public override void AddContacts(RigidBody2D rb, float dt, ref List <Contact2D> contacts)
        {
            //Profiler says this method takes up a lot of processing time (AKA, it's run quite often)
            if (rb as CircleBody != null)
            {
                CircleBody c       = rb as CircleBody;
                Vector2    normal  = rb.Pos - this.Pos;
                float      normLen = normal.Length();
                float      dist    = normLen - (this.radius + c.radius);
                normal /= normLen;
                Vector2 pa = this.Pos + normal * this.radius;
                Vector2 pb = rb.Pos - normal * c.radius;

                contacts.Add(new Contact2D(normal, dist, this, rb, pa, pb));
            }
            else if (rb as LineBody != null)
            {
                LineBody pb = rb as LineBody;
                pb.AddContacts(this, dt, ref contacts);
            }
            else if (rb as CompoundBody != null)
            {
                CompoundBody cb = rb as CompoundBody;
                foreach (CircleBody c in cb.Bodies)
                {
                    this.AddContacts(c, dt, ref contacts);
                }
            }
            else
            {
                throw new NotImplementedException();
            }
        }
        public void AddBody(CircleBody c)
        {
            if (circles.Count <= 0)
            {
                this.Pos        = c.Pos;
                this.InvMass    = c.InvMass;
                this.InvInertia = c.InvInertia;

                c.Pos = Vector2.Zero;

                circles.Add(c);
                return;
            }

            circles.Add(c);

            float currentMass = (InvMass > 0.0f) ? 1f / InvMass : 0.0f;
            float circleMass  = (c.InvMass > 0.0f) ? 1f / c.InvMass : 0f;

            //Calculate new center of mass
            Vector2 newCom = ((currentMass * this.Pos) + (circleMass * c.Pos)) / (currentMass + circleMass);

            //Calculate new inverse mass
            currentMass += circleMass;
            this.InvMass = 1f / currentMass;

            c.Pos = c.Pos - this.Pos;

            float inertia = 0f;

            foreach (CircleBody circle in circles)
            {
                circle.Pos += this.Pos;
                circle.Pos  = circle.Pos - newCom;


                float tempMass = 1f / circle.InvMass;
                //Parallel axis theorem
                inertia += ((tempMass * circle.Radius * circle.Radius)) + tempMass * circle.Pos.LengthSquared();
            }

            this.InvInertia = 1f / inertia;
            this.Pos        = newCom;
        }
        public void AddBody(CircleBody c)
        {
            if (circles.Count <= 0)
            {
                this.Pos = c.Pos;
                this.InvMass = c.InvMass;
                this.InvInertia = c.InvInertia;

                c.Pos = Vector2.Zero;

                circles.Add(c);
                return;
            }

            circles.Add(c);

            float currentMass = (InvMass > 0.0f) ? 1f/InvMass : 0.0f;
            float circleMass = (c.InvMass > 0.0f) ? 1f / c.InvMass : 0f;

            //Calculate new center of mass
            Vector2 newCom = ((currentMass * this.Pos) + (circleMass * c.Pos)) / (currentMass + circleMass);
            //Calculate new inverse mass
            currentMass += circleMass;
            this.InvMass = 1f / currentMass;

            c.Pos = c.Pos - this.Pos;

            float inertia = 0f;

            foreach (CircleBody circle in circles)
            {
                circle.Pos += this.Pos;
                circle.Pos = circle.Pos - newCom;

                float tempMass = 1f / circle.InvMass;
                //Parallel axis theorem
                inertia += ((tempMass*circle.Radius*circle.Radius)) + tempMass * circle.Pos.LengthSquared();
            }

            this.InvInertia = 1f / inertia;
            this.Pos = newCom;
        }
Beispiel #4
0
        public override void AddContacts(RigidBody2D rb, float dt, ref List <Contact2D> contacts)
        {
            if (rb as CircleBody != null)
            {
                CircleBody c    = rb as CircleBody;
                float      dist = DistanceToPoint(c.Pos) - c.Radius;

