I want to make a small game where you drive a boat, but I am having an issue trying to find a tutorial that shows how to make a boat or objects have buoyancy with c++. I am new so I would like a simple answer please reply with an answer if you have one, please.
I don’t think there will be an easy solution when it comes to simulating buoyancy.
Here´s a thesis that provides a survey over some different methods
Yi Qian Sheng - Modifications to the simple method for buoyancy-driven flows
Also these slides might be of some help:
Randy Gaul - Rigid Bodies, Water Surface and Buoyancy and Wikipedia provides some equations as well.
If your game does not require simulate perfect realism I would rather try to stick with a simpler approache like a mass-spring-system and tweak it to look good and sufficient realistic. Besides being easier to implement this will probably also come with a much lower performance impact.
I just need to make objects float and react to the changing water nothing too fancy.
Probably it would help if you could elaborate further on what your detailed requirements are and what exactly you are referring to with “changing water”.
The most simple option probably would be to assume a static level of water. Then all you would have to do would be to set the world space height coordinate of your boat to the water level on level start (with an appropriate offset) and then never touch it again. If the water level is rising or falling just update on every frame.
If you are trying to add waves a simple approach would be to utilize some appropriate noise function that takes 2D-coordinates and time as input. Then you can apply this function to your water mesh and your boat to ensure it floats up if it is positioned on top of a wave. As a starting point you could try Perlin noise, which probably will not generate too great visual effects (probably ok for waves on a lake) but should come with an intermediate diffculty level in it´s implementation. If you are aiming on realistic ocean waves things are getting more complicated, the approaches I know of are all based on heavy math stuff, IFFT in the first place.
Then you also have to take into consideration how you would like to model the interaction of your boat(s) and the waves. For example: When one boat outruns another, should it´s stern wave affect the second? Or if two boats are passing each other how affect their stern waves each other regarding the overlay of their amplitudes.