FarseerPhysics Work Item Rss Feed

Created Issue: Arbiter.cs line 180 Error [25159]

simonzb — Fri, 30 Oct 2009 10:11:26 GMT

In arbiter.cs line 180 : _normalImpulse = _contact.massNormal * -(_vn + _contact.bounceVelocity);

I found that the _vn is in same direction with _contact.bounceVelocity, which makes the bouncing speed double.

I found that _normalImpulse = _contact.massNormal * (-_vn + _contact.bounceVelocity); works well when I play with balls.

Created Issue: Velocity direction after Collision is not correct. [25157]

simonzb — Fri, 30 Oct 2009 03:33:30 GMT

I have one ball in the borders. When the ball hit the wall, the ball should go to the reflect direction according to it's collision normal. But 2.1.2 engine make the direct in a incorrect way.

Created Issue: Math Exception on Demo 6 [25137]

ddreier — Thu, 29 Oct 2009 05:49:13 GMT

In demo 6 an exception is thrown when trying to click on the "chain" attached to the agent while it is in the lower left section of the 'level.' I was able to replicate it, and have the exception detail for each time.

First Time:
System.ArithmeticException was unhandled
Message="Function does not accept floating point Not-a-Number values."
Source="mscorlib"
StackTrace:
at System.Math.Sign(Single value)
at FarseerGames.FarseerPhysics.Dynamics.Springs.FixedAngleSpring.Update(Single dt) in G:\Farseer Physics 2.1.2 XNA with simple samples\Farseer Physics 2.1.2 XNA\Dynamics\Springs\FixedAngleSpring.cs:line 95
at FarseerGames.FarseerPhysics.PhysicsSimulator.ApplyForces(Single dt, Single dtReal) in G:\Farseer Physics 2.1.2 XNA with simple samples\Farseer Physics 2.1.2 XNA\PhysicsSimulator.cs:line 540
at FarseerGames.FarseerPhysics.PhysicsSimulator.Update(Single dt, Single dtReal) in G:\Farseer Physics 2.1.2 XNA with simple samples\Farseer Physics 2.1.2 XNA\PhysicsSimulator.cs:line 403
at FarseerGames.FarseerPhysics.PhysicsSimulator.Update(Single dt) in G:\Farseer Physics 2.1.2 XNA with simple samples\Farseer Physics 2.1.2 XNA\PhysicsSimulator.cs:line 352
at DemoBaseXNA.ScreenSystem.GameScreen.Update(GameTime gameTime, Boolean otherScreenHasFocus, Boolean coveredByOtherScreen) in G:\Farseer Physics 2.1.2 XNA with simple samples\DemoBaseXNA\ScreenSystem\GameScreen.cs:line 211
at DemoBaseXNA.ScreenSystem.ScreenManager.Update(GameTime gameTime) in G:\Farseer Physics 2.1.2 XNA with simple samples\DemoBaseXNA\ScreenSystem\ScreenManager.cs:line 198
at Microsoft.Xna.Framework.Game.Update(GameTime gameTime)
at Microsoft.Xna.Framework.Game.Tick()
at Microsoft.Xna.Framework.Game.HostIdle(Object sender, EventArgs e)
at Microsoft.Xna.Framework.GameHost.OnIdle()
at Microsoft.Xna.Framework.WindowsGameHost.ApplicationIdle(Object sender, EventArgs e)
at System.Windows.Forms.Application.ThreadContext.System.Windows.Forms.UnsafeNativeMethods.IMsoComponent.FDoIdle(Int32 grfidlef)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.Run(Form mainForm)
at Microsoft.Xna.Framework.WindowsGameHost.Run()
at Microsoft.Xna.Framework.Game.Run()
at FarseerGames.SimpleSamplesXNA.Program.Main() in G:\Farseer Physics 2.1.2 XNA with simple samples\SimpleSamplesXNA\Program.cs:line 12
InnerException:

