Since I didn't get the desired results with the fix ChaosMaker gave me in my game engine I thought I might try making square tiles which are 15x15 in size (so checks are always made from the exact center).
This didn't work either and some tiles are visible while the same tile but at the opposite x or y direction from the player is not.
Am I missing something or is the collision_line in GM a bit broken in this way?
Here is the example as well as code:
Is there a good replacement for collision_line or does anybody have any other suggestions?