Function DampedString

examples/FirstScene/main.cpp:409–440

}

Nz::Vector3f DampedString(const Nz::Vector3f& currentPos, const Nz::Vector3f& targetPos, float frametime, float springStrength)
{
	// Je ne suis pas l'auteur de cette fonction
	// Je l'ai reprise du programme "Floaty Camera Example" et adaptée au C++
	// Trouvé ici: http://nccastaff.bournemouth.ac.uk/jmacey/RobTheBloke/www/opengl_programming.html#4
	// Tout le mérite revient à l'auteur (Qui me permettra ainsi d'améliorer les démos, voire même le moteur)

	// calculate the displacement between the target and the current position
	Nz::Vector3f displacement = targetPos - currentPos;

	// whats the distance between them?
	float displacementLength = displacement.GetLength();

	// Stops small position fluctuations (integration errors probably - since only using euler)
	if (Nz::NumberEquals(displacementLength, 0.f))
		return currentPos;

	float invDisplacementLength = 1.f / displacementLength;

	const float dampConstant = 0.000065f; // Something v.small to offset 1/ displacement length

	// the strength of the spring increases the further away the camera is from the target.
	float springMagitude = springStrength*displacementLength + dampConstant*invDisplacementLength;

	// Normalise the displacement and scale by the spring magnitude
	// and the amount of time passed
	float scalar = std::min(invDisplacementLength * springMagitude * frametime, 1.f);
	displacement *= scalar;

	// move the camera a bit towards the target
	return currentPos + displacement;
}