Story about a two dimensional being's quest to discover the third dimension

Question

Please note that this is not the Flatland story, but it may have referenced it.

I recall reading a different story about a programmer writing a virtual two dimensional world simulation, which then starts glitching because it manages to synchronize with an actual living two dimensional being.

The story then relates the account of that being and his life fishing, and living in underground houses through a series of conversations or descriptions between the human and the throg(?) / throc(?)

Eventually the two dimensional being meets a sage from their world who teaches them how to perceive the third dimension, and he leaves his world, at which point the connection to the humans computer program is severed.

The human tries to run the simulation again, but in vain, as it just behaves normally and never glitches again.

This story was probably in the 80's? Though it may have been published earlier.

Answer 1

This might be A.K. Dewdney's The Planiverse

In the spirit of Edwin Abbott Abbott's Flatland, Dewdney and his computer science students simulate a two-dimensional world with a complex ecosystem. To their surprise, they find their artificial 2D universe has somehow accidentally become a means of communication with an actual 2D world – Arde. They make a sort of "telepathic" contact with "YNDRD," referred to by the students as Yendred, a highly philosophical Ardean, as he begins a journey across the western half, Punizla, of the single continent Ajem Kollosh to learn more about the spiritual beliefs of the people of the East, Vanizla. Yendred mistakes Dewdney's class for 'spirits' and takes great interest in communicating with them. The students and narrator communicate with Yendred by typing on the keyboard; Yendred's answers appear on the computer's printout. The name Yendred (or "Yendwed", as pronounced by one of the students, who has a speech impediment) is simply "Dewdney" reversed.

Written as a travelogue, Yendred's journey through the West takes him through several cities. He visits the Punizlan Institute for Technology and Science, where Arde's technology is explored in great detail. For example, all houses are underground, so as not to be demolished by the periodic 2D rivers; nails are useless for attaching two objects, so tape and glue are used instead; most Ardean creatures cannot have deuterostomic digestive tracts since they would split into two; even games such as Go have one-dimensional Alak analogues. An appendix explains various other aspects of two-dimensional science and technology which could not fit into the main story.

The underlying allegory culminates in Yendred's arrival at the watershed of the continent and the planet's only building above ground, where he at last finds Drabk, an Ardean who professes 'knowledge of the Beyond,' and teaches Yendred to fly. Yendred finds that to keep contact with Earth is no longer of benefit, and contact with Arde is lost.

Recognizing that this sounded a lot like the classic novel, Flatland, other than the computer simulation aspect, I searched for computer simulation flatland and it was the second result.