title: Matlab calculate reflection of Vector
body: <p>I have to calculate the Specular Highlights (phong) of an Image. the normal Vector and the "light vector" are given. Now I have to calculate the light reflection - is there an efficient matlab function to flip the light Vector over the normal vector to get the reflected-light-vector?</p>
  
  <p>I<sub>spec</sub> = k<sub>s</sub> * I * (r * v)<sup>p</sup></p>
  
  <p>Where:
  <code>l</code> is the light vector<br>
  <code>n</code> is the normal vector of surface<br>
  <code>r</code> is the reflection vector<br>
  <code>v</code> is the vector from reflection point to viewer<br>
  <code>p</code> is the shininess<br></p>