body.BodyType == BodyType.Dynamic))
{
if ((_data.Any()) && (_data.Last().Body == fixture.Body) && (!rayMissed))
{
int laPos = _data.Count - 1;
ShapeData la = _data[laPos];
la.Max = vals[iplus];
_data[laPos] = la;
}
else
{
// make new
ShapeData d;
d.Body = fixture.Body;
d.Min = vals[i];
d.Max = vals[iplus];
_data.Add(d);
}
if ((_data.Count > 1) &&
(i == valIndex - 1) &&
(_data.Last().Body == _data.First().Body) &&
(_data.Last().Max == _data.First().Min))
{
ShapeData fi = _data[0];
fi.Min = _data.Last().Min;
_data.RemoveAt(_data.Count - 1);
_data[0] = fi;
while (_data.First().Min >= _data.First().Max)
{
fi.Min -= FP.PiTimes2;
_data[0] = fi;
}
}
int lastPos = _data.Count - 1;
ShapeData last = _data[lastPos];
while ((_data.Count > 0) &&
(_data.Last().Min >= _data.Last().Max)) // just making sure min<max
{
last.Min = _data.Last().Min - FP.PiTimes2;
_data[lastPos] = last;
}
rayMissed = false;
}
else
{
rayMissed = true; // raycast did not find a shape
}
}
for (int i = 0; i < _data.Count; ++i)
{
if (!IsActiveOn(_data[i].Body))
{
continue;
}
FP arclen = _data[i].Max - _data[i].Min;
FP first = TSMath.Min(MaxEdgeOffset, EdgeRatio * arclen);
int insertedRays = FP.Ceiling((((arclen - 2.0f * first) - (MinRays - 1) * MaxAngle) / MaxAngle)).AsInt();
if (insertedRays < 0)
{
insertedRays = 0;
}
FP offset = (arclen - first * 2.0f) / ((FP)MinRays + insertedRays - 1);
//Note: This loop can go into infinite as it operates on FPs.
//Added FPEquals with a large epsilon.
for (FP j = _data[i].Min + first;
j < _data[i].Max || MathUtils.FPEquals(j, _data[i].Max, 0.0001f);
j += offset)
{
TSVector2 p1 = pos;
TSVector2 p2 = pos + radius * new TSVector2(FP.Cos(j), FP.Sin(j));
TSVector2 hitpoint = TSVector2.zero;
FP minlambda = FP.MaxValue;
List <Fixture> fl = _data[i].Body.FixtureList;
for (int x = 0; x < fl.Count; x++)
{
Fixture f = fl[x];
RayCastInput ri;
ri.Point1 = p1;
ri.Point2 = p2;
ri.MaxFraction = 50f;
RayCastOutput ro;
if (f.RayCast(out ro, ref ri, 0))
{
if (minlambda > ro.Fraction)
{
minlambda = ro.Fraction;
hitpoint = ro.Fraction * p2 + (1 - ro.Fraction) * p1;
}
}
// the force that is to be applied for this particular ray.
// offset is angular coverage. lambda*length of segment is distance.
FP impulse = (arclen / (MinRays + insertedRays)) * maxForce * 180.0f / FP.Pi * (1.0f - TrueSync.TSMath.Min(FP.One, minlambda));
// We Apply the impulse!!!
TSVector2 vectImp = TSVector2.Dot(impulse * new TSVector2(FP.Cos(j), FP.Sin(j)), -ro.Normal) * new TSVector2(FP.Cos(j), FP.Sin(j));
_data[i].Body.ApplyLinearImpulse(ref vectImp, ref hitpoint);
// We gather the fixtures for returning them
if (exploded.ContainsKey(f))
{
exploded[f] += vectImp;
}
else
{
exploded.Add(f, vectImp);
}
if (minlambda > 1.0f)
{
hitpoint = p2;
}
}
}
}
// We check contained shapes
for (int i = 0; i < containedShapeCount; ++i)
{
Fixture fix = containedShapes[i];
if (!IsActiveOn(fix.Body))
{
continue;
}
FP impulse = MinRays * maxForce * 180.0f / FP.Pi;
TSVector2 hitPoint;
CircleShape circShape = fix.Shape as CircleShape;
if (circShape != null)
{
hitPoint = fix.Body.GetWorldPoint(circShape.Position);
}
else
{
PolygonShape shape = fix.Shape as PolygonShape;
hitPoint = fix.Body.GetWorldPoint(shape.MassData.Centroid);
}
TSVector2 vectImp = impulse * (hitPoint - pos);
fix.Body.ApplyLinearImpulse(ref vectImp, ref hitPoint);
if (!exploded.ContainsKey(fix))
{
exploded.Add(fix, vectImp);
}
}
return(exploded);
}