Second Time:
System.ArithmeticException was unhandled
Message="Function does not accept floating point Not-a-Number values."
Source="mscorlib"
StackTrace:
at System.Math.Sign(Single value)
at FarseerGames.FarseerPhysics.Dynamics.Springs.FixedAngleSpring.Update(Single dt) in G:\Farseer Physics 2.1.2 XNA with simple samples\Farseer Physics 2.1.2 XNA\Dynamics\Springs\FixedAngleSpring.cs:line 95
at FarseerGames.FarseerPhysics.PhysicsSimulator.ApplyForces(Single dt, Single dtReal) in G:\Farseer Physics 2.1.2 XNA with simple samples\Farseer Physics 2.1.2 XNA\PhysicsSimulator.cs:line 540
at FarseerGames.FarseerPhysics.PhysicsSimulator.Update(Single dt, Single dtReal) in G:\Farseer Physics 2.1.2 XNA with simple samples\Farseer Physics 2.1.2 XNA\PhysicsSimulator.cs:line 403
at FarseerGames.FarseerPhysics.PhysicsSimulator.Update(Single dt) in G:\Farseer Physics 2.1.2 XNA with simple samples\Farseer Physics 2.1.2 XNA\PhysicsSimulator.cs:line 352
at DemoBaseXNA.ScreenSystem.GameScreen.Update(GameTime gameTime, Boolean otherScreenHasFocus, Boolean coveredByOtherScreen) in G:\Farseer Physics 2.1.2 XNA with simple samples\DemoBaseXNA\ScreenSystem\GameScreen.cs:line 211
at DemoBaseXNA.ScreenSystem.ScreenManager.Update(GameTime gameTime) in G:\Farseer Physics 2.1.2 XNA with simple samples\DemoBaseXNA\ScreenSystem\ScreenManager.cs:line 198
at Microsoft.Xna.Framework.Game.Update(GameTime gameTime)
at Microsoft.Xna.Framework.Game.Tick()
at Microsoft.Xna.Framework.Game.HostIdle(Object sender, EventArgs e)
at Microsoft.Xna.Framework.GameHost.OnIdle()
at Microsoft.Xna.Framework.WindowsGameHost.ApplicationIdle(Object sender, EventArgs e)
at System.Windows.Forms.Application.ThreadContext.System.Windows.Forms.UnsafeNativeMethods.IMsoComponent.FDoIdle(Int32 grfidlef)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.Run(Form mainForm)
at Microsoft.Xna.Framework.WindowsGameHost.Run()
at Microsoft.Xna.Framework.Game.Run()
at FarseerGames.SimpleSamplesXNA.Program.Main() in G:\Farseer Physics 2.1.2 XNA with simple samples\SimpleSamplesXNA\Program.cs:line 12
InnerException:

Commented Issue: Texture To Vertices Bug [23136]

sickbattery — Wed, 14 Oct 2009 08:03:07 GMT

When you create circular textures (or ones with rounded edges for that matter) via TTV a vertex is missing. See this for details.
Comments: ** Comment from web user: sickbattery **

I don't know if the mod of the second function is that important. Maybe that's why I forgot about it at first. Sorry!
(I would apply it anyway. Just to make sure ... It's a bit faster and more stable.)

Commented Issue: Texture To Vertices Bug [23136]

sickbattery — Wed, 14 Oct 2009 07:56:45 GMT

When you create circular textures (or ones with rounded edges for that matter) via TTV a vertex is missing. See this for details.
Comments: ** Comment from web user: sickbattery **

Fixed. See attachment.

Commented Issue: Texture To Vertices Bug [23136]

genbox — Fri, 09 Oct 2009 12:19:58 GMT

When you create circular textures (or ones with rounded edges for that matter) via TTV a vertex is missing. See this for details.
Comments: ** Comment from web user: genbox **

Original post here: http://farseerphysics.codeplex.com/Thread/View.aspx?ThreadId=59901

Closed Issue: Farseer and VB.NET [24126]

genbox — Thu, 08 Oct 2009 17:23:32 GMT

Text removed ...

