public bool BeginContact(Contact contact)
{
Body bodyA = contact.FixtureA.Body;
Body bodyB = contact.FixtureB.Body;
// get the speed of impact between the two bodies
Manifold worldManifold;
contact.GetManifold (out worldManifold);
ManifoldPoint p = worldManifold.Points [0];
Vector2 vA = bodyA.GetLinearVelocityFromLocalPoint (p.LocalPoint);
Vector2 vB = bodyB.GetLinearVelocityFromLocalPoint (p.LocalPoint);
float approachVelocity = Math.Abs (Vector2.Dot (vB - vA, worldManifold.LocalNormal));
//deduct hitpoints from both bodies
ProcessContact (contact, bodyA, approachVelocity);
ProcessContact (contact, bodyB, approachVelocity);
return true;
}
public void Initialize(Contact[] contacts, int count, Body toiBody)
{
_count = count;
_toiBody = toiBody;
if (_constraints.Length < _count)
{
_constraints = new TOIConstraint[Math.Max(_constraints.Length * 2, _count)];
}
for (int i = 0; i < _count; ++i)
{
Contact contact = contacts[i];
Fixture fixtureA = contact.FixtureA;
Fixture fixtureB = contact.FixtureB;
Shape shapeA = fixtureA.Shape;
Shape shapeB = fixtureB.Shape;
float radiusA = shapeA.Radius;
float radiusB = shapeB.Radius;
Body bodyA = fixtureA.Body;
Body bodyB = fixtureB.Body;
Manifold manifold;
contact.GetManifold(out manifold);
Debug.Assert(manifold.PointCount > 0);
TOIConstraint constraint = _constraints[i];
constraint.BodyA = bodyA;
constraint.BodyB = bodyB;
constraint.LocalNormal = manifold.LocalNormal;
constraint.LocalPoint = manifold.LocalPoint;
constraint.Type = manifold.Type;
constraint.PointCount = manifold.PointCount;
constraint.Radius = radiusA + radiusB;
for (int j = 0; j < constraint.PointCount; ++j)
{
constraint.LocalPoints[j] = manifold.Points[j].LocalPoint;
}
_constraints[i] = constraint;
}
}
public void Reset(Contact[] contacts, int contactCount, float impulseRatio)
{
_contacts = contacts;
_constraintCount = contactCount;
// grow the array
if (Constraints == null || Constraints.Length < _constraintCount)
{
Constraints = new ContactConstraint[_constraintCount * 2];
for (int i = 0; i < _constraintCount * 2; i++)
{
Constraints[i] = new ContactConstraint();
}
}
for (int i = 0; i < _constraintCount; ++i)
{
Contact contact = contacts[i];
Fixture fixtureA = contact.FixtureA;
Fixture fixtureB = contact.FixtureB;
Shape shapeA = fixtureA.Shape;
Shape shapeB = fixtureB.Shape;
float radiusA = shapeA.Radius;
float radiusB = shapeB.Radius;
Body bodyA = fixtureA.Body;
Body bodyB = fixtureB.Body;
Manifold manifold;
contact.GetManifold(out manifold);
float friction = Settings.MixFriction(fixtureA.Friction, fixtureB.Friction);
float restitution = Settings.MixRestitution(fixtureA.Restitution, fixtureB.Restitution);
Vector2 vA = bodyA.LinearVelocityInternal;
Vector2 vB = bodyB.LinearVelocityInternal;
float wA = bodyA.AngularVelocityInternal;
float wB = bodyB.AngularVelocityInternal;
Debug.Assert(manifold.PointCount > 0);
WorldManifold worldManifold = new WorldManifold(ref manifold, ref bodyA.Xf, radiusA, ref bodyB.Xf,
radiusB);
ContactConstraint cc = Constraints[i];
cc.BodyA = bodyA;
cc.BodyB = bodyB;
cc.Manifold = manifold;
cc.Normal = worldManifold.Normal;
cc.PointCount = manifold.PointCount;
cc.Friction = friction;
cc.LocalNormal = manifold.LocalNormal;
cc.LocalPoint = manifold.LocalPoint;
cc.Radius = radiusA + radiusB;
