void b2WorldManifold::Initialize()

in Box2D/Collision/b2Collision.cpp [22:83]
54 lines of code
8 McCabe index (conditional complexity)

void b2WorldManifold::Initialize(const b2Manifold* manifold,
						  const b2Transform& xfA, float32 radiusA,
						  const b2Transform& xfB, float32 radiusB)
{
	if (manifold->pointCount == 0)
	{
		return;
	}

	switch (manifold->type)
	{
	case b2Manifold::e_circles:
		{
			normal.Set(1.0f, 0.0f);
			b2Vec2 pointA = b2Mul(xfA, manifold->localPoint);
			b2Vec2 pointB = b2Mul(xfB, manifold->points[0].localPoint);
			if (b2DistanceSquared(pointA, pointB) > b2_epsilon * b2_epsilon)
			{
				normal = pointB - pointA;
				normal.Normalize();
			}

			b2Vec2 cA = pointA + radiusA * normal;
			b2Vec2 cB = pointB - radiusB * normal;
			points[0] = 0.5f * (cA + cB);
		}
		break;

	case b2Manifold::e_faceA:
		{
			normal = b2Mul(xfA.q, manifold->localNormal);
			b2Vec2 planePoint = b2Mul(xfA, manifold->localPoint);
			
			for (int32 i = 0; i < manifold->pointCount; ++i)
			{
				b2Vec2 clipPoint = b2Mul(xfB, manifold->points[i].localPoint);
				b2Vec2 cA = clipPoint + (radiusA - b2Dot(clipPoint - planePoint, normal)) * normal;
				b2Vec2 cB = clipPoint - radiusB * normal;
				points[i] = 0.5f * (cA + cB);
			}
		}
		break;

	case b2Manifold::e_faceB:
		{
			normal = b2Mul(xfB.q, manifold->localNormal);
			b2Vec2 planePoint = b2Mul(xfB, manifold->localPoint);

			for (int32 i = 0; i < manifold->pointCount; ++i)
			{
				b2Vec2 clipPoint = b2Mul(xfA, manifold->points[i].localPoint);
				b2Vec2 cB = clipPoint + (radiusB - b2Dot(clipPoint - planePoint, normal)) * normal;
				b2Vec2 cA = clipPoint - radiusA * normal;
				points[i] = 0.5f * (cA + cB);
			}

			// Ensure normal points from A to B.
			normal = -normal;
		}
		break;
	}
}