Wow, the die shot! It looks like an eerie caricature of then-contemporary chip designs. I have seen blocky hand layouts, and modern (presumably) auto layouts that look like bacteria cultures. But I have never seen warped and slanted blocks.
[1]: Some macbook trackpad, note the polymide/flex substrate and rounded tracks. This isn't fully any-angle like what TopoR does though https://commons.wikimedia.org/wiki/File:Apple_MacBook_Pro,_m...
It is of Russian origin and commercial software!
In old integrated circuit manufacturing processes, with large minimum dimensions, it was possible to draw arbitrary curves without problems.
Some of the software tools were limited to straight lines or even to straight lines only at certain angles, just because the limitation simplified the algorithms, but if one really wanted, it was possible to draw anything on the masks.
On modern manufacturing processes, with extremely small minimum sizes, it has become more and more difficult to predict which will be the differences in geometry between what you draw on the mask and what will be made on the surface of the semiconductor wafer, after photolithography and etching of the layer that must be patterned.
In order to make the photolithography and etching processes more predictable, the design rules have become more and more restrictive, e.g. by allowing only vertical, horizontal and 45 degree straight lines, or only vertical and horizontal lines, or even on some layers only traces parallel to a certain direction.
Moreover there are a lot of extra constraints, e.g. the need to place dummy patterns around those that are useful, because the same pattern in a different neighborhood will be distorted in a different way, which could be hard to predict.