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Index › Programming Questions & Help › Syntax Questions › Save current screen to PGraphics container
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Save current screen to PGraphics container (Read 494 times)
johnali3n
Save current screen to PGraphics container
Jul 7th, 2009, 8:48am  
Hi,

I am creating a paint program and was trying to implement an UNDO feature.

I tried saving the current image to a file and reloading but the save and load to JPG takes too long, up to 5 seconds, and makes the program unusable.

I was wondering if I could use a PGraphics variable:-



But, instead of using undo.line, I would somehow grab the current image?

Anyone got any ideas or suggestions please? :)
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blindfish
Re: Save current screen to PGraphics container
Reply #1 - Jul 7th, 2009, 8:59am  
I'd guess you might want to just copy data from the pixels[] array (also see loadPixels()).

I'd guess the most efficient approach would be to record only the previous values of pixels that are changed during a given action, perhaps using an ArrayList...  You should then be able to set() them back when undo is called.

I suspect grabbing the whole image each time a change is made may prove slow - though that will no doubt depend on the canvas size.
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Where is the what if the what is in why?
 
PhiLho 
Re: Save current screen to PGraphics container
Reply #2 - Jul 7th, 2009, 9:02am  
Woah, the forum is not responsive today, multiple posts galore! Hint: go to each extra message and delete it from there.

Look at get() to capture the current sketch display to a PImage.
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« Last Edit: Jul 7th, 2009, 11:03pm by PhiLho  »  
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