public class PolygonRenderer extends AbstractRenderer
{
   //Number of points or vertices we want to use
   private final static int VERTS = 4;

   //A raw native buffer to hold the point coordinates
   private FloatBuffer mFVertexBuffer;

   //A raw native buffer to hold indices
   //allowing a reuse of points.
   private ShortBuffer mIndexBuffer;
   private int numOfIndices = 0;
   private long prevtime = SystemClock.uptimeMillis();
   private int sides = 3;

   public PolygonRenderer(Context context)
   {
      //EvenPolygon t = new EvenPolygon(0,0,0,1,3);
      //EvenPolygon t = new EvenPolygon(0,0,0,1,4);
      prepareBuffers(sides);
   }
   private void prepareBuffers(int sides)
   {
      RegularPolygon t = new RegularPolygon(0,0,0,1,sides);
      //RegularPolygon t = new RegularPolygon(1,1,0,1,sides);
      this.mFVertexBuffer = t.getVertexBuffer();
      this.mIndexBuffer = t.getIndexBuffer();
      this.numOfIndices = t.getNumberOfIndices();
      this.mFVertexBuffer.position(0);
      this.mIndexBuffer.position(0);
   }
   //overriden method
   protected void draw(GL10 gl)
   {
      long curtime = SystemClock.uptimeMillis();
      if ((curtime - prevtime) > 2000)
      {
         prevtime = curtime;
         sides += 1;
         if (sides > 20)
         {
            sides = 3;
         }
         this.prepareBuffers(sides);
      }
      //EvenPolygon.test();
      gl.glColor4f(1.0f, 0, 0, 0.5f);
      gl.glVertexPointer(3, GL10.GL_FLOAT, 0, mFVertexBuffer);
      gl.glDrawElements(GL10.GL_TRIANGLES, this.numOfIndices,
      GL10.GL_UNSIGNED_SHORT, mIndexBuffer);
   }
}