[No bug] AppliedImpulse - Same value for X/Y/Z

[Bananenfreak]

Hello friends,

I found a possible bug. When Worldcollisions are used the values for the applied Impulses received via GetX/Y/Z() are always equal.
Even if there´s only an applied Impulse in one direction (In my code it´s X).

Please try my code and tell my your result. With "Q" you can apply an Impulse on one ball:

Code: Select all

;>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
;>>                             >>
;>>  Name: GetX/Y/Z()-Error     >>
;>>                             >>
;>>  Author: Bananenfreak       >>
;>>                             >>
;>>  Date: 14.02.2016           >>
;>>                             >>
;>>  OS: Windows                >>
;>>                             >>
;>>                             >>
;>>                             >>
;>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
EnableExplicit


Define.f KeyX, KeyY, MouseX, MouseY
Define nx.f, nz.f, Boost.f = 1, Yaw.f, Pitch.f
Define.i Quit
Global.i boden, ball
#kam_0 = 0
#window = 0
#plane = 0
#planent = 0


Procedure BuildUp()
  Protected.i mesh, ent
  
  
  mesh = CreateSphere(#PB_Any, 0.25, 16, 16)
  ball = CreateEntity(#PB_Any, MeshID(mesh), MaterialID(boden), -5, 10.25, 0)
  EntityPhysicBody(ball, #PB_Entity_SphereBody, 5, 0, 0)
  ent = CreateEntity(#PB_Any, MeshID(mesh), MaterialID(boden), 5, 10.25, 0)
  EntityPhysicBody(ent, #PB_Entity_SphereBody, 5, 0, 0)
  mesh = CreateCube(#PB_Any, 1)
  TransformMesh(mesh, 0,0,0, 11, 0.1, 1, 0, 0, 0)
  ent = CreateEntity(#PB_Any, MeshID(mesh), #PB_Material_None, 0, 9.9, 0)
  EntityPhysicBody(ent, #PB_Entity_StaticBody, 5, 0, 0)
  mesh = CreateCube(#PB_Any, 1)
  TransformMesh(mesh, 0,0,0, 11, 1, 0.2, 0, 0, 0)
  ent = CreateEntity(#PB_Any, MeshID(mesh), #PB_Material_None, 0, 10.4, -0.4)
  EntityPhysicBody(ent, #PB_Entity_StaticBody, 5, 0, 0)
  mesh = CreateCube(#PB_Any, 1)
  TransformMesh(mesh, 0,0,0, 11, 1, 0.2, 0, 0, 0)
  ent = CreateEntity(#PB_Any, MeshID(mesh), #PB_Material_None, 0, 10.4, 0.4)
  EntityPhysicBody(ent, #PB_Entity_StaticBody, 5, 0, 0)
  mesh = CreateCube(#PB_Any, 1)
  TransformMesh(mesh, 0,0,0, 0.2, 1, 0.6, 0, 0, 0)
  ent = CreateEntity(#PB_Any, MeshID(mesh), #PB_Material_None, 5.6, 10.4, 0)
  EntityPhysicBody(ent, #PB_Entity_StaticBody, 5, 0, 0)
    mesh = CreateCube(#PB_Any, 1)
  TransformMesh(mesh, 0,0,0, 0.2, 1, 0.6, 0, 0, 0)
  ent = CreateEntity(#PB_Any, MeshID(mesh), #PB_Material_None, -5.6, 10.4, 0)
  EntityPhysicBody(ent, #PB_Entity_StaticBody, 5, 0, 0)
EndProcedure


Procedure PhysikWorker()
  Protected.i first, sec
  
  
  ExamineWorldCollisions(#True)
  
  While NextWorldCollision()
    first = FirstWorldCollisionEntity()
    sec = SecondWorldCollisionEntity()
    
    WorldCollisionAppliedImpulse()
    Debug "X: " + GetX()
    Debug "Y: " + GetY()
    Debug "Z: " + GetZ()
  Wend
EndProcedure


If InitEngine3D()
  
