Calling GetGlyphOutline...

[C.M. Rouleau]

Anyone know why the latter GetGlyphOutline call tanks and produces a '...has encountered a problem and needs to close. We are sorry for the inconvenience' error?

The first call to GetGlyphOutline returns a buffer size of 380 in this case, so that call seems to work. The second call, however, doesn't like what I'm passing to it because I get the error mentioned above. BTW: How does one allocate a buffer of a particular size in PB if one doesn't know the size to begin with? My 'DIM buffer AS STRING*600' was an attempt to get something to work, but I'm sure there's a better way.

hScreenDC=GetDC(%NULL)
                        
point_size      =30
points_per_inch =72
pixels_per_inch =GetDeviceCaps(hScreenDC, %LOGPIXELSY)
                        
logical_height = -MulDiv(point_size, pixels_per_inch, points_per_inch)
                        
hFont=CreateFont(logical_height,0,0,0,0,%TRUE,0,0,%ANSI_CHARSET,0,0,0,0,"Times New Roman")
hOldFont=SelectObject(hScreenDC, hFont)
                        
DIM GlyphMets AS GLYPHMETRICS, xformation AS MAT2, bufferSize AS DWORD, bufferPointer AS STRING POINTER, buffer AS STRING*600
                        
xformation.eM11.value   =1
xformation.eM11.fract   =0
xformation.eM12.value   =0
xformation.eM12.fract   =0
xformation.eM21.value   =0
xformation.eM21.fract   =0
xformation.eM22.value   =1
xformation.eM22.fract   =0
                        
bufferSize      =0
bufferPointer   =%NULL
                                                
bufferSize=GetGlyphOutline(hScreenDC, ASC("A"), %GGO_NATIVE, GlyphMets, bufferSize, bufferPointer, xformation)
                        
MSGBOX FORMAT$(bufferSize)
                        
bufferPointer=VARPTR(buffer)
                        
GetGlyphOutline(hScreenDC, ASC("A"), %GGO_NATIVE, GlyphMets, bufferSize, bufferPointer, xformation)
                        
DeleteObject(SelectObject(hScreenDC, hOldFont))
ReleaseDC(%NULL,hScreenDC)

[Dominic Mitchell]

Here is a modified version of you code that works.

FUNCTION Form1_TextBtn1_Clicked _
  ( _
  BYVAL hWndParent  AS DWORD, _ ' handle of parent window
  BYVAL hWndCtrl    AS DWORD _  ' handle of control
  ) AS LONG

  LOCAL GlyphMets       AS GLYPHMETRICS
  LOCAL xformation      AS MAT2
  LOCAL bufferPointer   AS DWORD
  LOCAL hDC             AS DWORD
  LOCAL hFont           AS DWORD
  LOCAL hOldFont        AS DWORD
  LOCAL point_size      AS LONG
  LOCAL points_per_inch AS LONG
  LOCAL pixels_per_inch AS LONG
  LOCAL logical_height  AS LONG
  LOCAL bufferSize      AS DWORD

  hDC = GetDC(hWndParent)

  point_size      =30
  points_per_inch =72
  pixels_per_inch =GetDeviceCaps(hDC, %LOGPIXELSY)

  logical_height = -MulDiv(point_size, pixels_per_inch, points_per_inch)

  hFont = CreateFont(logical_height,0,0,0,0,%TRUE,0,0,%ANSI_CHARSET,0,0,0,0,"Times New Roman")
  hOldFont=SelectObject(hDC, hFont)

  xformation.eM11.value   =1
  xformation.eM11.fract   =0
  xformation.eM12.value   =0
  xformation.eM12.fract   =0
  xformation.eM21.value   =0
  xformation.eM21.fract   =0
  xformation.eM22.value   =1
  xformation.eM22.fract   =0

  bufferSize=GetGlyphOutline(hDC, ASC("A"), %GGO_NATIVE, GlyphMets, 0, BYVAL %NULL, xformation)
  MSGBOX FORMAT$(bufferSize)
  bufferPointer = HeapAlloc(GetProcessHeap(), %HEAP_ZERO_MEMORY, bufferSize)
  IF bufferPointer THEN
    IF GetGlyphOutline(hDC, ASC("A"), %GGO_NATIVE, GlyphMets, bufferSize, BYVAL bufferPointer, xformation) <> %GDI_ERROR THEN
      MSGBOX "success"
    END IF
    HeapFree GetProcessHeap(), 0, bufferPointer
  END IF

  DeleteObject(SelectObject(hDC, hOldFont))
  ReleaseDC(hWndParent,hDC)

END FUNCTION

[Dominic Mitchell]

The PowerBASIC Win32Api.inc file declares the lpBuffer as

lpBuffer AS ANY

The use of ANY in the include files is a pain in the ...
It would be nice if PB just drop the ANY keyword from all the includes.

[Michael Mattias]

Real Men Revel in "AS ANY."

[C.M. Rouleau]

Thanks, Dominic, it's crystal clear now.

-CMR