Zhichu Chen wrote:

Fine, I made it in a very weird way. I constructed a very strange path to go through the outer path in counter- clockwise direction and inner path in clockwise dir- ection and filled it. I don't feel good but it can be done now.

Currently, that is how it should be done. Maybe a future version of metapost will be able to handle this natively. Best wishes, Taco

Zhichu Chen wrote:

Cool, but just curiosity, metapost can handle fonts right? How those glyphs don't have this problem? I've read the specification of the type1 fonts, they don't seem to have such weird paths, just some borderlines with different directions.

PostScript paths are more advanced than Metapost's draw objects, but Metapost never sees these paths of font glyphs at all. (well, except via the new primitive 'glyph X of', but that indeed does have this problem.) Best wishes, Taco

I assume there's no "--" between "reverse" and "fullcircle scaled 1cm" :) Well, my example is too simple. Actually, I was trying to draw a treble clef, and when there're too many intersection points (caused by the -- operator to join every path together) the output is not so good, kind of like an even-odd-fill. Anyway, I wrote a macro trying to handle it, but it's still weird for me. =================================================== def getridof(expr mypath) = save p, q, r, l, Oringin, Mode , MagicPoint ; pair Oringin ; Oringin := center mypath ; pair MagicPoint ; numeric Mode ; Mode := 0 ; path p[], q[], l ; q0 := mypath ; q1 := llcorner currentpicture -- lrcorner currentpicture ; q2 := lrcorner currentpicture -- urcorner currentpicture ; q3 := urcorner currentpicture -- ulcorner currentpicture ; q4 := ulcorner currentpicture -- llcorner currentpicture ; for i=1 upto 4 : q[i+4] := q[i] ; endfor q11 := llcorner currentpicture -- Oringin ; q12 := lrcorner currentpicture -- Oringin ; q13 := urcorner currentpicture -- Oringin ; q14 := ulcorner currentpicture -- Oringin ; for i=1 upto 4 : p[i] := q[i] for j=1 upto 3 : -- q[i+j] endfor ; endfor if (((llcorner currentpicture -- Oringin) intersectiontimes mypath) = (-1,-1)) : if (((lrcorner currentpicture -- Oringin) intersectiontimes mypath) = (-1,-1)) : if (((urcorner currentpicture -- Oringin) intersectiontimes mypath) = (-1,-1)) : Mode := 4 ; else : Mode := 3 ; fi else : Mode := 2 ; fi else : Mode := 1 ; fi l = q[10+Mode] cutafter mypath ; MagicPoint = point length(l) of l ; p0 := p[Mode]--l--(q0 cutbefore MagicPoint)--(q0 cutafter MagicPoint)--(reverse l)--cycle ; clip currentpicture to p0 ; draw p0 withcolor cyan ; enddef ; =================================================== If I use =================================================== path p[] ; p1 = fullcircle scaled 10 cm ; p2 = reverse fullcircle scaled 1cm shifted (2cm,2cm) ; p3 = reverse fullcircle scaled 1.5cm shifted (2cm,-2cm) ; p4 = reverse fullcircle scaled 1.75cm shifted (-2cm,2cm) ; fill p1 ; getridof(p2) ; getridof(p3) ; getridof(p4) ; =================================================== then only p2 was cut off, you can change the order and only the first path can be handled. If I use pa[] as the path variables rather than p[], that would be fine. I don't know why, I mean I've used the "save" operator. On Wed, Jun 24, 2009 at 4:21 PM, Wolfgang Schuster wrote:

fill fullcircle scaled 2cm -- reverse -- fullcircle scaled 1cm -- cycle ;

Wolfgang

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-- Best Regards Chen ---------------------------------------------------------------- Zhi-chu Chen | Shanghai Synchrotron Radiation Facility No. 2019 | Jialuo Rd. | Jiading | Shanghai | P.R. China tel: 086 21 5955 3405 | zhichu.chen.googlepages.com | www.sinap.ac.cn ----------------------------------------------------------------

Zhichu Chen wrote:

I guess I should use as few variables as possible, I suppose no one would name their paths "Helper" ;)

Helper sounds ok, but ...

pair Oringin ; Oringin := center p ;

... Oringin kind of funny

Helper1 := llcorner currentpicture -- lrcorner currentpicture ;

shorter: Helper1 := leftboundary currentpicture ; ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------

In article <769ba7780906240342s4939ac2foe7bfd783ad2e82ee@mail.gmail.com>, Zhichu Chen wrote:

