_PUTIMAGE Question

[TempodiBasic]

Hi Terry,
Hi Steve

I have found this wiki example in which _PUTIMAGE works with hardware images ... AND in this code there is no _DestHandle&.
Before reading Steve's answer I have thought that it was because _DEST 0 is screen in use and displayed as output.
Now I am asking to myself if the absence of _destHandle& is a tip or a coincidence.

Code: (Select All)

SCREEN _NEWIMAGE(640, 480, 32)

'create some software screens
scr_bg = _NEWIMAGE(640, 480, 32)
scr_fg = _NEWIMAGE(50, 50, 32)

'draw to the background one, and make a nice pattern
_DEST scr_bg
FOR i = 1 TO 100
    LINE (RND * 640, RND * 480)-(RND * 640, RND * 480), _RGBA32(RND * 255, RND * 255, RND * 255, RND * 255), BF
NEXT i
'create a hardware screen version of the background
scrh_bg = _COPYIMAGE(scr_bg, 33)
_FREEIMAGE scr_bg 'we no longer need the software version in memory

'then do the same thing for the foreground
_DEST scr_fg
LINE (0, 0)-(50, 50), _RGBA32(255, 255, 255, 200), BF
'copy to hardware screen
scrh_fg = _COPYIMAGE(scr_fg, 33)
_FREEIMAGE scr_fg 'and free software screen from memory

'set image destination to main screen
_DEST 0
_DISPLAYORDER _HARDWARE 'do not even render the software layer, just the hardware one.
DO 'main program loop
    '_putimage knows these are hardware screens, so destination of 0 is taken as hardware layer
    _PUTIMAGE , scrh_bg
    _PUTIMAGE (x, y), scrh_fg
    'just some input processing
    k = _KEYHIT
    SELECT CASE k
        CASE ASC("w"): y = y - 1
        CASE ASC("a"): x = x - 1
        CASE ASC("s"): y = y + 1
        CASE ASC("d"): x = x + 1
    END SELECT
    _DISPLAY 'render image after changes
    _LIMIT 30 'we're doing all this at 30 cycles/second
LOOP

taken from this wiki page Hardware images.

well Step 1:
we create an image surface on which we put the hardware images
and from this last image we _Putimage on the screen (_Dest 0)

and there is no issue

Code: (Select All)

Screen _NewImage(640, 480, 32)

'create some software screens
scr_bg = _NewImage(640, 480, 32)
scr_fg = _NewImage(50, 50, 32)

'draw to the background one, and make a nice pattern
_Dest scr_bg
For i = 1 To 100
    Line (Rnd * 640, Rnd * 480)-(Rnd * 640, Rnd * 480), _RGBA32(Rnd * 255, Rnd * 255, Rnd * 255, Rnd * 255), BF
Next i
'create a hardware screen version of the background
scrh_bg = _CopyImage(scr_bg, 33)
_FreeImage scr_bg 'we no longer need the software version in memory

'then do the same thing for the foreground
_Dest scr_fg
Line (0, 0)-(50, 50), _RGBA32(255, 255, 255, 200), BF
'copy to hardware screen
scrh_fg = _CopyImage(scr_fg, 33)
_FreeImage scr_fg 'and free software screen from memory

'set image destination to main screen
Dim ScreenC As Long
_Dest ScreenC
'_Dest 0
_DisplayOrder _Hardware 'do not even render the software layer, just the hardware one.
Do 'main program loop
    '_putimage knows these are hardware screens, so destination of 0 is taken as hardware layer
    _PutImage , scrh_bg
    _PutImage (x, y), scrh_fg
    _PutImage (0, 0), ScreenC, 0
    'just some input processing
    k = _KeyHit
    Select Case k
        Case Asc("w"): y = y - 1
        Case Asc("a"): x = x - 1
        Case Asc("s"): y = y + 1
        Case Asc("d"): x = x + 1
    End Select
    _Display 'render image after changes
    _Limit 30 'we're doing all this at 30 cycles/second
Loop

moreover we attempt to _putimage the hardware images directly on a software image and then we copy this last on the screen surface...
(we  delete _Dest 0 and _Dysplayorder instructions!)  and all seem working well!

Code: (Select All)

Screen _NewImage(640, 480, 32)

'create some software screens
scr_bg = _NewImage(640, 480, 32)
scr_fg = _NewImage(50, 50, 32)

'draw to the background one, and make a nice pattern
_Dest scr_bg
For i = 1 To 100
    Line (Rnd * 640, Rnd * 480)-(Rnd * 640, Rnd * 480), _RGBA32(Rnd * 255, Rnd * 255, Rnd * 255, Rnd * 255), BF
Next i
'create a hardware screen version of the background
scrh_bg = _CopyImage(scr_bg, 33)
_FreeImage scr_bg 'we no longer need the software version in memory

'then do the same thing for the foreground
_Dest scr_fg
Line (0, 0)-(50, 50), _RGBA32(255, 255, 255, 200), BF
'copy to hardware screen
scrh_fg = _CopyImage(scr_fg, 33)
_FreeImage scr_fg 'and free software screen from memory

'set image destination to software image that has been copied on the main screen
Dim ScreenC As Long
Do 'main program loop
    '_putimage knows these are hardware screens, so destination of 0 is taken as hardware layer
    _PutImage , scrh_bg, ScreenC
    _PutImage (x, y), scrh_fg, ScreenC
    _PutImage (0, 0), ScreenC, 0
    'just some input processing
    k = _KeyHit
    Select Case k
        Case Asc("w"): y = y - 1
        Case Asc("a"): x = x - 1
        Case Asc("s"): y = y + 1
        Case Asc("d"): x = x + 1
    End Select
    _Display 'render image after changes
    _Limit 30 'we're doing all this at 30 cycles/second
Loop

we need more informations !
Why does Terry get invalid handle error and this code no?