title: OpenGL : drawing line using degenerate triangle
body: <p>In my engine, I want to avoid having line, and separate triangle types. I want to draw the lines using a triangle where 2 verts are identical. But in opengl, this triangle wont be displayed because it has zero area, and therefore can't cover a pixel.</p>
  
  <p>Internally, at the driver level, an opengl line is drawn using a degenerate triangle, and a different rasterization rule is used where it draws at least one pixel per scanline.</p>
  
  <p>D3d had some option where you could set the rasterization to always draw the first pixel per scan line--effectively accomplishing what I want in d3d.</p>
  
  <p>But how can I do this with opengl? I don't see any command that would allow you to change the rasterization rules. </p>