So, from what I can gather, the "pictures" are skin to portals in many other games. However they don't have a barrier, allowing geometry to intersect with existing geometry and over write it.

What astounds me more is that they included a rewind function and a freaking camera to make a portal out of anything you see.

Kinda reminds me a little bit of this one puzzle game I'd played called Antichamber. It also reminds me of the video I'd watched of Markiplier playing through Superliminal, or at least the tech demo of what it would become, iirc. I love when puzzle games play around with concepts like this since they ACTUALLY make me feel smart by putting my critical problem-solving skills to work. =^.^=

Oh totally.

What astounds me is that they pull of multiple rendering and graphics styles in one level.
One is a sketched house in 3D
Hell they even mimicked Quake 1 low resolution 320X200 graphics in a limited environment that's HD resolution over the whole level..
That was phenomenal.