OldUnreal (Engine)

Code: Select all

(Global) Var Vector Intersect1, Intersect2;

Function Int FindSphereIntersection(Vector LineStart, Vector LineEnd, Vector SphereOrigin, Float SphereRadius)
{
	//Math, math, math.
	//Math, math, math.
	//Math, math, math.
	
	if (Line from LineStart to LineEnd doesnt intersect with Sphere)
		Return 0;
		
	if (Line from LineStart to LineEnd intersects with Sphere once)
	{
		Intersect1 = Intersect point;
		Return 1;
	}
	
	if (Line from LineStart to LineEnd intersects with Sphere twice)
	{
		Intersect1 = Intersect point;
		Intersect1 = Other intersect point;
		Return 2;
	}
}

Code: Select all

simulated function TraceActor( TDActor A, TR_TraceInfo T )
{
	local float aa,b,c,radii;
	local vector Dir;

	Dir = T.Start - A.Location2D;
	radii = A.CollisionSize.X + T.Extent.X;

	// Simple circle overlap check.
	c = (Dir Dot Dir) - Square(radii);
	if( c<0.f )
	{
		Dir = Normal(Dir);
		if( (Dir Dot T.Dir)<0.1f ) // Only allow to exit from the circle.
			T.SetTraceHit(A,0.f,Dir);
		return;
	}

	aa = T.Dir Dot T.Dir;
	b = 2.f * (Dir Dot T.Dir);

	radii = Square(b) - 4.f*aa*c;
	if( radii < 0 )
	{
		// no intersection
		return;
	}

	// ray didn't totally miss sphere,
	// so there is a solution to
	// the equation.
	// radii = Sqrt( radii );

	// either solution may be on or off the ray so need to test both
	// t1 is always the smaller value, because BOTH discriminant and
	// a are nonnegative.
	c = (-b - Sqrt( radii ))/(2.f*aa);

	if( c >= 0 && c <= 1 )
		T.SetTraceHit(A,c,Normal(T.Start+T.Dir*c-A.Location2D));
}