1 ///////////////////////////////////////////////////////////////////////////// 
   3 // Purpose:     wxGLCanvas, for using OpenGL with wxWindows under MS Windows 
   4 // Author:      Julian Smart 
   8 // Copyright:   (c) Julian Smart 
   9 // Licence:       wxWindows licence 
  10 ///////////////////////////////////////////////////////////////////////////// 
  13 #pragma implementation "glcanvas.h" 
  16 #include "wx/wxprec.h" 
  18 #if defined(__BORLANDC__) 
  26 #define wxUSE_GLCANVAS 1 
  33 #include <wx/msw/private.h> 
  34 #include <wx/settings.h> 
  37 #include "myglcanvas.h" 
  39 static const wxChar 
*wxGLCanvasClassName 
= wxT("wxGLCanvasClass"); 
  40 static const wxChar 
*wxGLCanvasClassNameNoRedraw 
= wxT("wxGLCanvasClassNR"); 
  42 LRESULT WXDLLEXPORT APIENTRY _EXPORT 
wxWndProc(HWND hWnd
, UINT message
, 
  43                                    WPARAM wParam
, LPARAM lParam
); 
  46  * GLContext implementation 
  49 wxGLContext::wxGLContext(bool isRGB
, wxGLCanvas 
*win
, const wxPalette
& palette
) 
  53   m_hDC 
= win
->GetHDC(); 
  55   m_glContext 
= wglCreateContext((HDC
) m_hDC
); 
  56   wxCHECK_RET( m_glContext
, wxT("Couldn't create OpenGl context") ); 
  58   wglMakeCurrent((HDC
) m_hDC
, m_glContext
); 
  61 wxGLContext::wxGLContext( 
  62                bool isRGB
, wxGLCanvas 
*win
, 
  63                const wxPalette
& palette
, 
  64                const wxGLContext 
*other  
/* for sharing display lists */ 
  69   m_hDC 
= win
->GetHDC(); 
  71   m_glContext 
= wglCreateContext((HDC
) m_hDC
); 
  72   wxCHECK_RET( m_glContext
, wxT("Couldn't create OpenGl context") ); 
  75     wglShareLists( other
->m_glContext
, m_glContext 
); 
  77   wglMakeCurrent((HDC
) m_hDC
, m_glContext
); 
  80 wxGLContext::~wxGLContext() 
  84     wglMakeCurrent(NULL
, NULL
); 
  85     wglDeleteContext(m_glContext
); 
  89 void wxGLContext::SwapBuffers() 
  93     wglMakeCurrent((HDC
) m_hDC
, m_glContext
); 
  94     ::SwapBuffers((HDC
) m_hDC
);    //blits the backbuffer into DC 
  98 void wxGLContext::SetCurrent() 
 102     wglMakeCurrent((HDC
) m_hDC
, m_glContext
); 
 106   setupPixelFormat(hDC); 
 111 void wxGLContext::SetColour(const char *colour
) 
 116   wxColour 
*col 
= wxTheColourDatabase
->FindColour(colour
); 
 119     r 
= (float)(col
->Red()/256.0); 
 120     g 
= (float)(col
->Green()/256.0); 
 121     b 
= (float)(col
->Blue()/256.0); 
 128  * wxGLCanvas implementation 
 131 IMPLEMENT_CLASS(wxGLCanvas
, wxWindow
) 
 133 BEGIN_EVENT_TABLE(wxGLCanvas
, wxWindow
) 
 134     EVT_SIZE(wxGLCanvas::OnSize
) 
 135     EVT_PALETTE_CHANGED(wxGLCanvas::OnPaletteChanged
) 
 136     EVT_QUERY_NEW_PALETTE(wxGLCanvas::OnQueryNewPalette
) 
 139 wxGLCanvas::wxGLCanvas(wxWindow 
*parent
, wxWindowID id
, 
 140     const wxPoint
& pos
, const wxSize
& size
, long style
, const wxString
& name
, 
 141     int *attribList
, const wxPalette
& palette
) : wxWindow() 
 143   m_glContext 
= (wxGLContext
*) NULL
; 
 145   bool ret 
= Create(parent
, id
, pos
, size
, style
, name
); 
 149     SetBackgroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_3DFACE
)); 
 150     SetFont(wxSystemSettings::GetFont(wxSYS_DEFAULT_GUI_FONT
