Dogcows Code - chaz/yoink/blob - src/moof/entity.hh

   1
   2 /*]  Copyright (c) 2009-2010, Charles McGarvey  [**************************
   3 **]  All rights reserved.
   4 *
   5 * vi:ts=4 sw=4 tw=75
   6 *
   7 * Distributable under the terms and conditions of the 2-clause BSD license;
   8 * see the file COPYING for a complete text of the license.
   9 *
  10 **************************************************************************/
  11
  12 #ifndef _MOOF_ENTITY_HH_
  13 #define _MOOF_ENTITY_HH_
  14
  15 /**
  16  * \file entity.hh
  17  * Interface class for cullable and drawable objects.
  18  */
  19
  20 #include <boost/shared_ptr.hpp>
  21
  22 #include <moof/aabb.hh>
  23 #include <moof/cullable.hh>
  24 #include <moof/drawable.hh>
  25 #include <moof/sphere.hh>
  26
  27
  28 namespace moof {
  29
  30
  31 class frustum;
  32
  33
  34 class entity;
  35
  36 /**
  37  * Entity pointer.
  38  */
  39 typedef boost::shared_ptr<entity> entity_ptr;
  40
  41
  42 /**
  43  * Interface for game objects that can be drawn to the screen and have a
  44  * specified volume (take up space).
  45  */
  46 class entity : public cullable, public drawable
  47 {
  48 public:
  49
  50         virtual ~entity() {}
  51
  52         /**
  53          * Draw the entity only if it is visible.  This method melds the
  54          * cullable and drawable interfaces, and the default implementation is
  55          * usually on the money.
  56          * \param alpha The fraction between the last timestep and the next
  57          * timestep.
  58          * \param frustum The camera frustum for determining visibility.
  59          */
  60         virtual void draw_if_visible(scalar alpha, const frustum& frustum) const
  61         {
  62                 if (is_visible(frustum)) draw(alpha);
  63         }
  64
  65         /**
  66          * Get whether or not the entity is within a frustum.  The default
  67          * implementation returns the visibility of the bounding sphere and
  68          * box.
  69          * \param frustum The camera frustum.
  70          * \return True if the entity is visible, false otherwise.
  71          */
  72         virtual bool is_visible(const frustum& frustum) const
  73         {
  74                 return sphere_.is_visible(frustum) && aabb_.is_visible(frustum);
  75         }
  76
  77
  78         /**
  79          * Get the axis-aligned bounding box surrounding the entity.
  80          * \return The AABB.
  81          */
  82         const moof::aabb<3>& aabb() const
  83         {
  84                 return aabb_;
  85         }
  86
  87         /** Get the bounding sphere surrounding the entity.
  88          * \return The sphere.
  89          */
  90         const moof::sphere<3>& sphere() const
  91         {
  92                 return sphere_;
  93         }
  94
  95
  96 protected:
  97
  98         moof::aabb<3>   aabb_;
  99         moof::sphere<3> sphere_;
 100 };
 101
 102
 103 } // namespace moof
 104
 105 #endif // _MOOF_ENTITY_HH_
 106