Class ObjectFile

  • All Implemented Interfaces:
    Loader

    public class ObjectFile
    extends java.lang.Object
    implements Loader
    The ObjectFile class implements the Loader interface for the Wavefront .obj file format, a standard 3D object file format created for use with Wavefront's Advanced Visualizer (tm) and available for purchase from Viewpoint DataLabs, as well as other 3D model companies. Object Files are text based files supporting both polygonal and free-form geometry (curves and surfaces). The Java 3D .obj file loader supports a subset of the file format, but it is enough to load almost all commonly available Object Files. Free-form geometry is not supported.

    The Object File tokens currently supported by this loader are:

    v float float float

    A single vertex's geometric position in space. The first vertex listed in the file has index 1, and subsequent vertices are numbered sequentially.

    vn float float float

    A normal. The first normal in the file is index 1, and subsequent normals are numbered sequentially.

    vt float float

    A texture coordinate. The first texture coordinate in the file is index 1, and subsequent normals are numbered sequentially.

    f int int int . . .

    or

    f int/int int/int int/int . . .

    or

    f int/int/int int/int/int int/int/int . . .

    A polygonal face. The numbers are indexes into the arrays of vertex positions, texture coordinates, and normals respectively. There is no maximum number of vertices that a single polygon may contain. The .obj file specification says that each face must be flat and convex, but if the TRIANGULATE flag is sent to the ObjectFile constructor, each face will be triangulated by the Java 3D Triangulator, and therefore may be concave. A number may be omitted if, for example, texture coordinates are not being defined in the model. Numbers are normally positive indexes, but may also be negative. An index of -1 means the last member added to the respective array, -2 is the one before that, and so on.

    g name

    Faces defined after this token will be added to the named group. These geometry groups are returned as separated Shape3D objects attached to the parent SceneGroup. Each named Shape3D will also be in the Hashtable returned by Scene.getNamedObjects(). It is legal to add faces to a group, switch to another group, and then add more faces to the original group by reissuing the same name with the g token. If faces are added to the model before the g token is seen, the faces are put into the default group called "default."

    s int

    or

    s off

    If the vn token is not used in the file to specify vertex normals for the model, this token may be used to put faces into groups for normal calculation ("smoothing groups") in the same manner as the 'g' token is used to group faces geometrically. Faces in the same smoothing group will have their normals calculated as if they are part of the same smooth surface. To do this, we use the Java 3D NormalGenerator utility with the creaseAngle parameter set to PI (180 degrees - smooth shading, no creases) or to whatever the user has set the creaseAngle. Faces in group 0 or 'off' use a creaseAngle of zero, meaning there is no smoothing (the normal of the face is used at all vertices giving the surface a faceted look; there will be a crease, or "Hard Edge," between each face in group zero). There is also an implied hard edge between each smoothing group, where they meet each other.

    If neither the vn nor the s token is used in the file, then normals are calculated using the creaseAngle set in the contructor. Normals are calculated on each geometry group separately, meaning there will be a hard edge between each geometry group.

    usemtl name

    The current (and subsequent) geometry groups (specified with the 'g' token) have applied to them the named material property. The following set of material properties are available by default:

         amber           amber_trans       aqua            aqua_filter
         archwhite       archwhite2        bflesh          black
         blondhair       blue_pure         bluegrey        bluetint
         blugrn          blutan            bluteal         bone
         bone1           bone2             brass           brnhair
         bronze          brown             brownlips       brownskn
         brzskin         chappie           charcoal        deepgreen
         default         dkblue            dkblue_pure     dkbrown
         dkdkgrey        dkgreen           dkgrey          dkorange
         dkpurple        dkred             dkteal          emerald
         fgreen          flaqua            flblack         flblonde
         flblue_pure     flbrown           fldkblue_pure   fldkdkgrey
         fldkgreen       fldkgreen2        fldkgrey        fldkolivegreen
         fldkpurple      fldkred           flesh           fleshtransparent
         flgrey          fllime            flltbrown       flltgrey
         flltolivegreen  flmintgreen       flmustard       florange
         flpinegreen     flpurple          flred           fltan
         flwhite         flwhite1          flyellow        glass
         glassblutint    glasstransparent  gold            green
         greenskn        grey              hair            iris
         jetflame        lavendar          lcdgreen        lighttan
         lighttan2       lighttan3         lighttannew     lightyellow
         lime            lips              ltbrown         ltgrey
         meh             metal             mintgrn         muscle
         navy_blue       offwhite.cool     offwhite.warm   olivegreen
         orange          pale_green        pale_pink       pale_yellow
         peach           periwinkle        pink            pinktan
         plasma          purple            red             redbrick
         redbrown        redorange         redwood         rubber
         ruby            sand_stone        sapphire        shadow
         ship2           silver            skin            sky_blue
         smoked_glass    tan               taupe           teeth
         violet          white             yellow          yellow_green
         yellowbrt       yelloworng
       
    mtllib filename

    Load material properties from the named file. Materials with the same name as the predefined materials above will override the default value. Any directory path information in (filename) is ignored. The .mtl files are assumed to be in the same directory as the .obj file. If they are in a different directory, use Loader.setBasePath() (or Loader.setBaseUrl() ). The format of the material properties files are as follows:

    newmtl name

    Start the definition of a new named material property.

    Ka float float float

    Ambient color.

    Kd float float float

    Diffuse color.

    Ks float float float

    Specular color.

    illum (0, 1, or 2)

    0 to disable lighting, 1 for ambient & diffuse only (specular color set to black), 2 for full lighting.

