I'd like to have text where the proportions of glyph widths continuously change. One extreme would be that all glyphs would have the same width, and the other extreme would be that glyphs usually narrow would be significantly narrower than glyphs usually wide (“i” would be significantly narrower than “M” for example).
I know that variable OTF fonts exist and there could be a font with variable width proportions, but I didn't find such font. An other idea is to calculate the widths of the particular glyphs used in the text at the particular positions and adjust the glyph for each position manually, but it would be a lot of work and a lot could go wrong because I don't have experience with editing fonts. The third idea is to use a program for morphing images to generate shapes between the monospaced variant of a glyph and the proportional variant of a glyph, but there could arise ugly shapes and areas with grey color.
What is the best way to vary the glyphs in this way? If you know a font with variable width proportions, a program that can morph vector images well, or you have any other idea of how to do it, please, let me know about it.