Docstoc

Modeling

Document Sample
Modeling Powered By Docstoc
					       3-D Modeling
Designing in the world of 3-D
Sources
   www.prodesktop.net
   http://www.3dcafe.com
   http://www.transvisioninc.com
   http://www.pixar.com
   http://www.tecso.com.pl/flash/flashindex.html
3d Modeling
   Modeling in 3 dimensions is the future of
    computer design and animations. This
    technology has been available for many
    years, however due to the enormous costs to
    develop, this technology was out of
    affordability range for most companies.

   The uses for 3D design are almost limitless.
Some Common Uses:
   3D development of landmarks even before they are constructed.

   Creating computer animated movies such as Pixar’s toy story.
         http://www.pixar.com/shorts/index.html

   Home builders can show a virtual reality tour of homes before they are
    built or can show buyers how their home looks with the custom options
    they choose.

   Automobile purchasers can see how their car looks with ther selection
    of colors, rims, accessories and additional options before they commit
    to purchasing their vehicle.

   Industry can utilize 3d modeling programs to show clients perspectives
    jobs before completion.
   http://www.tecso.com.pl/flash/flashindex.html
3d Animation
3-D Coordinate Space
   3-D Coordinate Space
   Everything done in a 3d computer application revolves
    around the concept of a 3-d coordinate system.
   Imagine yourself (as difficult as it may be to do) at the very center
    of the universe. There are six directions ranged about you in
    three pairs:
   Left and right--the horizontal or “x” directions.
   Up and down--the vertical or “y” directions.
   Forward and backwards or the “z” directions--for which we have
    no general name.
   Because of gravity, up and down have a physical meaning quite
    distinct from left and right or forward and backward, however we
    must try to throw away our concept of gravity for the use of 3d
    modeling.
Boolean Operations
   Boolean Operations are modeling methods that make use of two
    objects that overlap and therefore share part of the same space.
   In Boolean union, the geometry of the overlapping area is
    eliminated and a single object is created from the two using all of
    the exposed surface area. Union is generally used to merge
    objects that are most easily built from component parts that have
    been modeled separately.
   Boolean subtraction is used to sculpt out the overlapping volume
    from one object or the other. After the operation, one object is
    left, minus its overlapping region with the other object.
   Boolean intersection preserves the overlapping region only,
    eliminating all the rest of both objects.
Boolean Operations Quiz




                           is each picture?
What type




            of operation
Results of Boolean Operations




                                 Boolean Subtraction
Boolean Union




                Boolean Intersection
Model
   In the language of 3-D graphics, a model is a
    data file that contains the information needed
    to view or "render" a 3-D object. This
    information includes two types of information:
   1. The geometry--the shape--of the object.
   2. The surface attributes of the object--
    meaning data that allows the object to be
    properly colored so that it looks like it is made
    of some kind of material (e.g. metal, glass,
    wood, plastic, etc.)
2 Aspects of Modeling



           Geometry




                        Surface
                        Attributes:
                        Varnished Wood
Primitive Solids
   Primitives are the basic 3D geometric shapes that are
    automatically generated by 3D modeling applications, and which
    therefore need not be constructed from scratch. A very
    considerable amount of modeling (perhaps most) begins with
    primitives, which are then edited and used with other primitives to
    create more complex objects.
   All applications provide spheres, cubes, cylinders (sometimes
    called disks) and cones. Some provide a wider array. All
    primitives have parameters that define their size and shape. A
    sphere necessarily has a center point and a radius, though the
    application may also provide for defining the sphere by its x,y
    and z extents--in effect defining the sphere by a cube into which
    the sphere will fit.
Primitive Solids
   Cylinders   Cubes   Prisms/Cones
Rendering
   Rendering is the process of producing images from
    a view of 3-D models in a 3-D scene. It is, in effect,
    "taking a picture" of the scene. An animation is a
    series of such renderings, each with the scene
    slightly changed.
   A camera is placed at a location in a 3-D coordinate
    space, pointing in a given direction. Those polygons
    that fall within the camera's field of view are
    mathematically projected onto a plane, just as a real
    camera projects an image onto film. The rendering
    process necessarily involves some means of
    determining whether a given surface of a model is
    obscured by another surface closer to the camera.
Rendered Block
Common 3d Modeling
Commands:   Extrusion
   Extrusion is the process of creating three-
    dimensional geometry out of flat, two-
    dimensional shapes by drawing the 2-D
    shape along a path in 3-D space. The
    extrusion path may be a straight line or any
    kind of curve. If the path is linear, it may be
    normal to, or at any other angle to the
    extruded shape.
Extrusion
Revolve
   The Revolve command allows you to create a
    curved solid from a 2D object by sweeping it
    around an axis. Revolve can be used with an
    object made from Polygons, Circles, Ellipses,
    and Splines. Objects must have a closed
    path to be revolved.
 Revolve Command




Profile   Axis
Loft Command

   The loft command allows you to create a
    solid object by extruding 2 or more shapes
    offset at a desired distance from each other.
    The shapes may be the same or different to
    use the loft command.
Loft Examples
Sweep Command

   A sketch is swept along a defined path to
    create a surface or solid. Some important
    considerations in sweeps include the relative
    location of the sketch to the sweep path and
    the curvature of the path. The sweep
    command can also be used to create a helix
    or a spring type object.
Sweep Examples



   Path




          Profile

				
DOCUMENT INFO