How do I make character stick to the walls/ceiling (platformer)? Kind of like spider-man does.

I tried to play with gravity, but it doesn't seem quite right (I'm a noob here).

Here is a screenshot:

I've seen some examples for ladders that swap from the platforming behaviour to the 8 direction behaviour ( set to up/down only ) when a ladder is activated. You could do something similar, but by having an invisible climbing surface on the edge of the wall.

+ Player_Base: Platform has wall to right

----+ Keyboard: → is down

----+ Player_Base: [X] Platform is on floor

-----> Player_Base: Set Platform max fall speed to 0

-----> Player_Base: Set Sliding to True

-----> Player_Base: Set animation frame to 1

----+ Keyboard: On → released

-----> Player_Base: Set Platform max fall speed to 1000

-----> Player_Base: Set Sliding to False

-----> Player_Base: Set animation frame to 0

+ Player_Base: Platform has wall to left

----+ Keyboard: ← is down

----+ Player_Base: [X] Platform is on floor

-----> Player_Base: Set Platform max fall speed to 0

-----> Player_Base: Set Sliding to True

-----> Player_Base: Set animation frame to 1

----+ Keyboard: On ← released

-----> Player_Base: Set Platform max fall speed to 1000

-----> Player_Base: Set Sliding to False

-----> Player_Base: Set animation frame to 0

+ Player_Base: [X] Platform has wall to right

+ Player_Base: [X] Platform has wall to left

-> Player_Base: Set Platform max fall speed to 1000

-> Player_Base: Set Sliding to False

-> Player_Base: Set animation frame to 0

+ Keyboard: On ↑ pressed

+ Player_Base: Is Sliding

-> Player_Base: Set Platform vector Y to -Self.Platform.JumpStrength × 1.25

-> Player_Base: Set Bounce to True

----+ Player_Base: Direction = "Right"

-----> Player_Base: Set Sliding to False

-----> Player_Base: Set Platform vector X to -Self.Platform.MaxSpeed × 5

----+ Player_Base: Direction = "Left"

-----> Player_Base: Set Sliding to False

-----> Player_Base: Set Platform vector X to Self.Platform.MaxSpeed × 5

Thanks for the advices. Some of the stuff is probably a bit too advanced for me. Not sure what do you mean by Sliding, Bounce and player_base_direction. Cant find it yet.

They are instance variables for the player. The bounce is just like in Kiwi Story - don't worry about it. The sliding is a Boolean, also used for animations. And the Direction you could just replace with the 'Is mirrored' condition.

I think u can look in rotating platform example, u can set gravity to player-90 and set player angle depend on your position to the solid object.