diff options
Diffstat (limited to 'src/sims/dynamics/joints/SpringJoint.scala')
| -rw-r--r-- | src/sims/dynamics/joints/SpringJoint.scala | 44 |
1 files changed, 22 insertions, 22 deletions
diff --git a/src/sims/dynamics/joints/SpringJoint.scala b/src/sims/dynamics/joints/SpringJoint.scala index 67ea57f..1267ccf 100644 --- a/src/sims/dynamics/joints/SpringJoint.scala +++ b/src/sims/dynamics/joints/SpringJoint.scala @@ -8,13 +8,13 @@ package sims.dynamics.joints import sims.geometry._ -/**Eine Hooksche Feder. - * @param node1 erster Koerper der Verbindung - * @param anchor1 Bindungspunkt auf Koerper eins - * @param node2 zweiter Koerper der Verbindung - * @param anchor2 Bindungspunkt auf Koerper zwei - * @param springConstant Federkonstante - * @param initialLength Initiallaenge +/**A spring obeying Hooke's law. + * @param node1 first associated body + * @param anchor1 first connection point + * @param node2 second associated body + * @param anchor2 second connection point + * @param springConstant spring constant + * @param initialLength initial length */ case class SpringJoint(node1: Body, anchor1: Vector2D, node2: Body, anchor2: Vector2D, springConstant: Double, initialLength: Double) extends Joint with ForceJoint{ @@ -34,25 +34,25 @@ case class SpringJoint(node1: Body, anchor1: Vector2D, node2: Body, anchor2: Vec private val initRotation1 = node1.rotation private val initRotation2 = node2.rotation - /**Ergibt den Bindungspunkt auf Koerper eins.*/ + /**Returns the connection point on body one (in world coordinates).*/ def connection1 = (a1 rotate (node1.rotation - initRotation1)) + node1.pos - /**Ergibt den Bindungspunkt auf Koerper zwei.*/ + /**Returns the connection point on body two (in world coordinates).*/ def connection2 = (a2 rotate (node2.rotation - initRotation2)) + node2.pos - /**Daempfung.*/ + /**Damping.*/ var damping = 0.0 - /**Relative Position der Bindungspunkte.*/ + /**Relative position of the connection points.*/ def x = connection2 - connection1 - /**Relative Geschwindigkeit der Bindungspunkte.*/ + /**Relative velocity of the connection points.*/ def v = node2.velocityOfPoint(connection2) - node1.velocityOfPoint(connection1) - /**Ergibt die Federkraft nach dem Hookschen Gesetz.*/ + /**Returns the spring force.*/ def force = (x.length - initialLength) * springConstant - /**Uebt die Federkraft auf die Bindungspunkte aus.*/ + /**Applies the spring force to the connection points.*/ def applyForce() = { node1.applyForce(x.unit * force - (v * damping) project x, connection1) node2.applyForce(-x.unit * force - (v * damping) project x, connection2) @@ -61,15 +61,15 @@ case class SpringJoint(node1: Body, anchor1: Vector2D, node2: Body, anchor2: Vec def correctVelocity(h: Double) = { /* - val x = this.x //relativer Abstand - val v = this.v //relative Geschwindigkeit - val r1 = (connection1 - node1.pos) //Abstand Punkt-Schwerpunkt, Koerper 1 - val r2 = (connection2 - node2.pos) //Abstand Punkt-Schwerpunkt, Koerper 2 - val cr1 = r1 cross x.unit //Kreuzprodukt - val cr2 = r2 cross x.unit //Kreuzprodukt - val Cdot = x.unit dot v //Velocity-Constraint + val x = this.x + val v = this.v + val r1 = (connection1 - node1.pos) + val r2 = (connection2 - node2.pos) + val cr1 = r1 cross x.unit + val cr2 = r2 cross x.unit + val Cdot = x.unit dot v val invMass = 1/node1.mass + 1/node1.I * cr1 * cr1 + 1/node2.mass + 1/node2.I * cr2 * cr2 //=J M^-1 JT - val m = if (invMass == 0.0) 0.0 else 1/invMass //Test um Nulldivision zu vermeiden + val m = if (invMass == 0.0) 0.0 else 1/invMass val lambda = Math.min(Math.max(-this.force * h, (-m * Cdot)), this.force * h) println (force * h, -m * Cdot) val impulse = x.unit * lambda |