public override bool Equals(object obj)
{
if (obj == null || GetType() != obj.GetType())
{
return(false);
}
BallV b = (BallV)obj;
return(this.position.Equals(b.position) && this.velocity.Equals(b.velocity));
}
public void courseCollision(BallV b)
{
//new collision checking - rolled in for efficiency
Vec2 delta = (this.position.Subtract(b.position));
float r = this.radius + b.radius;
float dist2 = delta.Dot(delta);
//if (dist2 > r * r) return;
float d = delta.GetLength();
//mtd - minimum translation distance to avoid sticking
Vec2 mtd;
if (d != 0.0f)
{
mtd = delta.Multiply(((this.radius + b.radius) - d) / d);
}
else //special, balls are exact overlap
{
d = this.radius + b.radius - 1.0f;
delta = new Vec2(b.radius + this.radius, 0.0f);
mtd = delta.Multiply(((this.radius + b.radius) - d) / d);
}
//inverse mass quantities
float im1 = 1.0f / this.mass;
float im2 = 1.0f / b.mass;
//push-pull apart
this.position = this.position.Add(mtd.Multiply(im1 / (im1 + im2)));
b.position = b.position.Subtract(mtd.Multiply(im2 / (im1 + im2)));
//impact speed
Vec2 v = (this.velocity.Subtract(b.velocity));
float vn = v.Dot(mtd.Normalize());
//intersecting but already receding
if (vn > 0.0f)
{
return;
}
//impulse on collision
float i = (-(1.0f + 0.80f) * vn) / (im1 + im2);
Vec2 impulse = mtd.Multiply(i);
//momentum change
this.velocity = this.velocity.Add(impulse.Multiply(im1));
b.velocity = b.velocity.Subtract(impulse.Multiply(im2));
}
//old collision checking
public bool BallsColliding(BallV b)
{
float xd = position.x - b.position.x;
float yd = position.y - b.position.y;
float sqrDist = (xd * xd) + (yd * yd);
int sumRad = radius + b.radius;
int sqrRad = sumRad * sumRad;
if (sqrDist <= sqrRad)
{
return(true);
}
return(false);
}
//create on click
private void canvasArea_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
Vec2 currentVel = new Vec2(0, 0);
currentVel = currentVel.Add(creatorVelocity);
var currentRad = creatorRadius;
if (creatorIsBody)
{
Body newBody;
newBody = new Body((int)e.GetPosition(canvasArea).X, (int)e.GetPosition(canvasArea).Y, 0, 0, currentRad);
bodies.Add(newBody);
DrawObjects();
}
else
{
BallV newBall;
newBall = new BallV((int)e.GetPosition(canvasArea).X, (int)e.GetPosition(canvasArea).Y, currentVel, currentRad);
balls.Add(newBall);
DrawObjects();
}
}