If I compile the defaul Class Library VB.NET can't find the implementation of body.ApplyForce since it's not "unique" ( i am using german VB, the error message is: "ApplyForce" ist mehrdeutig, da in class "FarseerGames.FarseerPhysics.Dynamics.Body" mehrere Arten von Membern mit diesem Namen vorhanden sind. ). So I fixed that issue by renaming the methods (to ApplyForce and ApplyForceRef).
Comments:

Closed Issue: more different collision events [22363]

genbox — Thu, 08 Oct 2009 17:21:14 GMT

the following issues:
http://farseerphysics.codeplex.com/Thread/View.aspx?ThreadId=56165
http://farseerphysics.codeplex.com/Thread/View.aspx?ThreadId=56162

could they be implemented directly in the engine more easily somehow?
Comments:

New contact system is being developed. This issue will have to be reevaluated in the future.

Closed Issue: Silverlight: Exception with slight modification to sample. [21378]

genbox — Thu, 08 Oct 2009 17:19:38 GMT

If I alter GameModel.cs inside the water sample for SilverLight, changing the size of the boxes in the pyramid:

InitializePyrmid(new Vector2(308, 170), 20, 20, 2, 2, 5);

to

InitializePyrmid(new Vector2(308, 170), 5, 5, 2, 2, 5);

Then after 3 seconds (after the initial collisions of the little boxes + box with water), I get the following exception:

System.ArgumentException was unhandled by user code
Message="Value does not fall within the expected range."
StackTrace:
at MS.Internal.XcpImports.CheckHResult(UInt32 hr)
at MS.Internal.XcpImports.SetValue(INativeCoreTypeWrapper obj, DependencyProperty property, Double d)
at System.Windows.DependencyObject.SetValue(DependencyProperty property, Double d)
at System.Windows.Media.RotateTransform.set_Angle(Double value)
at FarseerGames.WaterSample.RenderSystem.Sprite.set_Rotation(Double value)
at FarseerGames.WaterSample.Views.BoxView.Draw()
at FarseerGames.WaterSample.Views.GameView.Draw(TimeSpan elapsedTime)
at FarseerGames.WaterSample.RenderSystem.RenderLoop.StepEventHandler.Invoke(TimeSpan elapsedTime)
at FarseerGames.WaterSample.RenderSystem.RenderLoop.Render()
at FarseerGames.WaterSample.RenderSystem.RenderLoop.CompositionTarget_Rendering(Object sender, EventArgs e)
at System.Windows.Media.CompositionTarget.OnRendering(Object sender, RenderingEventArgs e)
at MS.Internal.JoltHelper.RaiseEvent(IntPtr target, UInt32 eventId, IntPtr coreEventArgs, UInt32 eventArgsTypeIndex)
InnerException:

The error occurs on the setter of:

public double Rotation
{
get { return RotateTransform.Angle; }
set { RotateTransform.Angle = value; }
}

> WaterSample!FarseerGames.WaterSample.RenderSystem.Sprite.Rotation.set(double value = Infinity) Line 24 + 0x1f bytes C#

