How do I go to one frame forward or one frame back?

I have a cannon that needs to rotate on a pivot. Each side is a different picture, so on pressing left or right, I need the animation to know to go forward or back one frame. Thanks!

You can use this string:

self.animationframe+1

and

self.animationframe-1

Thank you! Works wonderfully. However, the cannon has 8 frames of rotation. Once it hits the last frame, it will not reset to frame 1. How do I do this so it can constantly cycle?

you can just make a condition:

on right pressed and animation frame is 8 set animation frame to 0

on left pressed and animation frame is 0 set animation frame to 8

or just use modulo

you can just make a condition:

on right pressed and animation frame is 8 set animation frame to 0

on left pressed and animation frame is 0 set animation frame to 8

I'm doing this now, although it skips frame 0 when going right, and right to 7. (Frames being 0-7)

What would be the proper way to sequence this? Thank you for all your help so far, by the way.

You can of course use modulo as madspy said <img src="{SMILIES_PATH}/icon_e_smile.gif" alt=":)" title="Smile">

Here is a capx of the first example.

https://dl.dropboxusercontent.com/u/100 ... rames.capx

Usually the on pressed trigger fires so quick that it effects the next frame as well so it skips a frame. By adding a wait 0.05 sec before every action fixes that. I did not place the events in the example as sub events so I could comment it nicely. But you can use sub events.

But the most effective way would be to do as MadSpy suggested.

on right arrow pressed: sprite set animation frame to (self.animationframe+1)%self.animationframecount

on left arrow pressed: sprite set animation frame to (self.animationframe+self.animationframecount-1)%self.animationframecount

You guys are wonderful! Thank you so much. Working perfectly now.

Nice, did you try MadSpys solution? It's pretty good to learn about modulo so it would be a good practice

I used the 2 codes he gave me and they worked! As far as Modulo, I am honestly not sure what that is, but I would love to learn.

% (modulo, remainder after division) https://www.scirra.com/manual/78/expressions

eg

0%4 = (0*4)+0 so returns 0

1%4 = (0*4)+1 so returns 1

2%4 = (0*4)+2 so returns 2

3%4 = (0*4)+3 so returns 3

4%4 = (1*4)+0 so returns 0

5%4 = (1*4)+1 so returns 1 etc etc

Note: animationframe can't be < 0 that's why you must add animationframecount before substract 1 to animationframe on 'left arrow pressed' condition