Threadsafe -> crash when Alt-Tab

[STARGÅTE]

Hi,

If I were the thread-safe mode for the Exe on, get this code is always an error in the debugger and when I wrote this off then a WIN-error when I use the ALT-TAB to go out screen, wants one could tell me why?

[ERROR] FlipBuffers()
[ERROR] Invalid memory access. (read error at address 64)

Code: Select all

InitSprite() 
InitSprite3D() 
InitKeyboard() 
InitMouse() 

OpenScreen(1024, 768, 32, "Screen") 
  
 CreateSprite(1,64,64, #PB_Sprite_Texture) 
 CreateSprite3D(1, 1) 
  
Repeat 

 FlipBuffers() 
 If IsScreenActive() 
  
  ClearScreen(0) 
  
  Start3D() 
   DisplaySprite3D(1,64,64) 
  Stop3D() 
   
  StartDrawing(ScreenOutput()) 
   DrawingMode(1) 
   DrawText(0,0,"Test", $FFFFFF) 
  StopDrawing() 
  
  ExamineMouse() 

  ExamineKeyboard() 
  If KeyboardPushed(#PB_Key_Escape) : End : EndIf 

 EndIf 


ForEver

My System:

Win XP SP3
PB 4.30 x86

[freak]

Isn't this the same as this one?
http://www.purebasic.fr/english/viewtopic.php?t=28676

People reported that as fixed with beta5. Is it still happening ?

[STARGÅTE]

No, it is not the same.
My code above crashes only when I thread-safe enabled and press Alt-Tab.
Without thread-safe, he runs without any problems.

I have just been discovered that was at the Sprite is, the code can thus be shortened:

Code: Select all

InitSprite() 
InitKeyboard() 

OpenScreen(1024, 768, 32, "Screen") 
  
 CreateSprite(1,64,64) 
  
Repeat 

 ClearScreen($808080) 
  DisplaySprite(1,64,64) 
 FlipBuffers() 
 
 ExamineKeyboard() 

Until KeyboardPushed(#PB_Key_Escape)

Alt-Tab with Thread-Safe --> crash at FlipBuffers, or win-error without Debugger
Alt-Tab without Thread-Safe --> run

[STARGÅTE]

The problem still exists in 4.4 B3, can anyone confirm

[gnasen]

same here

[netmaestro]

Same here. IsScreenActive() should help imho, but doesn't.

[STARGÅTE]

The problem has changed now, the program no longer crashes, but that I shall return no more into the screen!
And the program freezes!
No Debug-Output, No Error!

And even when the Threadsafe!

Here my Code:

Code: Select all

InitSprite()
InitSprite3D()
InitKeyboard()

ExamineDesktops() 
OpenScreen(DesktopWidth(0), DesktopHeight(0), 32, "Screen")
 
 CreateSprite(1,64,64, #PB_Sprite_Texture)
 CreateSprite3D(1, 1)
 
Repeat

 Delay(10)

 FlipBuffers()
 If IsScreenActive()
 
  ClearScreen(0)
 
  Start3D()
   DisplaySprite3D(1,64,64)
  Stop3D()
  
  StartDrawing(ScreenOutput())
   DrawingMode(1)
   DrawText(0,0,"Test", $FFFFFF)
  StopDrawing()

 EndIf
 
 ExamineKeyboard()
 If KeyboardPushed(#PB_Key_Escape) : End : EndIf

ForEver

What am I doing wrong?

SystemDatas:
WINDOWS XP (SP3), 1,8GHz P4, ATI - RADEON 9700, PB 4.40

[luis]

And the program freezes!

Actually it doesn't freeze, fails to restore the screen mode when switching back to it, but if you press escape the program quit nicely as expected.

Don't know what's wrong with your code, if anything is wrong. I don't have much experience with the directx part of pb, but looking at the docs it's seem to me your code should be ok.

[luis]

Using directx7 as subsystem it works, so it has something to do with the directx9 subsystem I suppose (now enabled by default on 4.40).

[PMV]

Just removed the Sprite3D calles to test if the behavior has
changed with the latest version (v5.20 Beta 10) ... but no
It does have the same behavior when threadsafe is not active,
the screen will not be restored.

Code: Select all

InitSprite()
InitKeyboard()

ExamineDesktops() 
OpenScreen(DesktopWidth(0), DesktopHeight(0), 32, "Screen")
 
 
Repeat

  Delay(100)
 FlipBuffers()
 If IsScreenActive()
   If ScreenActive = #False
     ScrenActive = #True
     CreateSprite(1,64,64)
   EndIf
   ClearScreen(0)
   Debug "Screen active"
   StartDrawing(SpriteOutput(1))
     Box(0, 0, 64, 64, 0)
     DrawingMode(1)
     DrawText(0,0,"Test", $FFFFFF)
    StopDrawing()
    DisplayTransparentSprite(1,64,64)
 Else
  ScreenActive = #False
 EndIf
 
 ExamineKeyboard()
 If KeyboardPushed(#PB_Key_Escape) : End : EndIf

ForEver