)); 
 153   m_hDC 
= (WXHDC
) ::GetDC((HWND
) GetHWND()); 
 155   SetupPixelFormat(attribList
); 
 156   SetupPalette(palette
); 
 158   m_glContext 
= new wxGLContext(TRUE
, this, palette
); 
 161 wxGLCanvas::wxGLCanvas( wxWindow 
*parent
, 
 162               const wxGLContext 
*shared
, wxWindowID id
, 
 163               const wxPoint
& pos
, const wxSize
& size
, long style
, const wxString
& name
, 
 164               int *attribList
, const wxPalette
& palette 
) 
 167   m_glContext 
= (wxGLContext
*) NULL
; 
 169   bool ret 
= Create(parent
, id
, pos
, size
, style
, name
); 
 173     SetBackgroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_3DFACE
)); 
 174     SetFont(wxSystemSettings::GetFont(wxSYS_DEFAULT_GUI_FONT
)); 
 177   m_hDC 
= (WXHDC
) ::GetDC((HWND
) GetHWND()); 
 179   SetupPixelFormat(attribList
); 
 180   SetupPalette(palette
); 
 182   m_glContext 
= new wxGLContext(TRUE
, this, palette
, shared 
); 
 185 // Not very useful for wxMSW, but this is to be wxGTK compliant 
 187 wxGLCanvas::wxGLCanvas( wxWindow 
*parent
, const wxGLCanvas 
*shared
, wxWindowID id
, 
 188                         const wxPoint
& pos
, const wxSize
& size
, long style
, const wxString
& name
, 
 189                         int *attribList
, const wxPalette
& palette 
): 
 192   m_glContext 
= (wxGLContext
*) NULL
; 
 194   bool ret 
= Create(parent
, id
, pos
, size
, style
, name
); 
 198     SetBackgroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_3DFACE
)); 
 199     SetFont(wxSystemSettings::GetFont(wxSYS_DEFAULT_GUI_FONT
)); 
 202   m_hDC 
= (WXHDC
) ::GetDC((HWND
) GetHWND()); 
 204   SetupPixelFormat(attribList
); 
 205   SetupPalette(palette
); 
 207   wxGLContext 
*sharedContext
=0; 
 208   if (shared
) sharedContext
=shared
->GetContext(); 
 209   m_glContext 
= new wxGLContext(TRUE
, this, palette
, sharedContext 
); 
 212 wxGLCanvas::~wxGLCanvas() 
 217   ::ReleaseDC((HWND
) GetHWND(), (HDC
) m_hDC
); 
 220 // Replaces wxWindow::Create functionality, since we need to use a different 
 222 bool wxGLCanvas::Create(wxWindow 
*parent
, 
 227                         const wxString
& name
) 
 229   static bool s_registeredGLCanvasClass 
= FALSE
; 
 231   // We have to register a special window class because we need 
 232   // the CS_OWNDC style for GLCanvas. 
 235   From Angel Popov <jumpo@bitex.com> 
 237   Here are two snips from a dicussion in the OpenGL Gamedev list that explains 
 238   how this problem can be fixed: 
 240   "There are 5 common DCs available in Win95. These are aquired when you call 
 241   GetDC or GetDCEx from a window that does _not_ have the OWNDC flag. 
 242   OWNDC flagged windows do not get their DC from the common DC pool, the issue 
 243   is they require 800 bytes each from the limited 64Kb local heap for GDI." 
 245   "The deal is, if you hold onto one of the 5 shared DC's too long (as GL apps 
 246   do), Win95 will actually "steal" it from you.  MakeCurrent fails, 
 247   apparently, because Windows re-assigns the HDC to a different window.  The 
 248   only way to prevent this, the only reliable means, is to set CS_OWNDC." 