cc.Type = manifold.Type;
for (int j = 0; j < cc.PointCount; ++j)
{
ManifoldPoint cp = manifold.Points[j];
ContactConstraintPoint ccp = cc.Points[j];
ccp.NormalImpulse = impulseRatio * cp.NormalImpulse;
ccp.TangentImpulse = impulseRatio * cp.TangentImpulse;
ccp.LocalPoint = cp.LocalPoint;
ccp.rA = worldManifold.Points[j] - bodyA.Sweep.c;
ccp.rB = worldManifold.Points[j] - bodyB.Sweep.c;
#if MATH_OVERLOADS
float rnA = MathUtils.Cross(ccp.rA, cc.Normal);
float rnB = MathUtils.Cross(ccp.rB, cc.Normal);
#else
float rnA = ccp.rA.X * cc.Normal.Y - ccp.rA.Y * cc.Normal.X;
float rnB = ccp.rB.X * cc.Normal.Y - ccp.rB.Y * cc.Normal.X;
#endif
rnA *= rnA;
rnB *= rnB;
float kNormal = bodyA.InvMass + bodyB.InvMass + bodyA.InvI * rnA + bodyB.InvI * rnB;
Debug.Assert(kNormal > Settings.Epsilon);
ccp.NormalMass = 1.0f / kNormal;
#if MATH_OVERLOADS
Vector2 tangent = MathUtils.Cross(cc.Normal, 1.0f);
float rtA = MathUtils.Cross(ccp.rA, tangent);
float rtB = MathUtils.Cross(ccp.rB, tangent);
#else
Vector2 tangent = new Vector2(cc.Normal.Y, -cc.Normal.X);
float rtA = ccp.rA.X * tangent.Y - ccp.rA.Y * tangent.X;
float rtB = ccp.rB.X * tangent.Y - ccp.rB.Y * tangent.X;
#endif
rtA *= rtA;
rtB *= rtB;
float kTangent = bodyA.InvMass + bodyB.InvMass + bodyA.InvI * rtA + bodyB.InvI * rtB;
Debug.Assert(kTangent > Settings.Epsilon);
ccp.TangentMass = 1.0f / kTangent;
// Setup a velocity bias for restitution.
ccp.VelocityBias = 0.0f;
float vRel = Vector2.Dot(cc.Normal,
vB + MathUtils.Cross(wB, ccp.rB) - vA - MathUtils.Cross(wA, ccp.rA));
if (vRel < -Settings.VelocityThreshold)
{
ccp.VelocityBias = -restitution * vRel;
}
}
// If we have two points, then prepare the block solver.
if (cc.PointCount == 2)
{
ContactConstraintPoint ccp1 = cc.Points[0];
ContactConstraintPoint ccp2 = cc.Points[1];
float invMassA = bodyA.InvMass;
float invIA = bodyA.InvI;
float invMassB = bodyB.InvMass;
float invIB = bodyB.InvI;
float rn1A = MathUtils.Cross(ccp1.rA, cc.Normal);
float rn1B = MathUtils.Cross(ccp1.rB, cc.Normal);
float rn2A = MathUtils.Cross(ccp2.rA, cc.Normal);
float rn2B = MathUtils.Cross(ccp2.rB, cc.Normal);
float k11 = invMassA + invMassB + invIA * rn1A * rn1A + invIB * rn1B * rn1B;
float k22 = invMassA + invMassB + invIA * rn2A * rn2A + invIB * rn2B * rn2B;
float k12 = invMassA + invMassB + invIA * rn1A * rn2A + invIB * rn1B * rn2B;
// Ensure a reasonable condition number.
const float k_maxConditionNumber = 100.0f;
if (k11 * k11 < k_maxConditionNumber * (k11 * k22 - k12 * k12))
{
// K is safe to invert.
cc.K = new Mat22(new Vector2(k11, k12), new Vector2(k12, k22));
cc.NormalMass = cc.K.Inverse;
}
else
{
// The constraints are redundant, just use one.
// TODO_ERIN use deepest?
cc.PointCount = 1;
}
}
if (fixtureA.PostSolve != null)
{
fixtureA.PostSolve(cc);
}
if (fixtureB.PostSolve != null)
{
fixtureB.PostSolve(cc);
}
}
}
protected override void PostSolve(Contact contact, ContactConstraint impulse)
{
if (_broke)
{
// The body already broke.
return;
}
// Should the body break?
float maxImpulse = 0.0f;
Manifold manifold;
contact.GetManifold(out manifold);
for (int i = 0; i < manifold.PointCount; ++i)
{
maxImpulse = Math.Max(maxImpulse, impulse.Points[i].NormalImpulse);
}
if (maxImpulse > 40.0f)
{
// Flag the body for breaking.