watching the value, it shows as NaN

- this {FarseerGames.WaterSample.Views.BoxView} FarseerGames.WaterSample.Views.BoxView
+ _sprite {FarseerGames.WaterSample.RenderSystem.Sprite} FarseerGames.WaterSample.RenderSystem.Sprite
- BoxModel {FarseerGames.WaterSample.Models.BoxModel} FarseerGames.WaterSample.Models.BoxModel
_def null FarseerGames.WaterSample.Models.BoxModelDef
- Body {FarseerGames.FarseerPhysics.Dynamics.Body} FarseerGames.FarseerPhysics.Dynamics.Body
+ _acceleration {X:-0.5476902 Y:4.471687} FarseerGames.FarseerPhysics.Mathematics.Vector2
_bodyAngularVelocity Infinity float
+ _bodylinearVelocity {X:10.94833 Y:-9.389012} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ _bodyMatrixTemp {FarseerGames.FarseerPhysics.Mathematics.Matrix} FarseerGames.FarseerPhysics.Mathematics.Matrix
+ _diff {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ _dp {X:0.1094832 Y:-0.09389012} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ _dv {X:-0.005476902 Y:0.04471687} FarseerGames.FarseerPhysics.Mathematics.Vector2
_dw Infinity float
+ _linearDrag {X:-0.0109538 Y:0.00943373} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ _localPositionTemp {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
_momentOfInertia 0.0000333333264 float
_previousAngularVelocity -4.53407176E+20 float
+ _previousLinearVelocity {X:10.9538 Y:-9.433729} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ _previousPosition {X:7.007465 Y:5.327279} FarseerGames.FarseerPhysics.Mathematics.Vector2
_previousRotation -4.53407177E+18 float
+ _quadraticDrag {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ _r1 {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
_revolutions 61872775 int
_rotationalDrag Infinity float
_rotationChange Infinity float
+ _rotationMatrixTemp {FarseerGames.FarseerPhysics.Mathematics.Matrix} FarseerGames.FarseerPhysics.Mathematics.Matrix
_speed 0.0 float
+ _tempVelocity {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
_torque 0.0 float
+ _totalDrag {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ _translationMatrixTemp {FarseerGames.FarseerPhysics.Mathematics.Matrix} FarseerGames.FarseerPhysics.Mathematics.Matrix
+ _worldPositionTemp {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
AngularVelocity Infinity float
angularVelocityBias 0.0 float
+ Disposed {System.EventHandler<System.EventArgs>} System.EventHandler<System.EventArgs>
Enabled true bool
+ force {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ Force {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
IdleTime 0.0 float
IgnoreGravity false bool
+ impulse {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
InverseMass 50.0000076 float
inverseMass 50.0000076 float
InverseMomentOfInertia 30000.0059 float
inverseMomentOfInertia 30000.0059 float
IsAutoIdle false bool
IsDisposed false bool
IsQuadraticDragEnabled false bool
IsStatic false bool
isStatic false bool
LinearDragCoefficient 0.001 float
+ LinearVelocity {X:10.94833 Y:-9.389012} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ linearVelocityBias {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
mass 0.0199999977 float
Mass 0.0199999977 float
MinimumVelocity 55.0 float
MomentOfInertia 0.0000333333264 float
Moves false bool
+ position {X:7.116949 Y:5.233388} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ Position {X:7.116949 Y:5.233388} FarseerGames.FarseerPhysics.Mathematics.Vector2
QuadraticDragCoefficient 0.001 float
Revolutions 61872775 int
rotation Infinity float
Rotation Infinity float
RotationalDragCoefficient 0.001 float
Tag null object
Torque 0.0 float
totalRotation Infinity float
TotalRotation Infinity float
+ Updated {FarseerGames.FarseerPhysics.Dynamics.Body.UpdatedEventHandler} FarseerGames.FarseerPhysics.Dynamics.Body.UpdatedEventHandler
+ XVectorInWorldCoordinates {X:NaN Y:NaN} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ YVectorInWorldCoordinates {X:NaN Y:NaN} FarseerGames.FarseerPhysics.Mathematics.Vector2
- Geom {FarseerGames.FarseerPhysics.Collisions.Geom} FarseerGames.FarseerPhysics.Collisions.Geom
_collisionGridCellSize 0.01 float
_isSensor false bool
+ _localVertice {X:-0.025 Y:-0.05} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ _matrix {FarseerGames.FarseerPhysics.Mathematics.Matrix} FarseerGames.FarseerPhysics.Mathematics.Matrix
+ _matrixInverse {FarseerGames.FarseerPhysics.Mathematics.Matrix} FarseerGames.FarseerPhysics.Mathematics.Matrix
+ _matrixInverseTemp {FarseerGames.FarseerPhysics.Mathematics.Matrix} FarseerGames.FarseerPhysics.Mathematics.Matrix
+ _newPos {X:NaN Y:NaN} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ _offset {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ _position {X:NaN Y:NaN} FarseerGames.FarseerPhysics.Mathematics.Vector2
_rotation Infinity float
_rotationOffset 0.0 float
+ _vector {X:0 Y:0} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ _vertice {X:NaN Y:NaN} FarseerGames.FarseerPhysics.Mathematics.Vector2
+ aabb {FarseerGames.FarseerPhysics.Collisions.AABB} FarseerGames.FarseerPhysics.Collisions.AABB
+ AABB {FarseerGames.FarseerPhysics.Collisions.AABB} FarseerGames.FarseerPhysics.Collisions.AABB
+ body {FarseerGames.FarseerPhysics.Dynamics.Body} FarseerGames.FarseerPhysics.Dynamics.Body
+ Body {FarseerGames.FarseerPhysics.Dynamics.Body} FarseerGames.FarseerPhysics.Dynamics.Body
CollidesWith All FarseerGames.FarseerPhysics.CollisionCategory
collidesWith All FarseerGames.FarseerPhysics.CollisionCategory
CollisionCategories All FarseerGames.FarseerPhysics.CollisionCategory
collisionCategories All FarseerGames.FarseerPhysics.CollisionCategory
collisionEnabled true bool
CollisionEnabled true bool
CollisionGridCellSize 0.01 float
CollisionGroup 0 int
collisionGroup 0 int
collisionResponseEnabled true bool
CollisionResponseEnabled true bool
FrictionCoefficient 0.2 float
frictionCoefficient 0.2 float
+ Grid {FarseerGames.FarseerPhysics.Collisions.Grid} FarseerGames.FarseerPhysics.Collisions.Grid
+ grid {FarseerGames.FarseerPhysics.Collisions.Grid} FarseerGames.FarseerPhysics.Collisions.Grid
Id 12 int
IsDisposed false bool
isRemoved false bool
IsSensor false bool
+ localVertices Count = 16 FarseerGames.FarseerPhysics.Collisions.Vertices
+ LocalVertices Count = 16 FarseerGames.FarseerPhysics.Collisions.Vertices
+ Matrix {FarseerGames.FarseerPhysics.Mathematics.Matrix} FarseerGames.FarseerPhysics.Mathematics.Matrix
+ MatrixInverse {FarseerGames.FarseerPhysics.Mathematics.Matrix} FarseerGames.FarseerPhysics.Mathematics.Matrix
OnCollision null FarseerGames.FarseerPhysics.Collisions.Geom.CollisionEventHandler
OnSeparation null FarseerGames.FarseerPhysics.Collisions.Geom.SeparationEventHandler
+ Position {X:NaN Y:NaN} FarseerGames.FarseerPhysics.Mathematics.Vector2
restitutionCoefficient 0.0 float
RestitutionCoefficient 0.0 float
Rotation Infinity float
Tag null object
+ WorldVertices Count = 16 FarseerGames.FarseerPhysics.Collisions.Vertices
+ worldVertices Count = 16 FarseerGames.FarseerPhysics.Collisions.Vertices
+ Static members
Height 0.099999994 float
Mass 0.0199999977 float
Width 0.099999994 float

