Problem with scrolling stars example

[Digitalic]

Try using the "Randomize" action...

I'm very happy to try the various options available for this type of effect, but my concern is that if I don't know why there is a problem with the method I have used, then it may cause me problems when using this type of movement in other applications that will converted to SWFs.

I would much rather know the cause of a bug than ignore it and find another solution; it stores up problems for the future!

[UrbanMonk]

I can almost guarantee the problem lies with the "wrap object" action.

Try this.

First remove the condition that checks if the stars are going off the top of the playarea.

Next add this condition and action:

If Y position of "star" is lower than 0 then
-Set Y position of "star" to 480
EDIT: whoops meant Y not X

Do that for all the stars and that should fix your problem.

[LB]

Just make sure you do not use compare two general values

[Digitalic]

I can almost guarantee the problem lies with the "wrap object" action.

To my surprise, your idea of setting X=640 if X<0 does not solve the problem (my stars are moving right to left); it was my first thought for a solution too! The stars still synchronise vertically.

I can't quite understand how they are synchronising under those circumstances.

Currently thinking about other possible solutions. Maybe setting a random position to the right of the screen. It's a bit messy though! I know how Actionscript deals with off-screen objects, but not so sure about MMF>SWF conversions.

[Digitalic]

Just make sure you do not use compare two general values

Thanks for your reply. I'm not sure how this relates to the problem I am having! Is there something I need to know. OK, there's lots that I need to know, but you know what I mean!

[UrbanMonk]

Ok, I just made a simple starfield that uses the bouncy ball movement and the bug isn't happening for me.

http://jfile.us/?id=3636ef

Tell me what's different with yours that could be causing the problem.


The bug did happen, but I had to leave it running for a while.

It seems like the stars are getting "caught" on the right for awhile, then all the sudden the flash runtime catches up with it's events and executes the action.

This takes a group of stars that are pass the wrap boundary and aligns them on the other side.

There is two ways to fix this.

1. Instead of setting the X position to 640 when it's position is less than 0 X. Just Add 660 to the position instead. Even if a group of stars manage to get beyond the wrap point before the repositioning action get executed they'll still be in the correct positions relative to one another rather than aligned.

2. Create new stars at a constant interval and destroy the ones that leave the side of the screen.

[Jacob]

Is there something I need to know. OK, there's lots that I need to know, but you know what I mean!

MMFs object selection only works when you select the object in the event editor. If it is in an expression, it doesn't work. So clicking on the object and comparing to an alterable value directly will make all actions pertain to the object with that alterable value. If you did compare two general values to compare the value, the actions will be applied to all of the objects.

[Digitalic]

1. Instead of setting the X position to 640 when it's position is less than 0 X. Just Add 660 to the position instead.

Have had the above configuration running for 1/2 hour without any issues being apparent.

I think this is the preferred method. I am now also randomising the Y position which prevents obvious 'patterns' of stars looping around the screen.

I don't know how MMF creates/destroys objects, but I suspect that there are greater overheads than simply changing the X,Y coordinates of an existing object.

Thanks.