private void updateBodyBitmask(Body body)
{
AABB box = body.getAABB();
int minX = (int)Math.Floor((box.Min.x - mWorldLimits.Min.x) / mWorldGridStep.x);
int maxX = (int)Math.Floor((box.Max.x - mWorldLimits.Min.x) / mWorldGridStep.x);
if (minX < 0)
{
minX = 0;
}
else if (minX > 32)
{
minX = 32;
}
if (maxX < 0)
{
maxX = 0;
}
else if (maxX > 32)
{
maxX = 32;
}
int minY = (int)Math.Floor((box.Min.y - mWorldLimits.Min.y) / mWorldGridStep.y);
int maxY = (int)Math.Floor((box.Max.y - mWorldLimits.Min.y) / mWorldGridStep.y);
if (minY < 0)
{
minY = 0;
}
else if (minY > 32)
{
minY = 32;
}
if (maxY < 0)
{
maxY = 0;
}
else if (maxY > 32)
{
maxY = 32;
}
body.mBitMaskX.clear();
for (int i = minX; i <= maxX; i++)
{
body.mBitMaskX.setOn(i);
}
body.mBitMaskY.clear();
for (int i = minY; i <= maxY; i++)
{
body.mBitMaskY.setOn(i);
}
//Console.WriteLine("Body bitmask: minX{0} maxX{1} minY{2} maxY{3}", minX, maxX, minY, minY, maxY);
}
private void updateBodyBitmask(Body body)
{
AABB box = body.getAABB();
int minX = (int)Math.Floor((box.Min.X - mWorldLimits.Min.X) / mWorldGridStep.X);
int maxX = (int)Math.Floor((box.Max.X - mWorldLimits.Min.X) / mWorldGridStep.X);
if (minX < 0) { minX = 0; } else if (minX > 32) { minX = 32; }
if (maxX < 0) { maxX = 0; } else if (maxX > 32) { maxX = 32; }
int minY = (int)Math.Floor((box.Min.Y - mWorldLimits.Min.Y) / mWorldGridStep.Y);
int maxY = (int)Math.Floor((box.Max.Y - mWorldLimits.Min.Y) / mWorldGridStep.Y);
if (minY < 0) { minY = 0; } else if (minY > 32) { minY = 32; }
if (maxY < 0) { maxY = 0; } else if (maxY > 32) { maxY = 32; }
body.mBitMaskX.clear();
for (int i = minX; i <= maxX; i++)
body.mBitMaskX.setOn(i);
body.mBitMaskY.clear();
for (int i = minY; i <= maxY; i++)
body.mBitMaskY.setOn(i);
//Console.WriteLine("Body bitmask: minX{0} maxX{1} minY{2} maxY{3}", minX, maxX, minY, minY, maxY);
}
private void bodyCollide(Body bA, Body bB, List<BodyCollisionInfo> infoList)
{
int bApmCount = bA.PointMassCount;
int bBpmCount = bB.PointMassCount;
AABB boxB = bB.getAABB();
// check all PointMasses on bodyA for collision against bodyB. if there is a collision, return detailed info.
BodyCollisionInfo infoAway = new BodyCollisionInfo();
BodyCollisionInfo infoSame = new BodyCollisionInfo();
for (int i = 0; i < bApmCount; i++)
{
Vector2 pt = bA.getPointMass(i).Position;
// early out - if this point is outside the bounding box for bodyB, skip it!
if (!boxB.contains(ref pt))
continue;
// early out - if this point is not inside bodyB, skip it!
