[NTG-context] Re: enhancing MetaPost presentation progress graphics

Am 19.07.23 um 14:07 schrieb Taco Hoekwater:

First, find the actual point along the curve of the wave you want, then you can ask for the direction of the wave at that time, and its point:

Thank you!

pair itime, iangle, boatpos;

itime = (wave[3] intersectiontimes ((xpos,0)--(xpos,infinity))); iangle = direction (xpart itime) of wave[3]; boatpos = (point (xpart itime) of wave[3]) shifted (-5,0); % shift to center horizontally

There was still an error that I introduced: The boat on the first page is already way in, while on the last page it falls over the edge of the world. I fixed several other things and drew a nicer boat. Feel free to use it. Hraban