What problems can arise with TrueType hinting? This is how FreeType’s auto-hinter works see below for more. No hints in the font are used or needed instead, the rasterizer scans and analyzes the glyphs to apply corrections by itself. The hinting logic is completely in the rasterizer. The hinting logic is in the font ideally, all rasterizers simply process these instructions to get the same result on all platforms. The font contains exact instructions (also called bytecode) on how to move the points of its outlines, depending on the resolution of the output device, and which intentionally distort the (outline) shape to produce a well-rasterized result. This is how PostScript Type 1 and CFF hints work. More sophisticated rasterizers are able to produce better rendering results. The hinting logic is partly in the font and partly in the rasterizer.
The font contains hints (in the original sense of this word) to guide the rasterizer, telling it which shapes of the glyphs need special consideration. In general, there are three possible ways to hint a glyph. It can be accompanied by antialiasing and (on liquid crystal displays) subpixel rendering for further clarity.įor optimal results, a font instructor should follow these guidelines:Īt small sizes, chance effects should not be allowed to magnify small differences in the original outline design of a glyph.Īt large sizes, the subtlety of the original design should emerge. At low screen resolutions, hinting is critical for producing a clear, legible text. What exactly are hints?įont hinting (also known as instructing) is the use of mathematical instructions to adjust the display of an outline font so that it lines up with a rasterized grid. The library has a central API function, TTF_autohint, which is described below.īundled with the library there are two front-end programs, ttfautohint and ttfautohintGUI, being a command line program and an application with a Graphics User Interface (GUI), respectively. The idea is to provide the excellent quality of the auto-hinter on platforms that don’t use FreeType. Ttfautohint is a library written in C that takes a TrueType font as the input, removes its bytecode instructions (if any), and returns a new font where all glyphs are bytecode hinted using the information given by FreeType’s auto-hinting module. Ttfautohint Werner Lemberg Version 1.8.4 Introduction
0 kommentar(er)
