   Smooth shading concave polygons
  Hello,I am making a concave polygon by dividing it into different quads. With flat shading, everything is fine, but with smooth shading, each quad is shaded differently (as it should be). I want that the whole concave polygon be smooth shaded as one unit and not individual quads.Is there any other method of drawing smooth shaded concave polygons in OpenGL?Top to bottom shading is easy when there is only one row of quads - upper two vertices can be given one color and lower two the second color. How to perform left to right shading in this case i.e. how to interpolate starting and ending colors across the quad-row for smooth shading?Thanks for the helpRohit[Edited by - rohitK on May 6, 2009 10:56:43 PM]