Tip: distortion when drawing markers on a sphere

tip-draw-ellipse-instead-spheres-as-marker.pde

/*
When you want to draw markers on a sphere keep in mind that 3D markers (like spheres and boxes) are distorted because you see their top as well as their sides instead of just their top.
*/

perspective(atan(r/distToCam)*2, wdh, distToCam, 10000);  //fov=35deg    //atan(hd2/distToCam)*2
camera(0, 0, -distToCam, 0, 0, 0, 0, 1, 0);
scale(-1, 1, 1);

background(0);

pushMatrix();
rotateX(HALF_PI);
noFill();
stroke(128);
hint(ENABLE_DEPTH_TEST);
sphere(r * globeScaler);
hint(DISABLE_DEPTH_TEST);
popMatrix();

fill(255); //, 0, 0);
noStroke();
for (float a=-HALF_PI; a<=HALF_PI; a+=PI/30) {
  pushMatrix();
  rotateY(a);
  translate(0, 0, r * globeScaler);
  ellipse(0,0,40,40);
  popMatrix();

  pushMatrix();
  rotateX(a);
  translate(0, 0, r * globeScaler);
  ellipse(0,0,40,40);
  popMatrix();
}

unwanted:

desired: