Top Down Collision Code

//Horizontal collision
if place_meeting(x + hsp, y, obj_wall)
{
    while !place_meeting(x + sign(hsp), y, obj_wall)
    {
        x += sign(hsp);
    }
    hsp = 0;
}
x += hsp;

//Vertical collision
if place_meeting(x, y + vsp, obj_wall)
{
    while !place_meeting(x, y + sign(vsp), obj_wall)
    {
        y += sign(vsp);
    }
    vsp = 0;
}
y += vsp;