Animation Curves

gistfile1.c

// Quadratic

GLfloat QuadraticEaseOut(float t, float start, float end) {
	
	if (t < 0.0f) t = 0.0f;
	if (t > 1.0f) t = 1.0f;
	return -end * t*(t-2) + start;
}


GLfloat QuadraticEaseIn(float t, float start, float end) {
	
	if (t < 0.0f) t = 0.0f;
	if (t > 1.0f) t = 1.0f;
	return end * t * t + start;
}


GLfloat QuadraticEaseInOut(float t, float start, float end) {
	
	if (t < 0.0f) t = 0.0f;
	if (t > 1.0f) t = 1.0f;
	
	t *= 2;
	
	if (t < 1) return end/2*t*t + start;
	t --;
	return -end/2 * (t*(t-2) - 1) + start;
}


// Cubic

GLfloat CubicEaseOut(float t, float start, float end) {
	
	if (t < 0.0f) t = 0.0f;
	if (t > 1.0f) t = 1.0f;
	t--;
	return end*(t*t*t + 1) + start;
}


// Quintic

GLfloat QuinticEaseIn(float t, float start, float end) {

	if (t < 0.0f) t = 0.0f;
	if (t > 1.0f) t = 1.0f;
	return end*t*t*t*t*t + start;
};


GLfloat QuinticEaseOut(float t, float start, float end) {
	
	if (t < 0.0f) t = 0.0f;
	if (t > 1.0f) t = 1.0f;
	t--;
	return end*(t*t*t*t*t + 1) + start;
}


GLfloat QuinticEaseInOut(float t, float start, float end) {
	
	if (t < 0.0f) t = 0.0f;
	if (t > 1.0f) t = 1.0f;
	
	t *= 2;
	
	if (t < 1) return end/2*t*t*t*t*t + start;
	t -= 2;
	return end/2*(t*t*t*t*t + 2) + start;
}