From 4692375491fb16da59642022c8d7c891d68ba665 Mon Sep 17 00:00:00 2001
From: Nicolay Korslund <korslund@gmail.com>
Date: Tue, 27 Jul 2010 12:12:06 +0200
Subject: [PATCH] Added convenience classes for connecting sound to Ogre

---
 input/clients/ogre_input_capture.hpp  |  6 +--
 sound/clients/ogre_listener_mover.hpp | 69 +++++++++++++++++++++++++++
 sound/clients/ogre_output_updater.hpp | 31 ++++++++++++
 3 files changed, 103 insertions(+), 3 deletions(-)
 create mode 100644 sound/clients/ogre_listener_mover.hpp
 create mode 100644 sound/clients/ogre_output_updater.hpp

diff --git a/input/clients/ogre_input_capture.hpp b/input/clients/ogre_input_capture.hpp
index 6a7beae4d2..2e77dc10b1 100644
--- a/input/clients/ogre_input_capture.hpp
+++ b/input/clients/ogre_input_capture.hpp
@@ -15,15 +15,15 @@ namespace Input {
   {
     Mangle::Input::Driver &driver;
 
-    ExitListener(Mangle::Input::Driver &drv)
+    OgreInputCapture(Mangle::Input::Driver &drv)
       : driver(drv) {}
 
-    bool frameStarted(const FrameEvent &evt)
+    bool frameStarted(const Ogre::FrameEvent &evt)
     {
       driver.capture();
       return true;
     }
   };
-}
+}}
 
 #endif
diff --git a/sound/clients/ogre_listener_mover.hpp b/sound/clients/ogre_listener_mover.hpp
new file mode 100644
index 0000000000..d1cfcb65ce
--- /dev/null
+++ b/sound/clients/ogre_listener_mover.hpp
@@ -0,0 +1,69 @@
+#ifndef MANGLE_SOUND_OGRELISTENERMOVER_H
+#define MANGLE_SOUND_OGRELISTENERMOVER_H
+
+#include <OgreCamera.h>
+#include <assert.h>
+#include "../output.hpp"
+
+namespace Mangle {
+namespace Sound {
+
+  /** This class lets a sound listener (ie. the SoundFactory) track a
+      given camera in Ogre3D. The poisition and orientation of the
+      listener will be updated to match the camera whenever the camera
+      is moved.
+   */
+  struct OgreListenerMover : Ogre::Camera::Listener
+  {
+    OgreListenerMover(Mangle::Sound::SoundFactoryPtr snd)
+      : soundFact(snd), camera(NULL)
+    {}
+
+    /// Follow a camera. WARNING: This will OVERRIDE any other
+    /// MovableObject::Listener you may have attached to the camera.
+    void followCamera(Ogre::Camera *cam)
+    {
+      camera = cam;
+      camera->addListener(this);
+    }
+
+  private:
+    Mangle::Sound::SoundFactoryPtr soundFact;
+    Ogre::Camera *camera;
+    Ogre::Vector3 pos, dir, up;
+
+    /// From Camera::Listener. This is called once per
+    /// frame. Unfortunately, Ogre doesn't allow us to be notified
+    /// only when the camera itself has moved, so we must poll every
+    /// frame.
+    void cameraPreRenderScene(Ogre::Camera *cam)
+    {
+      assert(cam == camera);
+
+      Ogre::Vector3 nPos, nDir, nUp;
+
+      nPos = camera->getPosition();
+      nDir = camera->getDirection();
+      nUp  = camera->getUp();
+
+      // Don't bother the sound system needlessly
+      if(nDir != dir || nPos != pos || nUp != up)
+        {
+          pos = nPos;
+          dir = nDir;
+          up  = nUp;
+
+          soundFact->setListenerPos(pos.x, pos.y, pos.z,
+                                    dir.x, dir.y, dir.z,
+                                    up.x, up.y, up.z);
+        }
+    }
+
+    void cameraDestroyed(Ogre::Camera *cam)
+    {
+      assert(cam == camera);
+      camera = NULL;
+    }
+  };
+}}
+#endif
diff --git a/sound/clients/ogre_output_updater.hpp b/sound/clients/ogre_output_updater.hpp
new file mode 100644
index 0000000000..5072e9f1e8
--- /dev/null
+++ b/sound/clients/ogre_output_updater.hpp
@@ -0,0 +1,31 @@
+#ifndef MANGLE_SOUND_OGREUPDATER_H
+#define MANGLE_SOUND_OGREUPDATER_H
+
+/*
+  This Ogre FrameListener calls update on a SoundFactory
+ */
+
+#include <OgreFrameListener.h>
+#include "../output.hpp"
+#include <assert.h>
+
+namespace Mangle {
+namespace Sound {
+
+  struct OgreOutputUpdater : Ogre::FrameListener
+  {
+    Mangle::Sound::SoundFactory &driver;
+
+    OgreOutputUpdater(Mangle::Sound::SoundFactory &drv)
+      : driver(drv)
+    { assert(drv.needsUpdate); }
+
+    bool frameStarted(const Ogre::FrameEvent &evt)
+    {
+      driver.update();
+      return true;
+    }
+  };
+}}
+
+#endif