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3D object represent with primitive shapes

  1. Sep 16, 2015 #1
    Hi,
    Given a 3D object in R3 space can we represent it using three basic primitive shapes like Sphere, Cone and Cylinder? Would this claim be valid?
     
  2. jcsd
  3. Sep 16, 2015 #2

    Orodruin

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  4. Sep 16, 2015 #3
    Hi Orodruin,

    Can you be more clear. Why No and isn't it write to represent 3D objects into any primitive shapes.
     
  5. Sep 16, 2015 #4

    Orodruin

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    It is not very clear what you mean by "representing 3D objects into primitive shapes".
     
  6. Sep 16, 2015 #5
    I am trying to decompose 3D object (eg. Bunny) into primitive shapes basis functions.
     
  7. Sep 16, 2015 #6

    Nidum

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    Depends on whether you mean in a strict mathematical sense or in a practical representation sense .

    (1) Real 3D objects of great complexity can be accurately represented by assemblies of simple units like tetrahedrons . This is one of the basic principles of finite element analysis and some types of 3D CAD .

    Tetrahedrons and other primitive shapes like cubes can be used in a basic way or they can be systematically deformed to give a higher level of accuracy .

    Some examples : http://www.truegrid.com/fe.html

    (2) At a more artistic level complex 3D shapes can be represented by assemblies of basic units taken from a big selection of basic units - anything from simple cubes to arms, legs bugs and spaceships . Again these objects can be deliberately distorted as required .

    Fun to play with : https://www.tinkercad.com/



     
    Last edited: Sep 16, 2015
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