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How do i solve this specific scene graph problem

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Hi,
 
i have a 2D scene graph.
 
i have object A, object B and transform V.
 
A is a sphere
B is a quad
 
Each object has a radius, either one or two dimension
The radius of each object A and B is in the same space/relationship - in its initial configuration.
 
Each object has a local transformation matrix relative to its parent
 
B is parented to A
B is initially positioned so that it is touching object A to the left side (Negative right translation)
 
A is parented to V
 
V is the root of the graph
V is treated as a view matrix (No projection)
Therefore it may translate and scale V - like a camera
 
All matrices are 3x3
 
Here comes the problem:
 
A will scale and move based on the transform of V
B should never be scaled by any means!
B must still touch the left side even when A scales by V (Radius is initially known for both of them)
 
How do i solve this problem?
Edited by Finalspace

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You can also undo the scale of the parent in the child node. Simplified something along those lines (note that you undo the scale after the translation):

 

M1 * M2 * v = M1 * ( T2 * S1^-1 * R2 * S2 ) * v 

 

IIRC this is what Maya does for the IKJoint:

http://download.autodesk.com/us/maya/2010help/API/class_m_fn_ik_joint.html

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