if (!bB.contains(ref pt))
continue;
int prevPt = (i>0) ? i-1 : bApmCount-1;
int nextPt = (i < bApmCount - 1) ? i + 1 : 0;
Vector2 prev = bA.getPointMass(prevPt).Position;
Vector2 next = bA.getPointMass(nextPt).Position;
// now get the normal for this point. (NOT A UNIT VECTOR)
Vector2 fromPrev = new Vector2();
fromPrev.X = pt.X - prev.X;
fromPrev.Y = pt.Y - prev.Y;
Vector2 toNext = new Vector2();
toNext.X = next.X - pt.X;
toNext.Y = next.Y - pt.Y;
Vector2 ptNorm = new Vector2();
ptNorm.X = fromPrev.X + toNext.X;
ptNorm.Y = fromPrev.Y + toNext.Y;
VectorTools.makePerpendicular(ref ptNorm);
// this point is inside the other body. now check if the edges on either side intersect with and edges on bodyB.
float closestAway = 100000.0f;
float closestSame = 100000.0f;
infoAway.Clear();
infoAway.bodyA = bA;
infoAway.bodyApm = i;
infoAway.bodyB = bB;
infoSame.Clear();
infoSame.bodyA = bA;
infoSame.bodyApm = i;
infoSame.bodyB = bB;
bool found = false;
int b1 = 0;
int b2 = 1;
for (int j = 0; j < bBpmCount; j++)
{
Vector2 hitPt;
Vector2 norm;
float edgeD;
b1 = j;
if (j < bBpmCount - 1)
b2 = j + 1;
else
b2 = 0;
Vector2 pt1 = bB.getPointMass(b1).Position;
Vector2 pt2 = bB.getPointMass(b2).Position;
// quick test of distance to each point on the edge, if both are greater than current mins, we can skip!
float distToA = ((pt1.X - pt.X) * (pt1.X - pt.X)) + ((pt1.Y - pt.Y) * (pt1.Y - pt.Y));
float distToB = ((pt2.X - pt.X) * (pt2.X - pt.X)) + ((pt2.Y - pt.Y) * (pt2.Y - pt.Y));
if ((distToA > closestAway) && (distToA > closestSame) && (distToB > closestAway) && (distToB > closestSame))
continue;
// test against this edge.
float dist = bB.getClosestPointOnEdgeSquared(pt, j, out hitPt, out norm, out edgeD);
// only perform the check if the normal for this edge is facing AWAY from the point normal.
float dot;
//Vector2.Dot(ref ptNorm, ref edgeNorm, out dot);
Vector2.Dot(ref ptNorm, ref norm, out dot);
if (dot <= 0f)
{
if (dist < closestAway)
{
closestAway = dist;
infoAway.bodyBpmA = b1;
infoAway.bodyBpmB = b2;
infoAway.edgeD = edgeD;
infoAway.hitPt = hitPt;
infoAway.normal = norm;
infoAway.penetration = dist;
found = true;
}
}
else
{
if (dist < closestSame)
{
closestSame = dist;
infoSame.bodyBpmA = b1;
infoSame.bodyBpmB = b2;
infoSame.edgeD = edgeD;
infoSame.hitPt = hitPt;
infoSame.normal = norm;
infoSame.penetration = dist;
}
}
}
// we've checked all edges on BodyB. add the collision info to the stack.
if ((found) && (closestAway > mPenetrationThreshold) && (closestSame < closestAway))
{
infoSame.penetration = (float)Math.Sqrt(infoSame.penetration);
infoList.Add(infoSame);
}
else
{
infoAway.penetration = (float)Math.Sqrt(infoAway.penetration);
infoList.Add(infoAway);
}
}
}
private void bodyCollide(Body bA, Body bB, List <BodyCollisionInfo> infoList)
{
int bApmCount = bA.PointMassCount;
int bBpmCount = bB.PointMassCount;
AABB boxB = bB.getAABB();
// check all PointMasses on bodyA for collision against bodyB. if there is a collision, return detailed info.