Just playing around, so obviously no urgency - I took a look to see if I could find anything but couldn't get my head around it.
Comments:

When the values are too large or too small, it cause numerical explosions to happen. (overflow). Some small checks have been made to sanitize the values.

Closed Issue: Garbage Issues (Proposed Fixes) [23534]

genbox — Thu, 08 Oct 2009 17:17:21 GMT

Hello,

I've found some garbage issues with Farseer Physics 2.1.1 and fixed them; the main one is in Vertices.cs, in the GetCentroid function. The GetCentroid function should be:

public Vector2 GetCentroid(float area) { //calc centroid on counter clockwise verts. -- this generates lots of garbage... //Vertices verts = new Vertices(this); //verts.ForceCounterClockWiseOrder(); Vertices verts = this; float cx = 0, cy = 0; int i; float signedarea = GetSignedArea(); float factor; if(signedarea > 0) //if it's meant to be reversed, go through the vertices backwards { for (i = Count - 1; i >= 0; i--) { int j = (i - 1) % Count; if(j < 0) { j += Count; } factor = -(verts[i].X * verts[j].Y - verts[j].X * verts[i].Y); cx += (verts[i].X + verts[j].X) * factor; cy += (verts[i].Y + verts[j].Y) * factor; } } else { for (i = 0; i < Count; i++) { int j = (i + 1) % Count; factor = -(verts[i].X * verts[j].Y - verts[j].X * verts[i].Y); cx += (verts[i].X + verts[j].X) * factor; cy += (verts[i].Y + verts[j].Y) * factor; } } area *= 6.0f; factor = 1 / area; cx *= factor; cy *= factor; _res.X = cx; _res.Y = cy; return _res; }

