Ejemplo n.º 1
0
int main(){
	const int xmax = 600;			// ウインドウサイズ
	const int ymax = 400;

	const int x_orig = xmax / 2;	// 位置(0, 0)はウインドウの中心
	const int y_orig = ymax / 2;
	const Point orig(x_orig, y_orig);

	const int r_min = -10;			// 範囲[-10:11)
	const int r_max = 11;

	const int n_points = 400;		// 範囲内で使用されるポイントの数

	const int x_scale = 30;			// 倍率
	const int y_scale = 30;

	Simple_window win(Point(100, 100), xmax, ymax, "exp");

	const int xlength = xmax - 40;	// ウインドウよりも少し小さい軸を作成する
	const int ylength = ymax - 40;

	Axis x(Axis::x, Point(20, y_orig), xlength, xlength / x_scale, "one notch == 1");
	Axis y(Axis::y, Point(x_orig, ylength + 20), ylength, ylength / y_scale, "one notch == 1");
	x.set_color(Color::red);
	y.set_color(Color::red);
	win.attach(x);
	win.attach(y);

	Function real_exp(exp, r_min, r_max, orig, 200, x_scale, y_scale);
	real_exp.set_color(Color::blue);
	win.attach(real_exp);
	win.wait_for_button();

	for(int n = 0; n < 50; ++n){
		ostringstream ss;
		ss << "exp approximation: n==" << n;
		win.set_label(ss.str());
		expN_number_of_terms = n;
		// 次の近似値を取得する
		Function e(expN, r_min, r_max, orig, 200, x_scale, y_scale);
		win.attach(e);
		win.wait_for_button();
		win.detach(e);
	}
}
Ejemplo n.º 2
0
void game_physics_engine::CParticalFakeSpring::UpdateForce( CPartical* pPartical, const real duration )
{
	if (!pPartical->HasFiniteMass())
	{
		return;
	}

	CVector3 position = pPartical->GetPosition();
	position -= *m_pAnchor;

	real gamma = 0.5f * (real_sqrt(4 * m_fSpringConstant - m_fDamping * m_fDamping));
	CVector3 c = position * (m_fDamping / (2 * gamma)) + pPartical->GetVelocity() * (1.0f / gamma);

	CVector3 target = position * real_cos(gamma * duration) + c * real_sin(gamma * duration);
	target *= real_exp(-0.5f * duration * m_fDamping);

	CVector3 accel = (target - position) * (1.0f / duration * duration) - pPartical->GetVelocity() * duration;
	pPartical->AddForce(accel * pPartical->GetMass());
}