                Vector2 pointOnPlane = c.Pos - (normal * (dist + c.Radius));
                Vector2 pointOnBall  = c.Pos - (normal * c.Radius);
                contacts.Add(new Contact2D(normal, dist, this, rb, pointOnPlane, pointOnBall));
            }
            else if (rb as LineBody != null)
            {
            }
            else if (rb as CompoundBody != null)
            {
            }
            else
            {
                throw new NotImplementedException();
            }
        }
        public override void AddContacts(RigidBody2D rb, float dt, ref List <Contact2D> contacts)
        {
            //Profiler says this method takes up a lot of processing time (AKA, it's run quite often)
            if (rb as CircleBody != null)
            {
                CircleBody c = rb as CircleBody;

                foreach (CircleBody circle in circles)
                {
                    Vector2 tempPos = circle.Pos;
                    circle.Pos += this.Pos;

                    circle.AddContacts(c, dt, ref contacts);
                    Contact2D justAdded = contacts[contacts.Count - 1];
                    contacts[contacts.Count - 1] = new Contact2D(justAdded.Normal, justAdded.Dist, this, justAdded.B, justAdded.pointA, justAdded.pointB);

                    circle.Pos = tempPos;
                }
            }
            else if (rb as LineBody != null)
            {
                foreach (CircleBody circle in circles)
                {
                    Vector2 tempPos = circle.Pos;
                    circle.Pos += this.Pos;

                    circle.AddContacts(rb, dt, ref contacts);
                    Contact2D justAdded = contacts[contacts.Count - 1];
                    contacts[contacts.Count - 1] = new Contact2D(justAdded.Normal, justAdded.Dist, justAdded.A, this, justAdded.pointA, justAdded.pointB);

                    circle.Pos = tempPos;
                }
            }
            else
            {
                throw new NotImplementedException();
            }
        }
 public void RemoveBody(CircleBody c)
 {
     circles.Remove(c);
 }
 public void RemoveBody(CircleBody c)
 {
     circles.Remove(c);
 }
Beispiel #8
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        public override void Update(GameTime g)
        {
            base.Update(g);

            cam.Update(g);

            if (InputHandler.MouseState.LeftButton == ButtonState.Pressed && InputHandler.LastMouseState.LeftButton == ButtonState.Released)
            {
                mouseHeldDown = true;
                mouseForceStart = cam.GetWorldMousePos();
            }
            else if (InputHandler.MouseState.LeftButton != ButtonState.Pressed)
            {
                mouseHeldDown = false;
            }

            if (InputHandler.MouseState.RightButton == ButtonState.Pressed)
            {
                float radius = rand.Next(10, 50) / 100f;
                //RigidBody2D rb = new CircleBody(cam.GetWorldMousePos(), new Vector2(0, 0), 0.0f, MathHelper.Pi * radius*radius * 100, radius);
                RigidBody2D rb = new CircleBody(cam.GetWorldMousePos(), Vector2.Zero, 0f, 2f, 0.2f);
                engine.AddRigidBody(rb);
            }

            Vector2 force = Vector2.Zero;
            Vector2 mouseWorldPos = cam.GetWorldMousePos();
            if (mouseHeldDown)
            {
                force = mouseWorldPos - mouseForceStart;
                foreach (RigidBody2D rb in engine.GetBodies())
                {
                    rb.AddForce(force);
                }
            }

            if (!InputHandler.IsKeyPressed(Keys.Space))
            {
                engine.Update(g);
            }
            else if (InputHandler.IsNewKeyPress(Keys.Right))
            {
                engine.Update(g);
            }
        }
Beispiel #9
0
        private void setupEngine()
        {
            engine = new PhysicsEngine2D();
            int bodyCount = 1;
            for (int i = 0; i < bodyCount; i++)
            {
                engine.AddRigidBody(new CircleBody(new Vector2(i+2, 8), new Vector2(0, 0), 0f, 0f, 0.2f));
            }

            for (int i = 0; i < bodyCount; i++)
            {
                RigidBody2D rb = new CircleBody(new Vector2(i +2, 6), new Vector2(1 , 0), 0.0f, 10f, 0.2f);
                engine.AddRigidBody(rb);
                engine.AddConstraint(new DistanceConstraint2D(rb, engine.GetBodies()[0], 4));
            }

            engine.AddRigidBody(new LineBody(Vector2.UnitY, Vector2.Zero));
            engine.AddRigidBody(new LineBody(Vector2.UnitX, Vector2.Zero));
            engine.AddRigidBody(new LineBody(-Vector2.UnitY, new Vector2(0, 10)));
            engine.AddRigidBody(new LineBody(-Vector2.UnitX, new Vector2(20, 0)));
        }