User:Wierd W

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Scary creator of the seemingly vaporware Greenville font (A reasonable facsimilie of MS Tahoma). Looks disturbingly like jesus, and can be a total pain in the posterior at times. Spends countless hours working on said font, allbeit with sometimes large lapses in attention to said duties.

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Currently at a bit of an impass that ReactOS + Freetype (Some combination of the two) Has difficulties rendering Greenville properly; Possibly due to Software Patent issues concerning hint instructions-- Attempts to alleviate the problem with integrated SBITs (Software Bitmaps that over-ride the glyph rendering engine) have been less than successful, as ROS outputs unintelligable garbage, instead of recognisable glyphs when SBITs are present.

Despite this problem, work continues on a windows only environment. So far so good....

Wish me luck.


Update: As of a few months ago, ReactOS is able to display SBIT data. I have also tracked down much of the problem with improper rendering to be FreeType's fault. Here is the nitty-gritty details:

The windows rasterizer uses ONLY 16 shades of grey. While the Freetype rasterizer overzealously uses 256 shades of grey. This causes lots of problems...

Pixel values are determined by an "area covered" algorithm. Each "pixel" is divided into 256 subunits. These subunits are deemed to be "covered" if the outline crosses over them. Since freetype uses the full density of this space to determine the pixel value, there is essentially NO tolerance for error in placing of hint instructions. That is to say, in order to get "Pure white", you must cover 0 of 256 sub units for that pixel... Unfortunately, the same is true for "Pure black"-- 256 of 256 subunits must be covered to get pure black for that pixel. This makes the overwhelming majority of pixels at small point sizes turn out some mottled shade of grey; and also renders clean glyph edges IMPOSSIBLE with diagonal lines.

If you compare this to the windows rasterizer, which has a higher granularity, you suddenly find there is this magical thing called "tolerance." As long as less than 16 subunits are covered, the pixel will render as "Pure white", and if more than 240 subunits are covered, it will render as "pure black". This tolerance applies to shades of grey in between as well, producing more uniform areas around glyph edges.

Since about 99.99999% of TTF fonts out there EXPECT the windows rasterizer, The "freetype way" makes no sense at all. Why they did it that way is totally beyond me.