I did this with relative ease by putting my one-way platforms on a separate tile-map as I think there currently is a bug with having different physics settings on different layers within a tile-map. So start with placing the platforms you want to jump through on a separate map, then on that map adjust the physics settings to the following.
So create a new Physics Object like so:
Setup the tilemap that has your platforms on:
My character also has block all on everything:
Now I change the collision from block to overlap when my character jumps using the Event On Jumped, as you can see the channel is set to platforms so everything using the physics object “Platforms” will now let things pass through and generate an Overlap event. The capsule component is the characters own collider.
I do a check to see if my character is falling and if he is I change collision on the channel to block. You can see I’m doing a check too see if I’m currently passing through a platform as without it I was getting stuck halfway through, the check is below.
Just a simple bool set on overlap events.
Not sure if this is the best way but I didn’t want to create triggers under every platform by hand and the result is something like the following. Any issue’s let me know.