cPS in bPainted

[Enrico Maria Giordano]

It seems that cPS parameter provided to bPainted doesn't have the expected data. Can you confirm this? If yes, any fix?

EMG

[Antonio Linares]

Enrico,

It should have it as see how it gets built:

Code: Select all  Expand view

HB_FUNC( BEGINPAINT ) // ( hWnd, @cPS ) --> hDC
{
   PAINTSTRUCT ps;
   HDC hDC   = BeginPaint( ( HWND ) hb_parnl( 1 ), &ps );

   hb_storclen( ( char * ) &ps, sizeof( PAINTSTRUCT ), 2 );
   hb_retnl( ( LONG ) hDC );
}

[Antonio Linares]

Enrico,

There is a working example managing cPS at FWH\samples\formdes.prg

[Enrico Maria Giordano]

Antonio,

Enrico,

There is a working example managing cPS at FWH\samples\formdes.prg

That's exactly what I was trying to do but unfortunately DrawGrid() makes no use of cPS parameter.

EMG

[Antonio Linares]

Enrico,

Have you tried to modify DrawGrid() this way ?

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HB_FUNC( DRAWGRID ) // hWnd, hDC, @cPS, wGridX, wGridY
{
   WORD wRow, wCol;
   #ifdef _WIN64
      HDC hDC   = ( HDC ) hb_parnll( 2 );
      HWND hWnd = ( HWND ) hb_parnll( 1 );
   #else  
      HDC hDC   = ( HDC ) hb_parnl( 2 );
      HWND hWnd = ( HWND ) hb_parnl( 1 );
   #endif
   WORD wGridX = hb_parni( 4 );
   WORD wGridY = hb_parni( 5 );
   RECT rc;
   WORD wWidth, wHeight;
   PAINTSTRUCT ps;
   
   memcpy( &ps, hb_parc( 3 ), sizeof( PAINTSTRUCT ) );

   GetWindowRect( hWnd, &rc );
   wWidth  = rc.right - rc.left + 1;
   wHeight = rc.bottom - rc.top + 1;

   for( wRow = 0; wRow <= wHeight; wRow += wGridX )
      for( wCol = 0; wCol <= wWidth; wCol += wGridY )
         SetPixel( hDC, wCol, wRow, 0 );
}
 

[Enrico Maria Giordano]

Antonio,

Enrico,

Have you tried to modify DrawGrid() this way ?

Yes, but ps.rcPaint.top and ps.rcPaint.left are always zero, unless I'm missing something.

EMG

[Antonio Linares]

Enrico,

ps.rcPaint.bottom and ps.rcPaint.right are non zero, so they seem valid.

Going to check top and left...

[Antonio Linares]

Enrico,

They are zero but this code seems to work fine:

Code: Select all  Expand view

HB_FUNC( DRAWGRID ) // hWnd, hDC, @cPS, wGridX, wGridY
{
   WORD wRow, wCol;
   #ifdef _WIN64
      HDC hDC   = ( HDC ) hb_parnll( 2 );
      HWND hWnd = ( HWND ) hb_parnll( 1 );
   #else  
      HDC hDC   = ( HDC ) hb_parnl( 2 );
      HWND hWnd = ( HWND ) hb_parnl( 1 );
   #endif
   WORD wGridX = hb_parni( 4 );
   WORD wGridY = hb_parni( 5 );
   PAINTSTRUCT ps;
   
   memcpy( &ps, hb_parc( 3 ), sizeof( PAINTSTRUCT ) );

   for( wRow = 0; wRow <= ps.rcPaint.bottom; wRow += wGridX )
      for( wCol = 0; wCol <= ps.rcPaint.right; wCol += wGridY )
         SetPixel( hDC, wCol, wRow, 0 );
}

[Enrico Maria Giordano]

Antonio,

Enrico,

They are zero but this code seems to work fine:

Yes, but the benefit is greatly reduced if the area to be repainted always starts from 0, 0...

EMG

[Antonio Linares]

That is what Windows is providing us

[Enrico Maria Giordano]

Antonio,

That is what Windows is providing us

I'm not so sure... how FWH provides cPS to bPainted codeblock?

EMG

[Antonio Linares]

Enrico,

cPS is obtained here:

Code: Select all  Expand view

METHOD _BeginPaint() CLASS TWindow

   local cPS

   if ::nPaintCount == nil
      ::nPaintCount = 1
   else
      ::nPaintCount++
   endif

   ::hDC = BeginPaint( ::hWnd, @cPS )
   ::cPS = cPS

return nil

and used from bPainted:

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     if ValType( ::bPainted ) == "B"
         uVal = Eval( ::bPainted, ::hDC, ::cPS, Self )
      endif

[Enrico Maria Giordano]

Antonio,

Enrico,

cPS is obtained here:

Code: Select all  Expand view

METHOD _BeginPaint() CLASS TWindow

   local cPS

   if ::nPaintCount == nil
      ::nPaintCount = 1
   else
      ::nPaintCount++
   endif

   ::hDC = BeginPaint( ::hWnd, @cPS )
   ::cPS = cPS

return nil

and used from bPainted:

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     if ValType( ::bPainted ) == "B"
         uVal = Eval( ::bPainted, ::hDC, ::cPS, Self )
      endif

It looks correct, thank you. Any ideas on how to speed up DrawGrid() function?

EMG

[Antonio Linares]

Enrico,

Here it seems fast enough, I am using a Core 2 Duo

It could be speed up using a brush instead of calling SetPixel()

[Enrico Maria Giordano]

Antonio,

Enrico,

Here it seems fast enough, I am using a Core 2 Duo

It could be speed up using a brush instead of calling SetPixel()

Interesting... any little sample?

EMG