BodyCollisionInfo infoAway = new BodyCollisionInfo();
BodyCollisionInfo infoSame = new BodyCollisionInfo();
for (int i = 0; i < bApmCount; i++)
{
Vector2 pt = bA.getPointMass(i).Position;
// early out - if this point is outside the bounding box for bodyB, skip it!
if (!boxB.contains(ref pt))
{
continue;
}
// early out - if this point is not inside bodyB, skip it!
if (!bB.contains(ref pt))
{
continue;
}
int prevPt = (i > 0) ? i - 1 : bApmCount - 1;
int nextPt = (i < bApmCount - 1) ? i + 1 : 0;
Vector2 prev = bA.getPointMass(prevPt).Position;
Vector2 next = bA.getPointMass(nextPt).Position;
// now get the normal for this point. (NOT A UNIT VECTOR)
Vector2 fromPrev = new Vector2();
fromPrev.x = pt.x - prev.x;
fromPrev.y = pt.y - prev.y;
Vector2 toNext = new Vector2();
toNext.x = next.x - pt.x;
toNext.y = next.y - pt.y;
Vector2 ptNorm = new Vector2();
ptNorm.x = fromPrev.x + toNext.x;
ptNorm.y = fromPrev.y + toNext.y;
VectorTools.makePerpendicular(ref ptNorm);
// this point is inside the other body. now check if the edges on either side intersect with and edges on bodyB.
float closestAway = 100000.0f;
float closestSame = 100000.0f;
infoAway.Clear();
infoAway.bodyA = bA;
infoAway.bodyApm = i;
infoAway.bodyB = bB;
infoSame.Clear();
infoSame.bodyA = bA;
infoSame.bodyApm = i;
infoSame.bodyB = bB;
bool found = false;
int b1 = 0;
int b2 = 1;
for (int j = 0; j < bBpmCount; j++)
{
Vector2 hitPt;
Vector2 norm;
float edgeD;
b1 = j;
if (j < bBpmCount - 1)
{
b2 = j + 1;
}
else
{
b2 = 0;
}
Vector2 pt1 = bB.getPointMass(b1).Position;
Vector2 pt2 = bB.getPointMass(b2).Position;
// quick test of distance to each point on the edge, if both are greater than current mins, we can skip!
float distToA = ((pt1.x - pt.x) * (pt1.x - pt.x)) + ((pt1.y - pt.y) * (pt1.y - pt.y));
float distToB = ((pt2.x - pt.x) * (pt2.x - pt.x)) + ((pt2.y - pt.y) * (pt2.y - pt.y));
if ((distToA > closestAway) && (distToA > closestSame) && (distToB > closestAway) && (distToB > closestSame))
{
continue;
}
// test against this edge.
float dist = bB.getClosestPointOnEdgeSquared(pt, j, out hitPt, out norm, out edgeD);
// only perform the check if the normal for this edge is facing AWAY from the point normal.
float dot;
//Vector2.Dot(ref ptNorm, ref edgeNorm, out dot);
// Vector2.Dot(ref ptNorm, ref norm, out dot);
dot = Vector2.Dot(ptNorm, norm);
if (dot <= 0f)
{
if (dist < closestAway)
{
closestAway = dist;
infoAway.bodyBpmA = b1;
infoAway.bodyBpmB = b2;
infoAway.edgeD = edgeD;
infoAway.hitPt = hitPt;
infoAway.normal = norm;
infoAway.penetration = dist;
found = true;
}
}
else
{
if (dist < closestSame)
{
closestSame = dist;
infoSame.bodyBpmA = b1;
infoSame.bodyBpmB = b2;
infoSame.edgeD = edgeD;
infoSame.hitPt = hitPt;
infoSame.normal = norm;
infoSame.penetration = dist;
}
}
}
// we've checked all edges on BodyB. add the collision info to the stack.
if ((found) && (closestAway > mPenetrationThreshold) && (closestSame < closestAway))
{
infoSame.penetration = (float)Math.Sqrt(infoSame.penetration);
infoList.Add(infoSame);
}
else
{
infoAway.penetration = (float)Math.Sqrt(infoAway.penetration);
infoList.Add(infoAway);
}
}
}