title: How do I get rid of jagged edges on my model with OpenGL?
body: <p>I am using OpenGL to render 3D models, but there is a strange graphical glitch that seems to be occurring. Whenever a darker color is drawn over a lighter color, the edges are very jagged. As the camera moves, these jagged edges will expand and contract sort of like a sine wave that varies frequency with time.</p>
  
  <p>Here is an image of the effect:
  <a href="http://imgur.com/qeEruLT" rel="nofollow">http://imgur.com/qeEruLT</a></p>
  
  <p>The following is the OpenGL setup code I have used:</p>
  
  <pre><code>glEnable(GL_DEPTH_TEST)
  glEnable(GL_NORMALIZE)
  glEnable(GL_COLOR_MATERIAL) 
  glEnable(GL_BLEND)
  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)
  glDepthFunc(GL_LESS)
  glShadeModel(GL_SMOOTH)
  
  # Define tessalation object and callbacks
  self.tessellator = gluNewTess()
  gluTessCallback(self.tessellator, GLU_TESS_BEGIN, glBegin)
  gluTessCallback(self.tessellator, GLU_TESS_END, glEnd)
  gluTessCallback(self.tessellator, GLU_TESS_VERTEX, glVertex3dv)
  </code></pre>
  
  <p>Is there any good way to avoid this issue so these graphical errors don't appear? I have tried enabling/disabling certain features but none that I've tried have resulted in a fix, and I'm not sure what type of setting this would fall under (if any).</p>
  
  <p>I have also tried scaling up the image (both by 10 times and 100 times). The effect is not as noticeable but still apparent, and this is not ideal given the way the rest of the program is currently working.</p>