fine drawing is aliased, how to fix it?

[florinandrei]

I've just started to learn PS.

I am trying to draw a light mask for a tachometer (a device that measures rotation speed). Size is whatever fits on a Letter size trasparent foil. It should look kind of like this, but with far more segments (ideally around 2000):

So I've tried to increase the number of segments, and then display the result in gv, but the segments look jagged:

What can I do to draw and display those segments smooth? The PS file is listed at the end.

r2 is the outer radius of the diagram.

len is the length of a segment

u is the scale factor.

count is the number of segments.

Basically, I blow everything up a lot, hoping to get rid of aliasing artifacts. But that doesn't help.

%!PS

/r2 2500000 def

/len r2 10 div def

/u 0.0001 def

/count 1000 def

/ainc 360 count div def

/w 1 u div def

300 400 translate

/r1 r2 len sub def

u u scale

0.5 u div setlinewidth

0 ainc 360 {

        /angle exch def

        /sine angle sin def

        /cosine angle cos def

        /x1 r1 cosine mul def

        /y1 r1 sine mul def

        /x2 r2 cosine mul def

        /y2 r2 sine mul def

        newpath x1 y1 moveto x2 y2 lineto stroke

} for

showpage

[Test Screen Name]

What you are seeing is entirely normal. As defined, a black and white line will be rendered in pixels of black and white only, and will have pixel-sized steps.

Antialiasing isn't part of the PostScript language. Many PostScript interpreters will not do this at all, others may have it as an option, but you need to refer to the product documentation.