PureBasic Forums - English

Posted: **Mon Aug 26, 2024 8:02 am**

Function 'VertexBoneAssignment()' it seems that it does not attend to its 'Weight.f' parameter for the bone index 0:
as i understand, when this parameter is near to 0.0 there should result in almost no modification of those vertexes white rotating or moving the bone, but the effect is the same than a max value, i.e. 'Weight'=1.0
Test:

Code: Select all

InitEngine3D(#PB_Engine3D_NoLog,#PB_Compiler_Home+"Compilers\Engine3d.dll"):InitSprite():InitKeyboard():InitMouse()
OpenWindow(0, 0,0, 1280,720, "[Esc] to end",#PB_Window_ScreenCentered)
OpenWindowedScreen(WindowID(0), 0, 0, WindowWidth(0), WindowHeight(0), 0, 0, 0)
CreateCamera(0, 0, 0, 100, 100):MoveCamera(0,0,1,4):CameraLookAt(0,0,0,0):CameraBackColor(0,$446666)
CreateLight(0,$ffffff, 10, 10, 0)
CreateShaderMaterial(0,#PB_Material_ColorShader)
SetMaterialColor(0,#PB_Material_AmbientColor|#PB_Material_DiffuseColor,$4455ff):MaterialShininess(0,64,$ffffff)
MaterialCullingMode(0,#PB_Material_NoCulling)
;creacion del esqueleto
CreateCylinder(0,0.2,1,6,4,0):TransformMesh(0,0,1/2,0,1,1,1,0,0,0,0)
CreateSkeleton(0)
;juntas del esqueleto:
CreateSphere(10,0.05)
CreateMaterial(10,0,$eeeeee)
junta$="junta"
CreateBone(0,junta$,"",0,0,0,0,0,0,0,#PB_Orientation_PitchYawRoll)
CreateEntity(10,MeshID(10),MaterialID(10))
for i.a=0 to 13
  VertexBoneAssignment(0,0,i,0,0.001); <- This command does not listen to its 'Weight.f' parameter:
  ;to assign bone index 0 an influence of 0.001 to first 14 vertexes of the mesh
  ;should result in almost no modification of those vertexes white rotating the bone,
  ;but the effect is the same than a max value, i.e. 'Weight'=1.0
Next
FinishBoneAssignment(0,0)
CreateEntity(0,MeshID(0),MaterialID(0))
MaterialShadingMode(0,#PB_Material_Wireframe)
Repeat:While WindowEvent():Wend
  ExamineKeyboard():ExamineMouse()
  MouseX.f=MouseDeltaX()*5E-2:MouseY.f=MouseDeltaY()*5E-2
  RotateCamera(0,MouseY.f,MouseX.f,0,#PB_Relative)
  MoveCamera(0,0,0,MouseWheel())
  EnableManualEntityBoneControl(0,junta$,1,1)
  RotateEntityBone(0,junta$,0,0,1,#PB_Relative)
  RenderWorld()
  FlipBuffers():Delay(11)
Until KeyboardPushed(#PB_Key_Escape)

Posted: **Tue Aug 27, 2024 5:09 am**

Not confirmed. There is only one bone affecting the vertices, the weight is considered as 1 (full control). The first bone is considered as root bone ( bone that has no parent ). Usually we do not assign any vertices to it, use it as a base of your skeleton, and use the child bones for that matter.

Here's the code I used for test:

Code: Select all

InitEngine3D(#PB_Engine3D_NoLog,#PB_Compiler_Home+"Compilers\Engine3d.dll"):InitSprite():InitKeyboard():InitMouse()
OpenWindow(0, 0,0, 1280,720, "[Esc] to end",#PB_Window_ScreenCentered)
OpenWindowedScreen(WindowID(0), 0, 0, WindowWidth(0), WindowHeight(0), 0, 0, 0)
CreateCamera(0, 0, 0, 100, 100):MoveCamera(0,0,1,4):CameraLookAt(0,0,0,0):CameraBackColor(0,$446666)
CreateLight(0,$ffffff, 10, 10, 0)
CreateShaderMaterial(0,#PB_Material_ColorShader)
SetMaterialColor(0,#PB_Material_AmbientColor|#PB_Material_DiffuseColor,$4455ff):MaterialShininess(0,64,$ffffff)
MaterialCullingMode(0,#PB_Material_NoCulling)
;creacion del esqueleto
CreateCylinder(0,0.2,1,6,4,0):TransformMesh(0,0,1/2,0,1,1,1,0,0,0,0)
CreateSkeleton(0)
;juntas del esqueleto:
CreateSphere(10,0.05)
CreateMaterial(10,0,$eeeeee)
junta$="junta"
junta2$="junta2"
CreateBone(0,junta$,"",0,0,0,0,0,0,0,#PB_Orientation_PitchYawRoll)
CreateBone(0,junta2$,junta$,0,1,0,0,0,0,0,#PB_Orientation_PitchYawRoll)
CreateEntity(10,MeshID(10),MaterialID(10))
For i.a=0 To 26
  VertexBoneAssignment(0,0,i,0,0.9); <- This command does not listen to its 'Weight.f' parameter:
  VertexBoneAssignment(0,0,i,1,0.1); <- This command does not listen to its 'Weight.f' parameter:

