Contacts implementation about consim HOT 1 CLOSED

This assumes all contacts are active all the time

Yes it does.

If I have switching contacts I will have to keep changing the size of the vectors/matrices used,
eg: x, intx, int2x ... etc
to implement this I will have to resize the Eigen::MatrixXd & Eigen::VectorXd at every integration step, are you aware of more efficient ways for implementing this?

I think keeping the maximum size is a bad idea because the matrix exponential is gonna be the most expensive computation. At first, I think that resizing everything when the number of contacts change is reasonable. Later on, if we feel like improving the code, we could pre-allocate variables for the most common numbers of contacts (e.g., 1, 2, 3 and 4), and use the correct variables depending on the current number of contacts (sacrificing space for speed).

from consim.