_break = true;
}
}
private bool PlayerEnemyOnCollision(Fixture fixtureA, Fixture fixtureB, Contact contact)
{
if (!((fixtureB.CollisionFilter.CollisionCategories & (Category)Global.CollisionCategories.Light) == (Category)Global.CollisionCategories.Light)
&& !((fixtureB.CollisionFilter.CollisionCategories & (Category)Global.CollisionCategories.Enemy) == (Category)Global.CollisionCategories.Enemy))
{
Vector2 down = new Vector2(0.0f, 1.0f);
Manifold manifold;
contact.GetManifold(out manifold);
float angle = Math.Abs(Vector2.Dot(manifold.LocalNormal, down));
if (angle > 0.99f)
{
OnGround = true;
groundCache.Add(fixtureB);
}
if (angle < 0.15f && angle > -0.15f)
{
OnWall = true;
}
}
if ((fixtureB.CollisionFilter.CollisionCategories & (Category)Global.CollisionCategories.PlayerBullet) == (Category)Global.CollisionCategories.PlayerBullet)
{
// decrement enemy health
Health -= 50;
}
return true;
}
bool OnCollision(Fixture fixtureA, Fixture fixtureB, Contact contact)
{
Vector2 movementBefore = body.LinearVelocity;
body.LinearVelocity = new Vector2(body.LinearVelocity.X, 0);
Block block=null;
foreach (Entity e in game.entities)
{
if (e is Block)
{
Block b = (Block)e;
if(b.fixture.Equals(fixtureB))
{
block = b;
}
}
}
if (contact.IsTouching())
{
if (isMagnet(fixtureB))
return true;
Manifold colis = new Manifold();
contact.GetManifold(out colis);
Vector2 pColis = colis.LocalNormal;
if (pColis.X == 0 && pColis.Y == 1)
{
onGround = true;
modes = Modes.GROUND;
return true;
}
if (pColis.X != 0 && pColis.Y == 0)
{
collisionRec = getBlockFromFixture(fixtureB);
if (fixtureB.Body.Rotation % 45 != 0)
{
onGround = true;
modes = Modes.GROUND;
return false;
}
if (onGround)
{
modes = Modes.WALL;
return false;
}
float direction = inputState.GetJoyDirection();
float x = (float)Math.Sin(direction);
if (pColis.X > 0)
isWallOnRight = true;
else
isWallOnRight = false;
float xMomentum = 0;
if (movementBefore.Y > 0)
{
xMomentum = Math.Abs(body.LinearVelocity.X * 0.3f);
}
else if (movementBefore.Y < 0)
{
xMomentum = -Math.Abs(body.LinearVelocity.X * 0.8f);
}
XboxInput xbi = (XboxInput)inputState;
if (xbi.getYDirection() < 0 || Keyboard.GetState().IsKeyDown(Keys.Up) || Keyboard.GetState().IsKeyDown(Keys.W))
xMomentum += xbi.getYDirection() * 4f;
else
xMomentum = 0;
body.LinearVelocity = new Vector2(0, body.LinearVelocity.Y + xMomentum);
//body.IgnoreGravity = true;
onGround = true;
onGround = true;
modes = Modes.WALL;
ignoreInput = 2;
return false;
}
}
return true;
}
public static float GetMaxCollisionForce(Contact contact)
{
float maxImpulse = 0.0f;
Manifold manifold;
contact.GetManifold(out manifold);
for (int i = 0; i < manifold.PointCount; ++i)
{
maxImpulse = Math.Max(maxImpulse, manifold.Points[i].NormalImpulse);
}
return maxImpulse;
}
private bool Body_OnCollision(Fixture fixturea, Fixture fixtureb, Contact contact)
{
if (!Convert.ToString(fixtureb.UserData).Equals("wall") && !Convert.ToString(fixtureb.UserData).Contains("ship"))
{
if (fixtureb.Body.IsBullet)
{
String data = Convert.ToString(fixtureb.UserData);
String[] splitdata = data.Split(':');
String shotType = splitdata[0];
int shotEffect = Convert.ToInt32(splitdata[1]);
switch (shotType)
{
case ("standard"):
{
this.damageTaken += (shotEffect / 2);
break;
}
}
}
}
else
{
if (fixedJoint == null && Convert.ToString(fixtureb.UserData).Contains("ship"))
{
Manifold manifold;
contact.GetManifold(out manifold);
fixedJoint = new DistanceJoint(base.mSpriteBody, fixtureb.Body, new Vector2(0, 0), manifold.Points[0].LocalPoint);
fixedJoint.CollideConnected = true;
mworld.AddJoint(fixedJoint);
}
this.contactMade = true;
}
return true;
}
