Canvas memory saturation (Bug?)

[abakoboParticipant]

The following code will throw a memory access violation after a some time. If the “New Canvas(im)” is not in a loop the memory will keep stable.
I could not find a Discard() method for canvases so I suppose it’s some GC but. (Or we’re not supposed to locally/loop New Canvases but that would be a bit strange)

Monkey

[crayon-5cb9d85c67fc3911225079 inline="true" ]Namespace myapp #Import "<std>" #Import "<mojo>" Using std.. Using mojo.. Class MyWindow Extends Window Field im:Image Field canv:Canvas Method New( title:String="Simple mojo app",width:Int=640,height:Int=480,flags:WindowFlags=Null ) Super.New( title,width,height,flags ) im=New Image (400,400) End Method OnRender( canvas:Canvas ) Override App.RequestRender() canv=New Canvas (im) 'if you put this line in constructor there won't be the problem canv.Clear (Color.White) canv.Color=Color.Black canv.DrawText( "Hello World!",10,10 ) canv.Flush() canvas.DrawImage (im,50,50) End End Function Main() New AppInstance New MyWindow App.Run() End

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[crayon-5cb9d85c67fc3911225079 inline="true" ]Namespace myapp   #Import "<std>" #Import "<mojo>"   Using std.. Using mojo..   Class MyWindow Extends Window   Field im:Image Field canv:Canvas   Method New( title:String="Simple mojo app",width:Int=640,height:Int=480,flags:WindowFlags=Null )   Super.New( title,width,height,flags ) im=New Image (400,400) End   Method OnRender( canvas:Canvas ) Override App.RequestRender()   canv=New Canvas (im) 'if you put this line in constructor there won't be the problem   canv.Clear (Color.White) canv.Color=Color.Black canv.DrawText( "Hello World!",10,10 ) canv.Flush() canvas.DrawImage (im,50,50)   End End   Function Main() New AppInstance New MyWindow App.Run() End

[/crayon]

[nerobotParticipant]

Why do you create new canvas each render frame?

Even if it will be removed by GC correctly – it looks like unnnecessary allocation.

[abakoboParticipant]

Why do you create new canvas each render frame?

I don’t, I just saw the bug(if it is) with some random simple test code.

[nobuyukiParticipant]

check this thread out, it may be helpful even though it’s old:  http://www.monkey-x.com/Community/posts.php?topic=9473&post=98448&view=all#98448

 

It relates to Images rather than Canvas but the notes on how the GC works near the end are probably still useful.

[abakoboParticipant]

Does this mean that canvas should discard the passed image!?

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