Re: [NTG-context] Metapost Animation of Sine

Hi,

Le 21 juill. 2021 à 10:08, Jeroen a écrit :

I use this small animation to enlarge a circle

\usemodule[animation] \setupinteraction[state=start] \starttext \startanimation[menu=yes,framerate=10] \dorecurse{7}{\expanded {\startframe \startMPcode path p; numeric n, u; u := 1cm; n:=\recurselevel*u; p := fullcircle scaled n; draw p; \stopMPcode \stopframe}} \stopanimation \stoptext

This I use to draw a sine

\starttext \startMPcode draw(-90/360*1.5cm,-0.9cm) for i = -90 upto 630: .. (i/360*1.5cm,0.9cm*(sind(i)))endfor; \stopMPcode \stoptext

When I put it together to animate the sine as following, it does not entirely create the sine animation I am looking for

\usemodule[animation] \setupinteraction[state=start] \starttext \startanimation[menu=yes,framerate=10] \dorecurse{7}{\expanded {\startframe \startMPcode path p; numeric n, u; u := 1cm; n:=\recurselevel*u; p := (-90/360*1.5cm,-0.9cm) for i = -90 upto 630: .. (i/360*1.5cm,0.9cm*(sind(i))) endfor shifted (n,0); draw p; \stopMPcode \stopframe}} \stopanimation \stoptext

What better way can I create a sine animation with Metapost?

Here is another way to do your animation. This is doing something, but I guess not what you want. Could you describe what do you have in mind ? \starttext \dorecurse{7}{ % 3180 \startMPpage myvariable := #1 ; path p; numeric n, u; u := 1cm; n:=myvariable*u; p := (-90/360*1.5cm,-0.9cm) for i = -90 upto 630: .. (i/360*1.5cm,0.9cm*(sind(i))) endfor shifted (n,0); draw p; \stopMPpage } \stoptext Fabrice.