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

   1
   2 /*]  Copyright (c) 2009-2011, Charles McGarvey  [*****************************
   3 **]  All rights reserved.
   4 *
   5 * Distributable under the terms and conditions of the 2-clause BSD license;
   6 * see the file COPYING for a complete text of the license.
   7 *
   8 *****************************************************************************/
   9
  10 #ifndef _MOOF_ENTITY_HH_
  11 #define _MOOF_ENTITY_HH_
  12
  13 /**
  14  * \file entity.hh
  15  * Interface class for cullable and drawable objects.
  16  */
  17
  18 #include <boost/shared_ptr.hpp>
  19
  20 #include <moof/aabb.hh>
  21 #include <moof/cullable.hh>
  22 #include <moof/drawable.hh>
  23 #include <moof/sphere.hh>
  24
  25
  26 namespace moof {
  27
  28
  29 // forward declarations
  30 class frustum;
  31
  32 /**
  33  * Interface for game objects that can be drawn to the screen and have a
  34  * specified volume (take up space).
  35  */
  36 class entity : public cullable, public drawable
  37 {
  38 public:
  39
  40         virtual ~entity() {}
  41
  42         /**
  43          * Draw the entity only if it is visible.  This method melds the
  44          * cullable and drawable interfaces, and the default implementation is
  45          * usually on the money.
  46          * \param alpha The fraction between the last timestep and the next
  47          * timestep.
  48          * \param frustum The camera frustum for determining visibility.
  49          */
  50         virtual void
  51         draw_if_visible(scalar alpha, const frustum& frustum) const
  52         {
  53                 if (is_visible(frustum)) draw(alpha);
  54         }
  55
  56         /**
  57          * Get whether or not the entity is within a frustum.  The default
  58          * implementation returns the visibility of the bounding sphere and
  59          * box.
  60          * \param frustum The camera frustum.
  61          * \return True if the entity is visible, false otherwise.
  62          */
  63         virtual bool is_visible(const frustum& frustum) const
  64         {
  65                 return sphere_.is_visible(frustum) && aabb_.is_visible(frustum);
  66         }
  67
  68         /**
  69          * Get the axis-aligned bounding box surrounding the entity.
  70          * \return The AABB.
  71          */
  72         const moof::aabb3& aabb() const
  73         {
  74                 return aabb_;
  75         }
  76
  77         /** Get the bounding sphere surrounding the entity.
  78          * \return The sphere.
  79          */
  80         const moof::sphere3& sphere() const
  81         {
  82                 return sphere_;
  83         }
  84
  85 protected:
  86
  87         moof::aabb3     aabb_;
  88         moof::sphere3   sphere_;
  89 };
  90
  91 typedef boost::shared_ptr<entity> entity_ptr;
  92
  93
  94 } // namespace moof
  95
  96 #endif // _MOOF_ENTITY_HH_
  97