ApplyForce() public method

Apply a force at a world point. If the force is not applied at the center of mass, it will generate a torque and affect the angular velocity. This wakes up the body.
public ApplyForce ( System.Vector2 force, System.Vector2 point ) : void
force System.Vector2 The world force vector, usually in Newtons (N).
point System.Vector2 The world position of the point of application.
return void
Body Class Documentation
Example #1
0
		/// <summary>
		/// Add a spring force
		/// </summary>
		void AddSpringForce(Body bA, Vec2 localA, Body bB, Vec2 localB, float k, float friction, float desiredDist)
		{
			Vec2 pA = bA.GetWorldPoint(localA);
			Vec2 pB = bB.GetWorldPoint(localB);
			Vec2 diff = pB - pA;
			//Find velocities of attach points
			Vec2 vA = bA.GetLinearVelocity() - Vec2.Cross(bA.GetWorldVector(localA), bA.GetAngularVelocity());
			Vec2 vB = bB.GetLinearVelocity() - Vec2.Cross(bB.GetWorldVector(localB), bB.GetAngularVelocity());
			Vec2 vdiff = vB - vA;
			float dx = diff.Normalize(); //normalizes diff and puts length into dx
			float vrel = vdiff.X * diff.X + vdiff.Y * diff.Y;
			float forceMag = -k * (dx - desiredDist) - friction * vrel;
			diff *= forceMag; // diff *= forceMag
			bB.ApplyForce(diff, bA.GetWorldPoint(localA));
			diff *= -1.0f;
			bA.ApplyForce(diff, bB.GetWorldPoint(localB));
		}
Example #2
0
        void killWheelOrthogonalVelocity(Body hull, Body wheel)
        {
            var p_hull = hull.GetPosition();
            var p_wheel = wheel.GetPosition();
            var velocity = wheel.GetLinearVelocityFromLocalPoint(Vec2.Zero);

            var vec1 = wheel.GetXForm().R.Col1;
            var projection = Vec2.Dot(velocity, vec1);
            vec1 *= projection;

            var k = vec1.Length() / 0.001f; // превышение боковой скорости 1 мм / с
            if (k < 0.1f) k = 0.1f; if (k > 10f) k = 10f;
            float force = -k * 3000; //warning - mn

            vec1.Normalize();

            hull.ApplyForce(force * vec1, p_wheel);
        }