"xtideclock" is a desktop clock for X window system. It shows the current time, tidal hight and sun/moon's raise/set time.
As shown in below figure, there are tree hands on the clock. White hands are showing current hour and minute, and red one is a 24-hour hand.
A blue ellipse shows today's tide condision and a circle shows average sea level. When the edge of the ellipse are out of the circle that shows sea is being flood,and inside shows ebb tide. Therefore, when you look at the edge of ellipse under the red hand you can know current sea level. Divisions that can see 3, 6 and 9 oclock positions show 50cm or 1m, 2m, 4m (depend on defined position).
Band of outside (lavender color) shows today's sun rising time, and inside (gray) shows today's moon rising time.
Before running it you have to make a ~/.tiderc to define a position where you want to watch conditions. The format of the .tiderc file is TD2. I think TD2 format is local format only in Japan.
Therefore, I try to make TD2 files from XTide's data, and put here. I'm not shure it works well because there are too many defined position. Get and move to ~/.tiderc might be work.
Thre are some options on the xtideclok.
Here is a source. Thre are many JAPANESE comment on the source because I'm not good on English (As you know by reading this page). But I think you can compile it.
Please do not use an navigation. The tidal calculating engine is made by "KATUODORI"/"Storm Petrel" (handle on the computer online services), not me. So I think Tide21Lib.h/c++ are not a GPL licence (but free).