I am in awe at this. Thanks for sharing.

On Wed, 19 Jul 2023 at 18:11, Henning Hraban Ramm <texml@fiee.net> wrote:
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.

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

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