  ;to assign bone index 0 an influence of 0.001 to first 14 vertexes of the mesh
  ;should result in almost no modification of those vertexes white rotating the bone,
  ;but the effect is the same than a max value, i.e. 'Weight'=1.0
Next
FinishBoneAssignment(0,0)
CreateEntity(0,MeshID(0),MaterialID(0))
MaterialShadingMode(0,#PB_Material_Wireframe)
Repeat:While WindowEvent():Wend
  ExamineKeyboard():ExamineMouse()
  MouseX.f=MouseDeltaX()*5E-2:MouseY.f=MouseDeltaY()*5E-2
  RotateCamera(0,MouseY.f,MouseX.f,0,#PB_Relative)
  MoveCamera(0,0,0,MouseWheel())
  EnableManualEntityBoneControl(0,junta$,1,1)
  EnableManualEntityBoneControl(0,junta2$,1,1)
  RotateEntityBone(0,junta$,0,0,1,#PB_Relative)
  RotateEntityBone(0,junta2$,1,1,0,#PB_Relative)
  RenderWorld()
  FlipBuffers():Delay(11)
Until KeyboardPushed(#PB_Key_Escape)

Posted: **Tue Aug 27, 2024 10:18 am**

seems a bug to me

Posted: **Tue Aug 27, 2024 12:24 pm**

miso wrote: Tue Aug 27, 2024 5:09 am Not confirmed. There is only one bone affecting the vertices, the weight is considered as 1 (full control). The first bone is considered as root bone ( bone that has no parent ). Usually we do not assign any vertices to it, use it as a base of your skeleton, and use the child bones for that matter.

I know there are engines which do it that way, but the cleaner way is the integration of bones into the scene graph: every object in a scene graph usually has a transformation and a skeleton's bones are also just such objects. The transformation is multiplied along the scene graph hierarchy, so every bone counts and none are skipped.

Well, but at the end it doesn't matter much whether there is an additional bone to put in or not, but for usability it would be better if it wasn't necessary.

Posted: **Tue Aug 27, 2024 12:55 pm**

Anyway, if the weight parameter has no effect no matter what you do, it seems like a bug, doesn't it?

Posted: **Tue Aug 27, 2024 4:11 pm**

Caronte3D wrote: Tue Aug 27, 2024 12:55 pm Anyway, if the weight parameter has no effect no matter what you do, it seems like a bug, doesn't it?

Yeah but as miso said the root bone is "special" in PB Ogre as it looks like a pseudo bone which isn't weighted and counts as whole body transformation.

Posted: **Sat Aug 31, 2024 8:38 pm**

Caronte3D wrote: Tue Aug 27, 2024 12:55 pm Anyway, if the weight parameter has no effect no matter what you do, it seems like a bug, doesn't it?

It has effect, but the sum of the weights must be equals 1. Root bone or not, does not matter. When a vertex is affected by multiple bones, you may split the weights between them, but the sum is always 1. With only one affecting bone, you can only have a weight of 1.
For me, still looks like OK.

Yeah but as miso said the root bone is "special" in PB Ogre as it looks like a pseudo bone which isn't weighted and counts as whole body transformation.

It works with the root bone too, its just very wierd for me to use it with weights, and not as a base of the skeleton hierarchy. But one can use it (vertices can be assigned to it), if it fit's better for what's needed.

PureBasic Forums - English

Skeleton-Mesh lib VertexBoneAssignment(), bug?

Skeleton-Mesh lib VertexBoneAssignment(), bug?

Re: Skeleton-Mesh lib VertexBoneAssignment(), bug?

Re: Skeleton-Mesh lib VertexBoneAssignment(), bug?

Re: Skeleton-Mesh lib VertexBoneAssignment(), bug?

Re: Skeleton-Mesh lib VertexBoneAssignment(), bug?

Re: Skeleton-Mesh lib VertexBoneAssignment(), bug?

Re: Skeleton-Mesh lib VertexBoneAssignment(), bug?