Function blep

src/extended/PolyBLEPNode.cpp:35–40

inline T square(const T & x) { return x * x; }

inline double blep(const double t, const double dt)
{
    if (t < dt) return -square(t / dt - 1);
    else if (t > 1 - dt)  return square((t - 1) / dt + 1);
    else return 0.0;
}

inline double blamp(double t, const double dt)
{