图形处理中一个比较有用的函数

// Template minimum
template <class T>
T min(T a, T b)
{
  return (a<b)?a:b;
}

// Maximum
template <class T>
T max(T a, T b)
{
  return (a>b)?a:b;
}

// Linear interpolation 线性插值
template <class T>
T lerp(T a, T b, float bal)
{
  bal = clamp<float>(bal, 0, 1);
  return a + (b - a) * bal;
}

// Floating-point absolute using some binary tricks
float absf(float x)
{
  *(long *)&x &= 0x7fffffff;
  return x;
}

// Makes an int "wrap" to fit in the range 0..255
int wrap(int x)
{
  return (x%256);
}