thanks for answering!,

firstly i didn't know that i was too ambitious , thought that this was the right thing to ask.

also, 2d works as long as i can get close to accurate data. it would at max 3 metres . the competition will in in april from ibiza to spain, so assume the winds speeds and water currents at that time.

i don't know if i need currents , maybe . i just want to start simulating my navigation algorithm and then i would add these features as i need . but at last i want to start with a good, competent simulator so that i don't have to change simulators at the middle.

realistic marine navigation scenario will be simulating water currents and winds according to the data of these from websites , so that i can have same marine conditions from the area we are competing in.

okay, i am not sure of what the crew of the sailboat does but i surely know the physics, if you want this is a code [Google](https://pastebin.com/b6t2X4Na)

i can change the directions of the sail by a motor and that's what my navigation algorithm also helps in! it will change the direction of the sail according to the winds speed and direction.drawing the sheet too tight, i haven't thought about it, i hues we can't change the tension midway.

we would have an anemometer for sensing the change in wind directions and speeds.so no problem in sensing that!

BTW thanks for your response, it helps me find my loopholes. but answering your questions , do you have the answer to my original question. which simulator should i use? 2d or 3d ? if you have resources of the simulator you mention , please add that too.

THANK YOU FOR YOUR TIME