Well, my example is too simple. Actually, I was trying to draw a treble clef

If your goal is to draw a path with pens of varying width (kind of calligraphic strokes),'penpos' and 'penstroke' may be your friends (defined in plain.mp). This is what I've come out with by about 15 minutes of trial and error (disclaimer: this is my first attempt at using these macros beyond trying to draw a sans-serif 'l' - I'm not a designer at all): fill unitsquare scaled 12cm shifted (-6cm,-6cm) withcolor .625red; b = 2pt; % Default pen width w = 30mm; % Width of treble clef h = 100mm; % Height of treble clef % Specify breadth and angle of pen at keypoints: penpos 1 (0.5b, 30); penpos 1.5 (b, 15); penpos 2 (3b, 0); penpos 3 (5b, -90); penpos 4 (3b, -180); penpos 5 (b, 90); penpos 6 (5b,0); penpos 6.5 (4b, -30); penpos 7 (.5b, 0); penpos 8 (5b, 90); penpos 9 (3b, -180); penpos 10 (b, -180); % Fix x coords of keypoints x1=0; x1.5=1/2[x1,x2]; x5=x1=x3=x8; x10=1/2[x9,x1]; x7=1/2[x3,x4]; x4-x6=w; x1=1/2[x2,x4]; x3-x2=x2-x6; x9=1/2[x1,x2]; x6.5=1/2[x5,x6]; % Fix y coords of keypoints y1=0; y1.5=y1; y6=y2=y4=1/2[y3,y1]; y3-y1=y1-y5=1/10h; y5-y10=2(y3-y1); y8-y7=y3-y1; y9=y7; y8-y3=y3-y10; y6.5=1/2[y6,y7]; drawoptions (withcolor background); % Draw (an incomplete and ugly) treble clef penstroke z1e .. z1.5e .. z2e .. z3e .. z4e .. z5e .. z6e .. z6.5e .. z7e .. z8e .. z9e .. z10e; drawoptions(withcolor black); labels.lft(1,1.5,2,3,4,5,6,6.5,7,8,9,10); You must take special care never to cross the left and right edges of the pen. See The METAFONTbook for details and examples. Regards, Nicola

Hi Zichu, an other approach (mkiv + lilypond font): \definefont[music][name:emmentaler20 at 72pt] \starttext \music\char57770 \stoptext :-) Greetings Lutz 2009/6/24 Zhichu Chen

Hi Nicola,

Thank you very much for your example and the idea. It's amazing, I thought it's just a metafont thing and metapost just can't do that.

Thank you for your information again.

On Wed, Jun 24, 2009 at 10:12 PM, Nicola wrote:

...

In article <769ba7780906240342s4939ac2foe7bfd783ad2e82ee@mail.gmail.com>, Zhichu Chen wrote:

...

Well, my example is too simple. Actually, I was trying to draw a treble clef

If your goal is to draw a path with pens of varying width (kind of calligraphic strokes),'penpos' and 'penstroke' may be your friends (defined in plain.mp). This is what I've come out with by about 15 minutes of trial and error (disclaimer: this is my first attempt at using these macros beyond trying to draw a sans-serif 'l' - I'm not a designer at all):

fill unitsquare scaled 12cm shifted (-6cm,-6cm) withcolor .625red; b = 2pt; % Default pen width w = 30mm; % Width of treble clef h = 100mm; % Height of treble clef % Specify breadth and angle of pen at keypoints: penpos 1 (0.5b, 30); penpos 1.5 (b, 15); penpos 2 (3b, 0); penpos 3 (5b, -90); penpos 4 (3b, -180); penpos 5 (b, 90); penpos 6 (5b,0); penpos 6.5 (4b, -30); penpos 7 (.5b, 0); penpos 8 (5b, 90); penpos 9 (3b, -180); penpos 10 (b, -180); % Fix x coords of keypoints x1=0; x1.5=1/2[x1,x2]; x5=x1=x3=x8; x10=1/2[x9,x1]; x7=1/2[x3,x4]; x4-x6=w; x1=1/2[x2,x4]; x3-x2=x2-x6; x9=1/2[x1,x2]; x6.5=1/2[x5,x6]; % Fix y coords of keypoints y1=0; y1.5=y1; y6=y2=y4=1/2[y3,y1]; y3-y1=y1-y5=1/10h; y5-y10=2(y3-y1); y8-y7=y3-y1; y9=y7; y8-y3=y3-y10; y6.5=1/2[y6,y7];

drawoptions (withcolor background); % Draw (an incomplete and ugly) treble clef penstroke z1e .. z1.5e .. z2e .. z3e .. z4e .. z5e .. z6e .. z6.5e .. z7e .. z8e .. z9e .. z10e; drawoptions(withcolor black); labels.lft(1,1.5,2,3,4,5,6,6.5,7,8,9,10);

You must take special care never to cross the left and right edges of the pen. See The METAFONTbook for details and examples.

Regards, Nicola

...

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...

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___________________________________________________________________________________

...

-- Best Regards Chen ----------------------------------------------------------------

Zhi-chu Chen | Shanghai Synchrotron Radiation Facility No. 2019 | Jialuo Rd. | Jiading | Shanghai | P.R. China tel: 086 21 5955 3405 | zhichu.chen.googlepages.com | www.sinap.ac.cn ----------------------------------------------------------------

___________________________________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : https://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net

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