Engine directory for ticket #1

Engine/source/core/iTickable.cpp

@@ -0,0 +1,111 @@
+//-----------------------------------------------------------------------------
+// Copyright (c) 2012 GarageGames, LLC
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//-----------------------------------------------------------------------------
+
+#include "core/iTickable.h"
+
+// The statics
+U32 ITickable::smLastTick = 0;
+U32 ITickable::smLastTime = 0;
+U32 ITickable::smLastDelta = 0;
+
+U32 ITickable::smTickShift = 5;
+U32 ITickable::smTickMs = ( 1 << smTickShift );
+F32 ITickable::smTickSec = ( F32( ITickable::smTickMs ) / 1000.f );
+U32 ITickable::smTickMask = ( smTickMs - 1 );
+
+//------------------------------------------------------------------------------
+
+ITickable::ITickable() : mProcessTick( true )
+{
+   getProcessList().push_back( this );
+}
+
+//------------------------------------------------------------------------------
+
+ITickable::~ITickable()
+{
+   for( ProcessListIterator i = getProcessList().begin(); i != getProcessList().end(); i++ )
+   {
+      if( (*i) == this )
+      {
+         getProcessList().erase( i );
+         return;
+      }
+   }
+}
+
+//------------------------------------------------------------------------------
+
+void ITickable::init( const U32 tickShift )
+{
+    // Sanity!
+    AssertFatal( tickShift == 0 || tickShift <= 31, "ITickable::init() - Invalid 'tickShift' parameter!" );
+
+    // Calculate tick constants.
+    smTickShift = tickShift;
+    smTickMs = ( 1 << smTickShift );
+    smTickSec = ( F32( smTickMs ) / 1000.f );
+    smTickMask = ( smTickMs - 1 );
+}
+
+//------------------------------------------------------------------------------
+
+Vector<ITickable *>& ITickable::getProcessList()
+{
+   // This helps to avoid the static initialization order fiasco
+   static Vector<ITickable *> smProcessList( __FILE__, __LINE__ ); ///< List of tick controls
+   return smProcessList;
+}
+
+//------------------------------------------------------------------------------
+
+bool ITickable::advanceTime( U32 timeDelta )
+{
+   U32 targetTime = smLastTime + timeDelta;
+   U32 targetTick = ( targetTime + smTickMask ) & ~smTickMask;
+   U32 tickCount = ( targetTick - smLastTick ) >> smTickShift;
+
+   // Advance objects
+   if( tickCount )
+      for( ; smLastTick != targetTick; smLastTick += smTickMs )
+         for( ProcessListIterator i = getProcessList().begin(); i != getProcessList().end(); i++ )
+            if( (*i)->isProcessingTicks() )
+               (*i)->processTick();
+
+   smLastDelta = ( smTickMs - ( targetTime & smTickMask ) ) & smTickMask;
+   F32 dt = smLastDelta / F32( smTickMs );
+
+   // Now interpolate objects that want ticks
+   for( ProcessListIterator i = getProcessList().begin(); i != getProcessList().end(); i++ )
+      if( (*i)->isProcessingTicks() )
+         (*i)->interpolateTick( dt );
+
+
+   // Inform ALL objects that time was advanced
+   dt = F32( timeDelta ) / 1000.f;
+   for( ProcessListIterator i = getProcessList().begin(); i != getProcessList().end(); i++ )
+      (*i)->advanceTime( dt );
+
+   smLastTime = targetTime;
+
+   return tickCount != 0;
+}