I am aware, and your solution looks good. Deprojection is common when you want to get a position under the cursor (3D). Input axis is common when you just want to register left / right movement which seems to be the case here. I mentioned deprojection specifically because the question mentioned mouse to coordinate conversion. deprojection might give a more natural feeling if the movement speed matches the mouse speed you are used to, but it’s up to preference. If the game is going to be controlled with both WASD and the mouse, you optimally want to provide the same experience for both to not give an advantage with one or the other. Snapping the movement to mouse position would give a large advantage over wasd movement in which case you might consider not using deprojection.