title: OpenGL shader node editor
body: <p>I'm working on a material editor very similar to Unreal or Unity and I got a stuck. I have no idea how to implement the most important piece of code: how to translate diagrams / nodes to glsl, so I have some questions:</p>
  
  <ul>
  <li>Is the vertex shader contains a constant number of attributes? For example: position, texture coordinates, normals, tangents, bitangens, and all light information, or is it depending on what nodes I have in the material, such as a normal map node.</li>
  <li>Do I have to change only fragment shader code or vertex/fragment shader code or geometry/fragment/vertex shader code after diagram has changed?</li>
  </ul>