    Ns float

    Shininess (clamped to 1.0 - 128.0).

    map_Kd filename

    Texture map. Supports .rgb, .rgba, .int, .inta, .sgi, and .bw files in addition to those supported by TextureLoader.

    • Constructor Summary

      Constructors 
      Constructor Description
      ObjectFile()
      Default constructor.
      ObjectFile​(int flags)
      Constructor.
      ObjectFile​(int flags, float radians)
      Constructor.
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      java.lang.String getBasePath()
      Return the path where files associated with this .obj file (like material files) are located.
      java.net.URL getBaseUrl()
      Return the URL where files associated with this .obj file (like material properties files) will be found.
      int getFlags()
      Get the parameters currently defined for loading the model.
      Scene load​(java.io.Reader reader)
      The Object File is loaded from the already opened file.
      Scene load​(java.lang.String filename)
      The Object File is loaded from the .obj file specified by the filename.
      Scene load​(java.net.URL url)
      The object file is loaded off of the web.
      void setBasePath​(java.lang.String pathName)
      Set the path where files associated with this .obj file are located.
      void setBaseUrl​(java.net.URL url)
      For an .obj file loaded from a URL, set the URL where associated files (like material properties files) will be found.
      void setFlags​(int flags)
      Set parameters for loading the model.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • RESIZE

        public static final int RESIZE
        Flag sent to constructor. The object's vertices will be changed so that the object is centered at (0,0,0) and the coordinate positions are all in the range of (-1,-1,-1) to (1,1,1).
        See Also:
        Constant Field Values
      • TRIANGULATE

        public static final int TRIANGULATE
        Flag sent to constructor. The Shape3D object will be created by using the GeometryInfo POLYGON_ARRAY primitive, causing them to be Triangulated by GeometryInfo. Use this if you suspect concave or other non-behaving polygons in your model.
        See Also:
        Constant Field Values
      • REVERSE

        public static final int REVERSE
        Flag sent to constructor. Use if the vertices in your .obj file were specified with clockwise winding (Java 3D wants counter-clockwise) so you see the back of the polygons and not the front. Calls GeometryInfo.reverse().
        See Also:
        Constant Field Values
      • STRIPIFY

        public static final int STRIPIFY
        Flag sent to contructor. After normals are generated the data will be analyzed to find triangle strips. Use this if your hardware supports accelerated rendering of strips.
        See Also:
        Constant Field Values
    • Constructor Detail

      • ObjectFile

        public ObjectFile​(int flags,
                          float radians)
        Constructor.
        Parameters:
        flags - The constants from above or from com.sun.j3d.loaders.Loader, possibly "or'ed" (|) together.
        radians - Ignored if the vn token is present in the model (user normals supplied). Otherwise, crease angle to use within smoothing groups, or within geometry groups if the s token isn't present either.
      • ObjectFile

        public ObjectFile​(int flags)
        Constructor. Crease Angle set to default of 44 degrees (see NormalGenerator utility for details).
        Parameters:
        flags - The constants from above or from com.sun.j3d.loaders.Loader, possibly "or'ed" (|) together.
      • ObjectFile

        public ObjectFile()
        Default constructor. Crease Angle set to default of 44 degrees (see NormalGenerator utility for details). Flags set to zero (0).
    • Method Detail

      • load

        public Scene load​(java.lang.String filename)
                   throws java.io.FileNotFoundException,
                          IncorrectFormatException,
                          ParsingErrorException
        The Object File is loaded from the .obj file specified by the filename. To attach the model to your scene, call getSceneGroup() on the Scene object passed back, and attach the returned BranchGroup to your scene graph. For an example, see j3d-examples/ObjLoad/ObjLoad.java.
        Specified by:
        load in interface Loader
        Throws:
        java.io.FileNotFoundException
        IncorrectFormatException
        ParsingErrorException
      • setBaseUrl

        public void setBaseUrl​(java.net.URL url)
        For an .obj file loaded from a URL, set the URL where associated files (like material properties files) will be found. Only needs to be called to set it to a different URL from that containing the .obj file.
        Specified by:
        setBaseUrl in interface Loader
      • getBaseUrl

        public java.net.URL getBaseUrl()
        Return the URL where files associated with this .obj file (like material properties files) will be found.
        Specified by:
        getBaseUrl in interface Loader
      • setBasePath

        public void setBasePath​(java.lang.String pathName)
        Set the path where files associated with this .obj file are located. Only needs to be called to set it to a different directory from that containing the .obj file.
        Specified by:
        setBasePath in interface Loader
      • getBasePath

        public java.lang.String getBasePath()
        Return the path where files associated with this .obj file (like material files) are located.
        Specified by:
        getBasePath in interface Loader
      • setFlags

        public void setFlags​(int flags)
        Set parameters for loading the model. Flags defined in Loader.java are ignored by the ObjectFile Loader because the .obj file format doesn't include lights, fog, background, behaviors, views, or sounds. However, several flags are defined specifically for use with the ObjectFile Loader (see above).
        Specified by:
        setFlags in interface Loader
      • getFlags

        public int getFlags()
        Get the parameters currently defined for loading the model. Flags defined in Loader.java are ignored by the ObjectFile Loader because the .obj file format doesn't include lights, fog, background, behaviors, views, or sounds. However, several flags are defined specifically for use with the ObjectFile Loader (see above).
        Specified by:
        getFlags in interface Loader