tweening.cpp

#include "prism/tweening.h"

#include <stdio.h>

#include <prism/datastructures.h>
#include <prism/memoryhandler.h>
#include <prism/math.h>
#include <prism/stlutil.h>

using namespace std;

namespace prism {

	typedef struct {
		double* mDst;
		TweeningFunction mFunc;

		double mStart;
		double mEnd;

		Duration mNow;
		Duration mDuration;

		TweeningCBFunction mCB;
		void* mCaller;
	} Tween;

	static struct {
		map<int, Tween> mTweens;
		int mIsActive;
	} gTweening;

	static void unloadTweening(void*);
	static void loadTweening(void*)
	{
		setProfilingSectionMarkerCurrentFunction();

		if (gTweening.mIsActive) {
			unloadTweening(NULL);
		}
		gTweening.mTweens.clear();
		gTweening.mIsActive = 1;
	}

	static void unloadTweening(void*)
	{
		setProfilingSectionMarkerCurrentFunction();
		gTweening.mTweens.clear();
		gTweening.mIsActive = 0;
	}

	static int updateTween(void* tCaller, Tween& tData) {
		(void)tCaller;
		Tween* e = &tData;

		int isOver = handleDurationAndCheckIfOver(&e->mNow, e->mDuration);

		double baseT = getDurationPercentage(e->mNow, e->mDuration);
		double t = e->mFunc(baseT);

		*e->mDst = e->mStart + t * (e->mEnd - e->mStart);

		if (isOver && e->mCB) {
			e->mCB(e->mCaller);
		}

		return isOver;
	}

	static void updateTweening(void*)
	{
		setProfilingSectionMarkerCurrentFunction();
		stl_int_map_remove_predicate(gTweening.mTweens, updateTween);
	}

	ActorBlueprint getTweeningHandler() {
		return makeActorBlueprint(loadTweening, unloadTweening, updateTweening);
	}

	int tweenDouble(double* tDst, double tStart, double tEnd, TweeningFunction tFunc, Duration tDuration, TweeningCBFunction tCB, void* tCaller)
	{
		Tween e;
		e.mDst = tDst;
		e.mStart = tStart;
		e.mEnd = tEnd;
		e.mFunc = tFunc;
		e.mNow = 0;
		e.mDuration = tDuration;
		e.mCB = tCB;
		e.mCaller = tCaller;

		*tDst = tStart;

		return stl_int_map_push_back(gTweening.mTweens, e);
	}

	void removeTween(int tID)
	{
		gTweening.mTweens.erase(tID);
	}

	double linearTweeningFunction(double t) {
		return t;
	}

	double quadraticTweeningFunction(double t) {
		return t * t;
	}

	double inverseQuadraticTweeningFunction(double t) {
		return 1 - quadraticTweeningFunction(1 - t);
	}

	double squareRootTweeningFunction(double t) {
		return sqrt(t);
	}

	double overshootTweeningFunction(double t) {
		double overshoot = 1.5;
		if (t < 0.8) return linearTweeningFunction((t / 0.8) * overshoot);
		else return linearTweeningFunction(overshoot + ((t - 0.8) / 0.2) * (1.0 - overshoot));
	}

	double transformAtEndTweeningFunction(double t)
	{
		if (t >= 1) return 1;
		else return 0;
	}

}