Does using this hint()
solve it?
void setup() {
size(600, 600, P3D);
}
void draw() {
background(#123456);
fill(255);
sphere(300);
textSize(100);
hint(DISABLE_DEPTH_TEST);
// everything you want on top goes here
fill(0);
text("abcdefgh", 50, 150);
hint(ENABLE_DEPTH_TEST);
}