 251   if (!s_registeredGLCanvasClass
) 
 255     // the fields which are common to all classes 
 256     wndclass
.lpfnWndProc   
= (WNDPROC
)wxWndProc
; 
 257     wndclass
.cbClsExtra    
= 0; 
 258     wndclass
.cbWndExtra    
= sizeof( DWORD 
); // VZ: what is this DWORD used for? 
 259     wndclass
.hInstance     
= wxhInstance
; 
 260     wndclass
.hIcon         
= (HICON
) NULL
; 
 261     wndclass
.hCursor       
= ::LoadCursor((HINSTANCE
)NULL
, IDC_ARROW
); 
 262     wndclass
.lpszMenuName  
= NULL
; 
 264     // Register the GLCanvas class name 
 265     wndclass
.hbrBackground 
= (HBRUSH
)NULL
; 
 266     wndclass
.lpszClassName 
= wxGLCanvasClassName
; 
 267     wndclass
.style         
= CS_HREDRAW 
| CS_VREDRAW 
| CS_DBLCLKS 
| CS_OWNDC
; 
 269     if ( !::RegisterClass(&wndclass
) ) 
 271       wxLogLastError(wxT("RegisterClass(wxGLCanvasClass)")); 
 275     // Register the GLCanvas class name for windows which don't do full repaint 
 277     wndclass
.lpszClassName 
= wxGLCanvasClassNameNoRedraw
; 
 278     wndclass
.style        
&= ~(CS_HREDRAW 
| CS_VREDRAW
); 
 280     if ( !::RegisterClass(&wndclass
) ) 
 282         wxLogLastError(wxT("RegisterClass(wxGLCanvasClassNameNoRedraw)")); 
 284         ::UnregisterClass(wxGLCanvasClassName
, wxhInstance
); 
 289     s_registeredGLCanvasClass 
= TRUE
; 
 292   wxCHECK_MSG( parent
, FALSE
, wxT("can't create wxWindow without parent") ); 
 294   if ( !CreateBase(parent
, id
, pos
, size
, style
, wxDefaultValidator
, name
) ) 
 297   parent
->AddChild(this); 
 300   if ( style 
& wxBORDER 
) 
 301     msflags 
|= WS_BORDER
; 
 302   if ( style 
& wxTHICK_FRAME 
) 
 303     msflags 
|= WS_THICKFRAME
; 
 306   A general rule with OpenGL and Win32 is that any window that will have a 
 307   HGLRC built for it must have two flags:  WS_CLIPCHILDREN & WS_CLIPSIBLINGS. 
 308   You can find references about this within the knowledge base and most OpenGL 
 309   books that contain the wgl function descriptions. 
 312   msflags 
|= WS_CHILD 
| WS_VISIBLE 
| WS_CLIPSIBLINGS 
| WS_CLIPCHILDREN
; 
 315   WXDWORD exStyle 
= Determine3DEffects(WS_EX_CLIENTEDGE
, &want3D
); 
 317   // Even with extended styles, need to combine with WS_BORDER 
 318   // for them to look right. 
 319   if ( want3D 
|| (m_windowStyle 
& wxSIMPLE_BORDER
) || (m_windowStyle 
& wxRAISED_BORDER 
) || 
 320        (m_windowStyle 
& wxSUNKEN_BORDER
) || (m_windowStyle 
& wxDOUBLE_BORDER
)) 
 322     msflags 
|= WS_BORDER
; 
 325   return MSWCreate(wxGLCanvasClassName
, NULL
, pos
, size
, msflags
, exStyle
); 
 328 static void AdjustPFDForAttributes(PIXELFORMATDESCRIPTOR
& pfd
, int *attribList
) 
 331     pfd
.dwFlags 
&= ~PFD_DOUBLEBUFFER
; 
 332     pfd
.iPixelType 
= PFD_TYPE_COLORINDEX
; 
 336     while( (attribList
[arg
]!=0) ) 
 338       switch( attribList
[arg
++] ) 
 341           pfd
.iPixelType 
= PFD_TYPE_RGBA
; 
 343         case WX_GL_BUFFER_SIZE
: 
 344           pfd
.cColorBits 
= attribList
[arg
++]; 
