Resizing of widows

[Ric]

I am trying to write a package similar to MS paint, but slightly more specific to my needs, the program uses asm to render to a DIBsection and I am using imglib to render images too.
I am calling a resizing routine with

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ON MOVE PROCresize(@msg%,@lparam%) : RETURN

and PROCresize code is

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      DEF PROCresize(action%,pixels%)

      IF action% <> 5 THEN ENDPROC
      screen_width% = pixels% AND &FFFF
      screen_height% = pixels% >>> 16

      bmi.Header.Size% = DIM(BITMAPINFOHEADER{})
      bmi.Header.Width% = screen_width%
      bmi.Header.Height% = screen_height%
      bmi.Header.Planes.l& = 1
      bmi.Header.BitCount.l& = 32
      SYS "CreateDIBSection", @memhdc%, bmi{}, 0, ^bits%, 0, 0 TO hbitmap%
      IF hbitmap%=0 ERROR 100, "Couldn't create DIBSection"
      SYS "SelectObject", @memhdc%, hbitmap% TO oldhbm%
      SYS "DeleteObject", oldhbm%
      SYS "InvalidateRect", @hwnd%, 0, 0

      VDU 23,22,screen_width%;screen_height%;10,20,16,0
      VDU 26
       PROC_imgInit
       PROConResize : REM(reset any variables that need to and re-render screen with imglib
      *FX 15,1

      ENDPROC

My program regularly crashes with some random variable that has been altered and badsubcript error occurs when accessing some of the arrays
Can someone please help to code the resize correctly
Kind regards Ric

[Richard Russell]

Can someone please help to code the resize correctly

If your suspicion is that the instability results from the asynchronous nature of the ON MOVE interrupt, set a global flag in the interrupt and act on it in your main code:

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DIM Resize%(2)
ON MOVE Resize%() = TRUE, @msg%, @lparam% : RETURN

Somewhere regularly executed in your main code:

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IF Resize%(0) Resize%(0) = FALSE : PROCresize(Resize%(1), Resize%(2)) 

That will ensure the resizing happens synchronously. If that doesn't fix the problem you will need to continue with debugging.

[Ric]

Thank you Richard, there was a little playing around to iron out a few anomalies but it worked a treat. It just leaves one question, does ON MOVE trap maximise and minimise, if not how do i do that?

[Richard Russell]

does ON MOVE trap maximise and minimise?

Maximise: yes, assuming the size actually changes. Minimise: not necessarily (it depends on the platform and possibly other factors); if minimise does trigger an ON MOVE interrupt the window size is likely to be reported as zero and should usually be ignored.

if not how do i do that?

Why would you want to trap minimise?

[Ric]

Thank you for the quick reply, it is all sorted now and the window can be resized, maximised and minimised.
I wanted to trap minimise so that i could tell the DIBsection not to renew.

[Richard Russell]

I wanted to trap minimise so that i could tell the DIBsection not to renew.

You shouldn't need a notification in order not to do something!