PCSx ReARMed: What exactly are "Interlacing modes"?

Hi everybody.

When emulating the PS1 with the PCSx ReARMed core, I noticed that there is an Option in “Quick Menu => Options” with the description “Enable Interlacing Modes”. This is by default set to “off”.

Can someone explain to me, what this option is for?

As far as I know, “Interlace” means that the vertical resolution is apparently doubled by showing the odd and even lines of a picture alternately. But I’m not really sure.

That said, I have the following considerations:

  • Am I missing something when I leave it in the “off” setting?
  • Are there games that do not work properly with the interlace-setting on “off”?
  • How can I know when to turn this option on?

I would be glad if someone could explain this Interlacing thing to me.