 347           // this member looks like it may be obsolete 
 348           if (attribList
[arg
] > 0) { 
 349             pfd
.iLayerType 
= (BYTE
)PFD_OVERLAY_PLANE
; 
 350           } else if (attribList
[arg
] < 0) { 
 351             pfd
.iLayerType 
= (BYTE
)PFD_UNDERLAY_PLANE
; 
 353             pfd
.iLayerType 
= (BYTE
)PFD_MAIN_PLANE
; 
 357         case WX_GL_DOUBLEBUFFER
: 
 358           pfd
.dwFlags 
|= PFD_DOUBLEBUFFER
; 
 361           pfd
.dwFlags 
|= PFD_STEREO
; 
 363         case WX_GL_AUX_BUFFERS
: 
 364           pfd
.cAuxBuffers 
= attribList
[arg
++]; 
 367           pfd
.cColorBits 
+= (pfd
.cRedBits 
= attribList
[arg
++]); 
 369         case WX_GL_MIN_GREEN
: 
 370           pfd
.cColorBits 
+= (pfd
.cGreenBits 
= attribList
[arg
++]); 
 373           pfd
.cColorBits 
+= (pfd
.cBlueBits 
= attribList
[arg
++]); 
 375         case WX_GL_MIN_ALPHA
: 
 376           // doesn't count in cColorBits 
 377           pfd
.cAlphaBits 
= attribList
[arg
++]; 
 379         case WX_GL_DEPTH_SIZE
: 
 380           pfd
.cDepthBits 
= attribList
[arg
++]; 
 382         case WX_GL_STENCIL_SIZE
: 
 383           pfd
.cStencilBits 
= attribList
[arg
++]; 
 385         case WX_GL_MIN_ACCUM_RED
: 
 386           pfd
.cAccumBits 
+= (pfd
.cAccumRedBits 
= attribList
[arg
++]); 
 388         case WX_GL_MIN_ACCUM_GREEN
: 
 389           pfd
.cAccumBits 
+= (pfd
.cAccumGreenBits 
= attribList
[arg
++]); 
 391         case WX_GL_MIN_ACCUM_BLUE
: 
 392           pfd
.cAccumBits 
+= (pfd
.cAccumBlueBits 
= attribList
[arg
++]); 
 394         case WX_GL_MIN_ACCUM_ALPHA
: 
 395           pfd
.cAccumBits 
+= (pfd
.cAccumAlphaBits 
= attribList
[arg
++]); 
 404 void wxGLCanvas::SetupPixelFormat(int *attribList
) // (HDC hDC) 
 407   PIXELFORMATDESCRIPTOR pfd 
= { 
 408         sizeof(PIXELFORMATDESCRIPTOR
),    /* size */ 
 412         PFD_DOUBLEBUFFER
,        /* support double-buffering */ 
 413         PFD_TYPE_RGBA
,            /* color type */ 
 414         16,                /* prefered color depth */ 
 415         0, 0, 0, 0, 0, 0,        /* color bits (ignored) */ 
 416         0,                /* no alpha buffer */ 
 417         0,                /* alpha bits (ignored) */ 
 418         0,                /* no accumulation buffer */ 
 419         0, 0, 0, 0,            /* accum bits (ignored) */ 
 420         16,                /* depth buffer */ 
 421         0,                /* no stencil buffer */ 
 422         0,                /* no auxiliary buffers */ 
 423         PFD_MAIN_PLANE
,            /* main layer */ 
 425         0, 0, 0,            /* no layer, visible, damage masks */ 
 428   AdjustPFDForAttributes(pfd
, attribList
); 
 430   pixelFormat 
= ChoosePixelFormat((HDC
) m_hDC
, &pfd
); 
 431   if (pixelFormat 
== 0) { 
 432     wxLogWarning(_("ChoosePixelFormat failed.")); 
 435     if (SetPixelFormat((HDC
) m_hDC
, pixelFormat
, &pfd
) != TRUE
) { 
 436       wxLogWarning(_("SetPixelFormat failed.")); 
 441 void wxGLCanvas::SetupPalette(const wxPalette
