typography - Is there a way to create gradations between two given weights of a particular font?

Was doing some reading and came across this which I found very insightful:

Weight

This is the difference between bold typefaces or versions of a typeface, and regular typefaces or versions of a typeface, as shown here by the difference between Arial Black and Arial.

As with many of the features to be discussed below, this is not a binary but a gradual contrast -- there is, at least in principle, a continuum of boldness, even if technologies like the word processor reduce it to a binary choice.

-Theo van Leeuwen

It is true that computers reduce it to a binary choice. So is there a way to expand the number of iterations any given font has within those binary choices? I'm imagining selecting my text and then using my scroll-wheel not for font size but for font thickness, being able to stop not on 2 or 3 or 9 thicknesses but limitless thicknesses for a given font.

Does anyone know of any studies or conceptual graphic design projects that have looked at this?

Answer

Technically it is possible to interpolate an existing font.

Image 1: Interpolation of letter K of Arial regular to 2.2 times Arial black.

Quite many fonts lend to simple interpolation Arial was chosen for simplicity, and clarity of explaining the interpolation. In this case the vertex numberings were a bit out of sync so i had to identify the first corner again. What I basically did is the same thing as MM font does.

Explanation of how it works:

This is how it works. For each vertex and Bezier tangent handle point. Identify counterpart in different weight, find the vector between the point.

Image 1: Vectors between corresponding points.

You can then add the original point vector plus offset vector times a number between 0-100% to get something between these font weights. It is also possible to go further than the target giving you over interpolation. Animators call the same technology morphs or blend shapes. Not all fonts lend themselves to be worked with to this technology.

One can also be more complex you can make things out of interpolated pieces and then do other constraint based tools such as rounds after merge etc. So if one does this you can make fonts that are interpolated but once flattened nobody else can interpolate them. Same happens if you do manual teaks by inserting points etc.

Current generation of fonts are actually very poor at doing this. Old postscript user fonts could have done nearly any kind of custom building conceivable so fonts were in this regard better years ago. One reason to use EPS files for custom font programs that can then be converted to conventional fonts.