For a very detailed discussion of font rendering from the historical compromises that caused sever line length problems, and how to properly render with reliabl

For a very detailed discussion of font rendering from the historical compromises that caused sever line length problems, and how to properly render with reliable sizes at at any display ppi, I recommend reading this[1] paper by Maxim Shemanarev and the AGG project. A key reason we have font size problems today was Microlsoft's decision aggressively hint their display fonts. The hinting was so strong, many glyphs had their horizontal position forcibly quantized on the pixel grid. Thus 1% changes in font size might round to different pixels, with unpredictably and error accumulating into huge differences in length for each line. Scaling font size could make dialog unusable, so a lot of software used fixed px sizes so the GUI was predictable. Microsoft finally addressed this problem in recent versions of Windows, but it will take time to undo the "Only 96 ppi exists" damage. Font rendering is complicated! [1] http://www.antigrain.com/research/font_rasterization/index.html http://www.antigrain.com/research/font_rasterization/index.h...