  Add3DArchive(#PB_Compiler_Home + "Examples/3D/Data/Textures", #PB_3DArchive_FileSystem)
  Add3DArchive(#PB_Compiler_Home + "Examples/3D/Data/Scripts", #PB_3DArchive_FileSystem)
  Parse3DScripts()
  
  InitSprite()
  InitKeyboard()
  InitMouse()
  
  OpenWindow(#window, 0, 0, 1800, 1000, "GetX/Y/Z-Bug", #PB_Window_ScreenCentered)
  OpenWindowedScreen(WindowID(#window), 10, 10, 2000, 2000, 1, 10, 10, #PB_Screen_SmartSynchronization)
  
  WorldShadows(#PB_Shadow_TextureAdditive, 200, RGB(255 * 0.2, 255 * 0.2, 255 * 0.2), 4096)
  
  AmbientColor(RGB(255 * 0.2, 255 * 0.2, 255 * 0.2))
  EnableWorldPhysics(#True)
  EnableWorldCollisions(#True)
  
  CreatePlane(#plane, 100, 100, 100, 100, 100, 100)
  boden = GetScriptMaterial(#PB_Any, "Scene/GroundBlend")
  CreateEntity(#planent, MeshID(#plane), MaterialID(boden), 0, 0, 0)
  EntityPhysicBody(#planent, #PB_Entity_StaticBody)
  
  ;-Camera
  CreateCamera(#kam_0, 0, 0, 100, 100)
  MoveCamera(#kam_0, 0, 20, 0, #PB_Absolute)
  CameraLookAt(#kam_0, 20, 0, 20)
  CameraRange (#kam_0, 2, 5000)
  CameraFOV   (#kam_0, 90)
  CameraBackColor(#kam_0, RGB(0, 0, 0))
  
  
  BuildUp()
  
  
  Repeat
    Debug "---------------------------------------"
    Repeat
    Until WindowEvent() = 0
    
    PhysikWorker()
    
    If ExamineMouse()
      Yaw   = -MouseDeltaX() * 0.05
      Pitch = -MouseDeltaY() * 0.05
    EndIf
    
    If ExamineKeyboard()
      
      If KeyboardPushed(#PB_Key_Up)    
        MoveCamera(0,  0, 0, -1 * Boost)
      ElseIf KeyboardPushed(#PB_Key_Down)
        MoveCamera(0,  0, 0,  1 * Boost)
      EndIf 
      
      If KeyboardPushed(#PB_Key_Left)  
        MoveCamera(0, -1 * Boost, 0, 0) 
      ElseIf KeyboardPushed(#PB_Key_Right)
        MoveCamera(0,  1 * Boost, 0, 0)
      EndIf 
      
      If KeyboardReleased(#PB_Key_Q)
        ApplyEntityImpulse(ball, 100, 0, 0)
      EndIf
      
    EndIf
    
    RotateCamera(0, Pitch, Yaw, 0, #PB_Relative)
    
    RenderWorld()
    FlipBuffers()
  Until KeyboardPushed(#PB_Key_Escape) Or Quit = 1
  
Else
  MessageRequester("Error", "The 3D Engine can't be initialized", 0)
EndIf

End

[Comtois]

in previous version WorldCollisionAppliedImpulse() was wrong, it is not a vector, but a float.

Result.f = WorldCollisionAppliedImpulse()

[Bananenfreak]

Uh, sorry
I'm using 5.41 LTS, but haven't looked in the documentation yet.
Haven't used PB for a while (no time for it) and a new Version was released

What about the direction of the applied Impulse? We can get the vector normal to the surface and the Position, but not the direction of the applied Impulse.

And thank you Comtois

[Comtois]

What about the direction of the applied Impulse? We can get the vector normal to the surface and the Position, but not the direction of the applied Impulse.

Indeed, m_appliedImpulse*m_normalWorldOnB is your applied impulse vector.

With PB
m_appliedImpulse = WorldCollisionAppliedImpulse()
m_normalWorldOnB = WorldCollisionNormal()

http://www.bulletphysics.org/Bullet/php ... f=9&t=2568

[Bananenfreak]

Yes Comtois, you're right.
The contact normals are the inversed direction of the applied impulse for the second entity.