c++ Easing code

1. Easing Code

 Many games and App use Easing Algorithm like scrolling, character moving, etc. Blow show c++ code of Easing Algorithm.

start_value : 0 frame's value.

change_value : End frame's value - start_value

inline float easeLinear(float current_frame, float start_value, float end_frame, float change_value)
{
	return change_value*current_frame/end_frame + start_value;
}

inline float easeQuadraticIn(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame;
	return change_value*current_frame*current_frame + start_value;
}

inline float easeQuadraticOut(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame;
	return -change_value * current_frame*(current_frame-2) + start_value;
}

inline float easeQuadraticInOut(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame/2;
	if (current_frame < 1)
		return change_value/2*current_frame*current_frame + start_value;
	current_frame--;
	return -change_value/2 * (current_frame*(current_frame-2) - 1) + start_value;
}

inline float easeCubicIn(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame;
	return change_value*current_frame*current_frame*current_frame + start_value;
}

inline float easeCubicOut(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame;
	current_frame--;
	return change_value*(current_frame*current_frame*current_frame + 1) + start_value;
}

inline float easeCubicInOut(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame/2;
	if (current_frame < 1)
		return change_value/2*current_frame*current_frame*current_frame + start_value;
	current_frame -= 2;
	return change_value/2*(current_frame*current_frame*current_frame + 2) + start_value;
}

inline float easeQuarticIn(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame;
	return change_value*current_frame*current_frame*current_frame*current_frame + start_value;
}

inline float easeQuarticOut(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame;
	current_frame--;
	return -change_value * (current_frame*current_frame*current_frame*current_frame - 1) + start_value;
}

inline float easeQuarticInOut(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame/2;
	if (current_frame < 1)
		return change_value/2*current_frame*current_frame*current_frame*current_frame + start_value;
	current_frame -= 2;
	return -change_value/2 * (current_frame*current_frame*current_frame*current_frame - 2) + start_value;
}

inline float easeQuinticIn(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame;
	return change_value*current_frame*current_frame*current_frame*current_frame*current_frame + start_value;
}

inline float easeQuinticOut(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame;
	current_frame--;
	return change_value*(current_frame*current_frame*current_frame*current_frame*current_frame + 1) + start_value;
}

inline float easeQuinticInOut(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame/2;
	if (current_frame < 1)
		return change_value/2*current_frame*current_frame*current_frame*current_frame*current_frame + start_value;
	current_frame -= 2;
	return change_value/2 * (current_frame*current_frame*current_frame*current_frame*current_frame + 2) + start_value;
}


inline float easeSinIn(float current_frame, float start_value, float end_frame, float change_value)
{
	return   -change_value * cosf(current_frame/end_frame * (Pi/2)) + change_value + start_value;
}

inline float easeSinOut(float current_frame, float start_value, float end_frame, float change_value)
{
	return   change_value * sinf(current_frame/end_frame * (Pi/2)) + start_value;
}

inline float easeSinInOut(float current_frame, float start_value, float end_frame, float change_value)
{
	return -change_value/2 * (cosf(Pi*current_frame/end_frame) - 1) + start_value;
}

inline float easeExponentialIn(float current_frame, float start_value, float end_frame, float change_value)
{
	return change_value * powf( 2, 10 * (current_frame/end_frame - 1) ) + start_value;
}

inline float easeExponentialOut(float current_frame, float start_value, float end_frame, float change_value)
{
	return change_value * ( -powf( 2, -10 * current_frame/end_frame ) + 1 ) + start_value;
}

inline float easeExponentialInOut(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame/2;
	if (current_frame < 1)
		return change_value/2 * powf( 2, 10 * (current_frame - 1) ) + start_value;
	current_frame --;
	return change_value/2 * ( -powf( 2, -10 * current_frame) + 2 ) + start_value;
}

inline float easeCircularIn(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame;
	return -change_value * (sqrtf(1 - current_frame*current_frame) - 1) + start_value;
}

inline float easeCircularOut(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame;
	current_frame--;
	return change_value * sqrtf(1 - current_frame*current_frame) + start_value;
}

inline float easeCircularInOut(float current_frame, float start_value, float end_frame, float change_value)
{
	current_frame /= end_frame/2;
	if (current_frame < 1)
		return -change_value/2 * (sqrtf(1 - current_frame*current_frame) - 1) + start_value;
	current_frame -= 2;
	return change_value/2 * (sqrtf(1 - current_frame*current_frame) + 1) + start_value;
}

2. Example App

Test each codes.

<Easing Tester>