Eventually one color will completely take over the screen. Which one is completely random. Sometimes it can be done in 5 minutes, sometimes it takes hours.
This program exists for UNIX (using MIT SHM extension of the X server) and for Win32 (using Direct Draw).

Initialization, the blues are going down, the reds are coming up.

Collision! They will mostly stop each other now.

Equilibrium. They will struggle a lot here to break through each others
defenses.

Red breaks through!

Because red has weakened its defense by leaking through, it gives blue a
chance to break through.

Smaller collision, more breakthrough.
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