     discard;
   }
 
+  angle = atan(texture2D(hmap, gl_TexCoord[0].st + vec2(0.01f,0.0f)).r*65536
+               - high, 0.01f * screen_size.x);
+  alpha += 0.125f - angle / (3.14159f * 8.0f);
+
   if (rel + value*5 > 3.5)
     gl_FragColor.rgb = value * gl_SecondaryColor.rgb;
   else

    if (rel * gl_Color.a + (1.0f-rel) * gl_SecondaryColor.a > 0.25f)
      discard;

    alpha = 0.25f;
  } else if (screen_coords.y > low && screen_coords.y <= low + mixing) {
    if ((value-0.5f)*4.0f < (screen_coords.y - low)/mixing)
      discard;

  float value;
  float thickness;
  float mixing;
  float alpha = 0.50f;
  float angle;

  if (gl_TexCoord[0].t > 1)
    thickness = line_thickness;
