[X3D-Public] Question about Viewport node

[Joe D Williams]

----- Original Message ----- 
From: "Alexander Dong Back Kim" <alexdbkim at gmail.com>
To: <x3d-public at web3d.org>
Sent: Friday, September 04, 2009 8:38 PM
Subject: [X3D-Public] Question about Viewport node


Hi all,

I'm reading the X3D specification and bit confused in the Viewport 
part.

Viewport : X3DGroupingNode, X3DBoundedObject {
  MFNode  [in]     addChildren             [X3DChildNode]
  MFNode  [in]     removeChildren          [X3DChildNode]
  MFNode  [in,out] children       []       [X3DChildNode]
  MFFloat [in,out] clipBoundary   0 1 0 1  [0,1]
  SFNode  [in,out] metadata       NULL     [X3DMetadataObject]
  SFVec3f []       bboxCenter     0 0 0    (-∞,∞)
  SFVec3f []       bboxSize       -1 -1 -1 (0,∞) or -1 -1 -1
}

As you can see there Viewport is inheretied from both X3DGroupingNode 
and
X3DBoundedObject. However, X3DGroupingNode is already a sub class of
X3DBoundedObject.

X3DGroupingNode : X3DChildNode, X3DBoundedObject {
  MFNode  [in]     addChildren             [X3DChildNode]
  MFNode  [in]     removeChildren          [X3DChildNode]
  MFNode  [in,out] children       []       [X3DChildNode]
  SFNode  [in,out] metadata       NULL     [X3DMetadataObject]
  SFVec3f []       bboxCenter     0 0 0    (-∞,∞)
  SFVec3f []       bboxSize       -1 -1 -1 [0,∞) or −1 −1 −1
}


I believe this means the Viewport node shouldn't have included
X3DBoundedObject as a super class in the specification since it is 
already
inherited by X3DGroupingNode which is a super class of Viewport.

If my understanding is wrong, please correct me. Thank you very much.

Regards,
Alexander Dong Back Kim



Hi Alexander,
Good thinking on this. Also looking at:


http://www.web3d.org/x3d/specifications/ISO-IEC-19775-1.2-X3D-AbstractSpecification/Part01/concepts.html#f-Objecthierarchy


Figure 4.2 —

  +- X3DGroupingNode (X3DBoundedObject)* -+- X3DViewportNode -+- 
Viewport

which I think is correct. So

Viewport : X3DViewportNode {
  MFNode     [in]     addChildren                [X3DChildNode]
  MFNode     [in]     removeChildren             [X3DChildNode]
  MFNode     [in,out] children       []          [X3DChildNode]
  MFFloat    [in,out] clipBoundary   0 100 0 100 (0,100)
  SFNode     [in,out] metadata       NULL        [X3DMetadataObject]
  SFVec3f    []       bboxCenter     0 0 0       (-∞,∞)
  SFVec3f    []       bboxSize       -1 -1 -1    (0,∞) or -1 -1 -1
}

along with

X3DViewportNode : X3DGroupingNode {
  MFNode  [in]     addChildren             [X3DChildNode]
  MFNode  [in]     removeChildren          [X3DChildNode]
  MFNode  [in,out] children       []       [X3DChildNode]
  SFNode  [in,out] metadata       NULL     [X3DMetadataObject]
  SFVec3f []       bboxCenter     0 0 0    (-∞,∞)
  SFVec3f []       bboxSize       -1 -1 -1 (0,∞) or -1 -1 -1
}


seems more correct and Viewport text should be updated. .

http://www.web3d.org/x3d/specifications/ISO-IEC-19775-1.2-X3D-AbstractSpecification/Part01/components/layering.html#Viewport

Thanks Again and Best Regards,
Joe