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William Leue
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Joined: 03/07/2020
Location: United States
Posts: 405

Posted: 03:19pm 02 Oct 2020

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I want to write a function that simply loops through all the sprites in an app and hides them. However, I quickly found that if a sprite is not visible, the SPRITE HIDE command throws an error.

Looking through the 5.05.05 documentation, I don't see a function that could be called to get this info. Maybe Peter might consider adding it to 5.05.06, something like

SPRITE(D,[#]n) Returns a 1 if the sprite is visible, 0 if not.

I guess another way to implement this idea is just to have SPRITE HIDE do nothing if the sprite is already hidden or not visible for some other reason.
-Bill

matherp
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Joined: 11/12/2012
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Posted: 03:22pm 02 Oct 2020

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SPRITE(X, [#]n) Returns the X-coordinate of sprite n. This function is only active when the sprite is currently displayed (active). Returns 10000 otherwise.

William Leue
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Joined: 03/07/2020
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Posted: 03:26pm 02 Oct 2020

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D'oh! I should learn to read ALL the text in the manual!

Thanks, Peter!
-Bill

William Leue
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Posted: 03:32pm 02 Oct 2020

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Well, hmmm. Even though I use SPRITE(X,n) <> 10000 to test whether the nth sprite is visible, I still get the 'ERROR: not showing' error.

I am still on 5.05.03. Is it possible the SPRITE(X,n) function is buggy in that version?

-Bill

matherp
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Posted: 03:36pm 02 Oct 2020

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Quote I am still on 5.05.03. Is it possible the SPRITE(X,n) function is buggy in that version?

Works on 5.05.06b15. Can't remember when/if fixed

vegipete

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Joined: 29/01/2013
Location: Canada
Posts: 1132

Posted: 04:46pm 02 Oct 2020

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I too get way too many 'ERROR: not showing' messages with sprites. So much so that I've taken to parking all my sprites at (MM.HRES-1,MM.VRES-1) and never hiding them.

If SPRITE HIDE can't hide hidden sprites, perhaps I'll try with an ON ERROR SKIP statement just before.

==============
Didn't SPRITE(X,n) return -1 for a while for hidden sprites?
Edited 2020-10-03 02:46 by vegipete

Visit Vegipete's *Mite Library for cool programs.

capsikin
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Joined: 30/06/2020
Location: Australia
Posts: 341

Posted: 09:48am 12 Oct 2020

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matherp said

Quote I am still on 5.05.03. Is it possible the SPRITE(X,n) function is buggy in that version?

Yes. I suggest you don't try to use the buggy output for checking when the sprite is active, or it will stop working on newer fixed firmware.

If you want code that works in older firmware, you can check SPRITE(L, [#]n) and compare it to -1. It is -1 if the sprite is not active (as is the buggy SPRITE(X,n)).

Quote
Works on 5.05.06b15. Can't remember when/if fixed

I know it was fixed some time after 5.05.04.

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