This will make it generate no garbage. Also, Arbiters generate a bit of garbage too; Fixing these is a bit more complex. The problem is that they allocate new contact lists in their construct method: to get around this, the contact lists should be allocated when the Pool<Arbiter> is allocated beforehand, otherwise every created arbiter generates a bit of garbage rather than using a prechaced contact list. This also means the Pool needs to be made enumerable so you can call your InitContactLists function for each Arbiter in the pool before they are constructed - there was an older topic about this that explained it with a code sample but it must've not been integrated into Farseer.

Another source of garbage is the default list allocations: most of the lists are created without supplying a capacity value. There's very little memory footprint (we're talking a couple of hundred bytes per list) in specifying a default allocation of about 64 for every list, and this prevents garbage being generated each time the list goes over its capacity. This is also true for the ArbiterList and GenericList classes, which should implement a constructor where you can supply a default capacity (since they inherit from List<T> this is easy: just do base.Capacity = capacity in a constructor accepting an int capacity parameter).

EDIT: Also, the AABB class would make more sense as a struct - especially in the case of the sweep and prunce collider, which has some garbage generated from allocating AABBs for intersection tests.
Comments:

Fixed in 2.1.2

Closed Issue: Body.ResetDynamics issue [24175]

genbox — Thu, 08 Oct 2009 17:06:38 GMT

Hello!

I have bullets and targets, when a bullet hit something i disable its body and call ResetDynamics. This reset all the properties of Body, but the Geom properties remain untouched, Geom.Position and Geom.Rotation hold the position and rotation of the collision, while Body.Position = 0,0 and Body.Rotation = 0
To fix that i think you only need to add this piece of code:
if (Updated != null)
{
Updated(ref position, ref rotation);
}

at the end of Body.ResetDynamics.

Thanks
Comments:

Fixed in Farseer Physics Engine 2.1.2

Closed Issue: Geom.RestitutionCoefficient = 0 Issue [24351]

genbox — Thu, 08 Oct 2009 17:02:54 GMT

I'm writing a splosion-man-like game where I want the player stick to the walls when he hits them (and then jump away if jump pressed). I set all of the objects RestitutionCoefficient to zero but when player hits a wall it bounces back a little.
My workaround is to set the X component of LinearVelocity to zero when player collides with another object (Using OnCollision event).
I have experience writing a physics engine myself and I know this shouldn't happen.
Comments:

The restitution of two geometries are averaged on impact. You need to set the restitution of both the geometries to 0 to achieve no restitution (bounce).

Created Issue: Geom.RestitutionCoefficient = 0 Issue

KamiSama — Sun, 16 Aug 2009 22:44:33 GMT

Closed Issue: Unable to download

genbox — Wed, 05 Aug 2009 20:59:13 GMT

Unable to download any items from the download links. Please fix the download links.
Comments:

Codeplex must have had some issues. The links under the Downloads tab works fine here.

Created Issue: Unable to download

rrv — Wed, 05 Aug 2009 03:54:32 GMT

Unable to download any items from the download links. Please fix the download links.

Created Issue: Body.ResetDynamics issue

genbox — Fri, 31 Jul 2009 02:01:32 GMT

Commented Issue: Farseer and VB.NET

fixitchris — Tue, 28 Jul 2009 15:56:27 GMT

I would not use VB to do XNA work. There have been articles posted on the limitations.

Created Issue: Farseer and VB.NET

genbox — Tue, 28 Jul 2009 06:48:41 GMT

Commented Issue: Garbage Issues (Proposed Fixes)

genbox — Fri, 17 Jul 2009 21:12:44 GMT

Original discussion is here: http://farseerphysics.codeplex.com/Thread/View.aspx?ThreadId=61765

Created Issue: Garbage Issues (Proposed Fixes)

genbox — Fri, 17 Jul 2009 21:12:04 GMT