How do I track the position of an actor properly?

h.rashid13

Currently, I have a timer that, every 0 seconds, sets a Game variable to the current position of my actor (both x and y). Then I have a mask that is supposed to track the actor with the constrain attribute.

However, when the actor moves to a certain point in the scene (3/4 of the way to the right or 3/4 of the way up), the mask starts to move differently. I have attached the project I was working on when this happened. The actor that the mask is supposed to track is Frank.

http://www.mediafire.com/download.php?jctxycwpjqmn8g0

beefy_clyro

@h.rashid13

Whose a silly fella then?

Really easy fix ....

Ready .....

Move your mask actor off of the HUD layer, down onto the scrollable layer where Frank is

SnapFireStudios

@h.rashid13 - Hey, this should answer your question. Instead of having a timer that changes the variable every 0 seconds, use the 'Constrain attribute' behavior. So, constrain game.xpos to self.position.x. The same goes for y.
Then you can tap in to the game.xpos variable wherever you need.

Hope that helps,
- Thomas

beefy_clyro

@h.rashid13 @SnapFireStudio

I would probably go with what Thomas has said. So constrain the mask to game attributes and then constrain the actual character to the game attributes ...

Alternatively, you can cut out one set of constrains by unlocking the prototype into an instance (your character) and then you can constrain the players self.position to scene > Layers > Correct Layer > Mask

This can save you constraining the mask to game attributes

h.rashid13

@beefy_clyro @SnapFireStudio

I tried out constraining the the mask to Game and constraining Game to the actor, but the mask is still exhibiting the odd movement.

If you tried to play the game, you'd notice that as you move right, the mask will suddenly move farther right than the actor. I feel as though gamesalad is not reading the actor's position correctly.

beefy_clyro

Just to confirm

game.maskX to self.positionX of mask
game.maskY to self.positionY of mask

self.positionX to game.maskX in character
self.positionY to game.maskY in character

That would work fine .. unless you have some conflicting rules somewhere.

I went to look at your project but its in windows format and I dont have the converting method.

h.rashid13

@beefy_clyro

tried to export for mac

http://www.mediafire.com/download.php?e4jiasougjvalkd

h.rashid13

Wait. The game.mask variables are currently integers. Should they be set to real instead?

beefy_clyro

If they're slightly out then they should be real, integers will just round it up in whole pixels

SnapFireStudios

Yep, real attributes are best for this type of thing.
- Thomas

beefy_clyro

Just had a quick look and its not that causing the problem ... Hard for me to look at the mo, got some video conversions on the go and its killing my computers performance

SnapFireStudios

@beefy_clyro - That's pretty much the feeling I get when I am trying to fix a bug for 2 hours and then I open up the otherwise section... (
- Thomas

beefy_clyro

Haha I know the feeling all too well .. I'm much better nowadays as after numerous projects and 3+ years of using GS, I have a pretty decent structure now and I now know 'how I think' ... This makes tracking down where things will be put a lot easier )

h.rashid13

Ah! Thank you so much! Fixed the mask issue!

beefy_clyro

No worries, good luck with the rest of your game