tbx_tweening_behavior.hpp

#ifndef TurtleBrainsExpress_TweeningBehavior_hpp
#define TurtleBrainsExpress_TweeningBehavior_hpp

#include <turtle_brains/game/tb_entity_behavior_interface.hpp>
#include <turtle_brains/game/tb_game_timer.hpp>
#include <turtle_brains/math/tb_interpolation.hpp>

namespace TurtleBrainsExpress
{
    namespace Behaviors
    {
        typedef tbMath::Interpolation::InterpolationMode TweenMode;

        template <typename Type> class TweeningBehavior : public tbGame::EntityBehaviorInterface
        {
        public:
            TweeningBehavior(tbGame::Entity& entity, const Type& startValue, const Type& finalValue,
                const tbGame::GameTimer& time, const TweenMode& tweenMode) :
                tbGame::EntityBehaviorInterface(entity),
                mFinalValue(finalValue),
                mStartValue(startValue),
                mMaximumTime(time),
                mTimer(time),
                mTweenMode(tweenMode)
            {
            }

            virtual ~TweeningBehavior(void)
            {
            }

        protected:
            inline void SetStartValue(const Type& startValue)
            {
                mStartValue = startValue;
            }

            inline Type GetCurrentTweenValue(void) const
            {
                if (true == mTimer.IsZero())
                {
                    return mFinalValue;
                }

                const float percentage(1.0f - mTimer.GetPercentageOf(mMaximumTime));
                return tbMath::Interpolation::Interpolate(percentage, mStartValue, mFinalValue, mTweenMode);
            }

            inline virtual void OnRemove(void) override
            {
                mTimer = 0;
                tbGame::EntityBehaviorInterface::OnRemove();
            }

            inline virtual void OnSimulate(void) override
            {
                if (true == mTimer.DecrementStep())
                {
                    mEntity.PopBehavior();
                }

                tbGame::EntityBehaviorInterface::OnSimulate();
            }

        private:
            const Type mFinalValue;
            Type mStartValue;
            const tbGame::GameTimer mMaximumTime;
            tbGame::GameTimer mTimer;
            const TweenMode mTweenMode;
        };

    }; /* namespace Behaviors */
}; /* namespace TurtleBrainsExpress */

namespace tbxBehaviors = TurtleBrainsExpress::Behaviors;

#endif /* TurtleBrainsExpress_TweeningBehavior_hpp */