# Solving constraints/joints in 1D

For n points moving in 1 dimension.

Position and velocity are known for each point.

Each frame a basic integration is done for each point:

velocity += forces * timestep;
forces = 0;
position += velocity * timestep;


Each point (except for the first one) is attached to the point following it (e.g to its right) with a distance joint of the form

point2 - point1 < distance
&&
point2 - point1 > 0


Which means that the points shouldn't be further appart than distance or closer than 0.

Energy should be conserved, i.e a point should be able to push/pull another.

I tried to solve every constraints with impulses, but it messes with velocities. (at least the way I did it..)

Searching around, I found a lot of resources but I'm unfortunately not able to understand all of it.

If anyone can give me a general idea / starting point ?