When "Wait 1 frame" in the source state of "Contact with Tile" is off, it is judged as no contact.

ACTION GAME MAKER BugReports
1

I made the enemy move in a certain direction, and if it was about to fall off a ledge, I displayed a falling animation and made it land. However, on flat ground without ledges, it started continuously playing the falling animation and stopped moving.

Upon investigation, I found that when the state action setting “Wait one frame” is turned off, the state transition condition “Contact with tile” (with contact condition inverted to mean “not in contact”) causes a transition even when contact is still occurring.

(The enemy object had this setting turned off to prevent momentary pauses in movement during branching logic.)

To reproduce this issue:
In the sample project ActionGameMansample1.0, turn off “Wait one frame” in the Wait state of ActionGameMan.vs.

Workarounds:

  • Turn “Wait one frame” back on, or
  • Add the condition “A certain amount of time has passed” to the transition link, setting it to at least 0.02 seconds.

ActionGameMan
ActionGameMan814×399 34.9 KB

2

To properly handle the timing of physics calculations, a new setting called “Wait 1 frame (is_allow_one_frame_to_pass)” has been added.

When set to OFF:
The “Contact with Tile” check is performed before the physics engine completes its update for that frame. As a result, collisions may not yet be registered, causing the game to incorrectly determine that the object is in mid-air.

When set to ON:
The process waits until the physics engine’s update is complete, ensuring that “Contact with Tile” correctly returns true.

In other words, when using physics-based checks such as “Contact with Tile” or “Wall Detection,” you must always keep “Wait 1 frame” enabled. Only disable it if you are performing purely variable-based calculations or logic that does not depend on collisions.

3

Thank you for the explanation; I now understand how it works.
I had turned off the state used for branching since it performs no processing,
and I will also pay attention to the conditions on the link side.

4

Sorry for the wait! We’ve fixed this issue in version 1.2.9 so it now works even when frame skipping is off!

5

Thank you for your assistance.
I have confirmed that the “Contact with Tile” condition works even when the “Wait 1 Frame” setting of the source state is turned OFF.