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/home/tetron/hack/vos/apps/tutorials/vostut8creature.hh

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/* Eighth VOS tutorial.  Creating your own MetaObjects II

   This tutorial file covers:
   - Creating simple metaobjects that contain Properties
   - Creating a metaobject for a subtype
   - Vobjects with more than one type
   - A first glimpse at A3DL

   This file (vostut8creature.hh) is released into the public domain.  No
   restrictions are placed on its use, distribution or inclusion into
   other works.
*/

#ifndef _VOSTUT8_CREATURE_HH_
#define _VOSTUT8_CREATURE_HH_

#include <string>
#include <vos/vos/vos.hh>

/* In this tutorial we demonstrate a common metaobject pattern, which
   turns out to actually be simpler than the metaobject created in
   tutorial 7.  These metaobjects will be used as part of a (very tiny)
   database of animals.  It will simply have a certain set of Property
   objects as children, which together will describe a species of animal
   or plant and it's relation to other animals and plants. You could
   create such objects and modify its properties without a special
    metaobject class fairly easily, but it can be convenient
   and improve maintainability to abstract the object type and provide
   a specialized API.

   Furthermore, in this tutorial we will see how to make a Vobject with
    more than one MetaObject type, specifically, 3D object types.

   After reviewing this metaobject's header (vostut8creature.hh), take
   a look at it's implementation (vostut8creature.cc), then on to
   the "server" (vostut8server.cc). After running the server, connect
   to it with mesh and look around.

   This file declares two metaobjects.  One is called Creature, which we
   will use for all living things.  The second is called Animal and contains
   some properties specific to animals.

   The properties of Creature are:
    * Genus
    * Species
    * Common Name
    * Description
    * Image

   Creatures have predators, that is, creatures that eat them. We will
   use Hypercard objects to create indirect links to those predator creatures.
   Any number of predator hypercards will be allowed.

   The properties of Animal are:
    * Range

   Animals have prey, that is, creatures that they eat. We will use
   Hypercard objects to create indirect links to those creature objects.
   Any number of prey hypercards will be allowed.

   After looking through this tutorial, try expanding it. Here are some
   suggestions:

    Excersise 1: Add a new property or properties to Creature that describes
        the creature's usual habitat (whether, terrain, etc.). Give the
        examples in vostut8server.cc values for their habitat properties.

    Excercise 2: Create a new MetaObject which is a subtype of Creature
        to represent Plants. Modify vostut8server.cc to create some plants.

    Excersise 3: Create a new MetaObject which will contain groups of animals.
        Examples of such groups are Mammals, Trees, Fungi, Insects. These
        group MetaObjects will contain Creature objects as children.
        Modify vostut8server.cc to place your plants and animals in groups.

    Excersise 4: In addition to Creatures and 3D Models, let's have these
        objects also form a Hypertext: use the HyperVOS types to form
        a set of web pages about the creatures.

    From here you could build a proper taxonomic structure, you could
    implement some algorithm for positioning the 3D models for each
    creature according to its taxonomic structure, or position in a food
    chain.   You could build a model ecosystem and watch it move and change.

    The only limit is your imagination!

*/

/* These macros are a bit esoteric: they force any program which #includes
   this header file to also perfrom any deferred linking of this
   library, and static initialization of the factory registration objects.
   The argument to this macro MUST match the argument to the BEGIN_ and
   END_REGISTER_METAOBJECT_FACTORIES macros used in vostut8creature.cc.
*/
//IMPORT_METAOBJECT_FACTORIES(CreaturesEtc)

/* Since this class is simply a container for properties, its local
   and remote behaviors will be identical. Therefore we only need one
   class for local and remote objects */
class Creature : public VOS::MetaObject
{
protected:
    Creature(VOS::VobjectBase* superobject);


public:
    virtual const std::string getVOSType();

    /* Set genus */
    void setGenus(const std::string& value);

    /* Get genus */
    void getGenus(std::string& value);

    /* Set species */
    void setSpecies(const std::string& value);

    /* Get species */
    void getSpecies(std::string& value);

    /* Set common name */
    void setCommonName(const std::string& value);

    /* Get common name */
    void getCommonName(std::string& value);

    /* Set description */
    void setDescription(const std::string& value, const std::string& datatype = "string");

    /* Get description */
    void getDescription(std::string& value, std::string& datatype);

    /* Set image data */
    void setImage(const std::string& data, const std::string& datatype = "image/jpeg");

    /* Get image data */
    void getImage(std::string& value, std::string& datatype);

    /* Add a pedator (something that eats this creature) */
    void addPredator(Creature* p);

    /** Set length (cm) */
    void setLength(double l);

    /** Get length */
    double getLength();

    static VOS::MetaObject* new_Creature(VOS::VobjectBase* superobject,
        const std::string& type);
};


class Animal : public Creature
{
protected:

    Animal(VOS::VobjectBase* superobject);

public:

    /** Set length of animal's tail (cm). (Default is 0) */
    void setTailLength(double l);

    /** Get tail length */
    double getTailLength();

    /** Add prey (something that this animal eats) */
    void addPrey(Creature* p);

    virtual const std::string getVOSType();

    static VOS::MetaObject* new_Animal(VOS::VobjectBase* superobject,
        const std::string& type);
};


#endif