> ..since at least Eagle ver 5 if not earlier.
>> Did you know that the produced Gerbers in cases DO NOT reflect what
>> you see on the screen?
>>
>> Now, someone pointed out that Gerbers are vector.
>> True,but that has noting to do with fonts or anything else except the
>> Gerber strokes as a collection, are supposed to represent the original:
>> a PCB pad, a logo scribble, Cyrilic font, Arabic font, or any other font
>> AS CREATED AND SEEN ON THE SCREEN.
>>
>> MOST irritating is that any text in proportional font on the screen
>> is rendered as their vector font.
>>
>> Next, that the (vector font) characters look stunted; most especially
>> the "R" looks as if its legs were sawed off.
>> The screen version is elegant; you will NOT get what you see.
>>
>> Also, some of the vector font symbols are totally trashed, for
>> there is no replacement unless one wishes to construct one using a
>> circle and (at least on the screen) a "R"; result has the inelegant and
>> trashy looking vector font "R".
>>
>> Such junk is not seen unless one uses an independent Gerber viewer.
>> **
>>
>> Now, on occasion, a layer may "inherit" AND/OR "ghost" something from
>> another layer, and move the position as well.
>> In one particular case, (so to speak) without asking, a text got
>> solder-masked (the "ghost" because i never saw it since i do not bother
>> turning that layer on). And that solder mask was (o be polite)
>> mis-positioned.
>> At the same time, a placed circle (layer 1 Top, made for no hole in
>> center) got duplicated in layer 30 Bstop and position was changed (here
>> is the "ghosting").
>> Furthermore, that layer 1 circle got duplicated in layer 290 Tstop
>> and the position was ALSO changed.
>> The result was a total mess
>> **
>> SO, VERY carefully review ALL layers on the screen at minimum and fix
>> as needed.
>> Use a Gerber viewer to double-check the results, especially fonts.
>>
>> Naturally, because a rich owner of Eagle has decided to also be
>> greedy, expect these problems WILL NEVER be fixed.
> Well, I just discovered yet another condition where you do NOT get what you see on the screen.
> Try printing to a PDF; text with NO regard to (source/screen) font will be severely altered.
> Seems there may be NO work-around, so documentation may be curtailed...
>
>
I've been writing a gerber parser lately and thus researched the topic a bit. There's a line type that eagle and ossibly other tools produce that's not in ucamcos standard. namely line type 22. there are some in the gerbv testcases (am-test.gbr). There may also be some bugs in some renderers with respect to overlapping primitives ending up wrong. You might need a veryfing Gerber parser or sthg...