Engine directory for ticket #1

Engine/source/forest/forestWindAccumulator.h

@@ -0,0 +1,79 @@
+//-----------------------------------------------------------------------------
+// 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.
+//-----------------------------------------------------------------------------
+
+#ifndef _FORESTWINDACCUMULATOR_H_
+#define _FORESTWINDACCUMULATOR_H_
+
+#ifndef _MPOINT3_H_
+#include "math/mPoint3.h"
+#endif
+
+
+struct TreePlacementInfo;
+class ForestItemData;
+
+
+/// This simple class holds the state of the accumulated 
+/// wind effect for a single tree.
+class ForestWindAccumulator
+{
+protected:
+
+   struct VerletParticle
+   {
+      Point2F position;
+      Point2F lastPosition;
+   };
+
+   F32 mCurrentStrength;
+   Point2F mCurrentDir;
+
+   Point3F mPosition;
+   F32 mScale;
+   ForestItemData *mDataBlock;
+
+   VerletParticle mParticles[2];
+
+   void _updateParticle( VerletParticle *particle, const Point2F &force, F32 timeDelta );
+
+public:
+
+   ForestWindAccumulator( const TreePlacementInfo &info );
+   ~ForestWindAccumulator();
+
+   void presimulate( const VectorF &windVector, U32 ticks );
+
+   void updateWind( const VectorF &windVector, F32 timeDelta );
+
+   void setDirection( const VectorF &dir ) { mCurrentDir.set( dir.x, dir.y ); }
+   VectorF getDirection() const { return VectorF( mCurrentDir.x, mCurrentDir.y, 0 ); }
+
+   void setStrength( F32 strength ) { mCurrentStrength = strength; }
+   F32 getStrength() const { return mCurrentStrength; }
+
+   void setPosition( const Point3F &pos ) { mPosition = pos; }
+   Point3F getPosition() const { return mPosition; }
+
+   void applyImpulse( const VectorF &impulse );
+};
+
+#endif // _FORESTWINDACCUMULATOR_H_