& palette
) 
 443     int pixelFormat 
= GetPixelFormat((HDC
) m_hDC
); 
 444     PIXELFORMATDESCRIPTOR pfd
; 
 446     DescribePixelFormat((HDC
) m_hDC
, pixelFormat
, sizeof(PIXELFORMATDESCRIPTOR
), &pfd
); 
 448     if (pfd
.dwFlags 
& PFD_NEED_PALETTE
) 
 458     if ( !m_palette
.Ok() ) 
 460         m_palette 
= CreateDefaultPalette(); 
 465         SelectPalette((HDC
) m_hDC
, (HPALETTE
) m_palette
.GetHPALETTE(), FALSE
); 
 466         RealizePalette((HDC
) m_hDC
); 
 470 wxPalette 
wxGLCanvas::CreateDefaultPalette() 
 472     PIXELFORMATDESCRIPTOR pfd
; 
 474     int pixelFormat 
= GetPixelFormat((HDC
) m_hDC
); 
 476     DescribePixelFormat((HDC
) m_hDC
, pixelFormat
, sizeof(PIXELFORMATDESCRIPTOR
), &pfd
); 
 478     paletteSize 
= 1 << pfd
.cColorBits
; 
 481      (LOGPALETTE
*) malloc(sizeof(LOGPALETTE
) + paletteSize 
* sizeof(PALETTEENTRY
)); 
 482     pPal
->palVersion 
= 0x300; 
 483     pPal
->palNumEntries 
= paletteSize
; 
 485     /* build a simple RGB color palette */ 
 487     int redMask 
= (1 << pfd
.cRedBits
) - 1; 
 488     int greenMask 
= (1 << pfd
.cGreenBits
) - 1; 
 489     int blueMask 
= (1 << pfd
.cBlueBits
) - 1; 
 492     for (i
=0; i
<paletteSize
; ++i
) { 
 493         pPal
->palPalEntry
[i
].peRed 
= 
 494             (((i 
>> pfd
.cRedShift
) & redMask
) * 255) / redMask
; 
 495         pPal
->palPalEntry
[i
].peGreen 
= 
 496             (((i 
>> pfd
.cGreenShift
) & greenMask
) * 255) / greenMask
; 
 497         pPal
->palPalEntry
[i
].peBlue 
= 
 498             (((i 
>> pfd
.cBlueShift
) & blueMask
) * 255) / blueMask
; 
 499         pPal
->palPalEntry
[i
].peFlags 
= 0; 
 503     HPALETTE hPalette 
= CreatePalette(pPal
); 
 507     palette
.SetHPALETTE((WXHPALETTE
) hPalette
); 
 512 void wxGLCanvas::SwapBuffers() 
 515     m_glContext
->SwapBuffers(); 
 518 void wxGLCanvas::OnSize(wxSizeEvent
& event
) 
 522 void wxGLCanvas::SetCurrent() 
 526     m_glContext
->SetCurrent(); 
 530 void wxGLCanvas::SetColour(const char *colour
) 
 533     m_glContext
->SetColour(colour
); 
 536 // TODO: Have to have this called by parent frame (?) 
 537 // So we need wxFrame to call OnQueryNewPalette for all children... 
 538 void wxGLCanvas::OnQueryNewPalette(wxQueryNewPaletteEvent
& event
) 
 540   /* realize palette if this is the current window */ 
 541   if ( GetPalette()->Ok() ) { 
 542     ::UnrealizeObject((HPALETTE
) GetPalette()->GetHPALETTE()); 
 543     ::SelectPalette((HDC
) GetHDC(), (HPALETTE
) GetPalette()->GetHPALETTE(), FALSE
); 
 544     ::RealizePalette((HDC
) GetHDC()); 
 546     event
.SetPaletteRealized(TRUE
); 
 549     event
.SetPaletteRealized(FALSE
); 
 552 // I think this doesn't have to be propagated to child windows. 
 553 void wxGLCanvas::OnPaletteChanged(wxPaletteChangedEvent
& event
) 
 555   /* realize palette if this is *not* the current window */ 
 557        GetPalette()->Ok() && (this != event
.GetChangedWindow()) ) 
 559     ::UnrealizeObject((HPALETTE
) GetPalette()->GetHPALETTE()); 
 560     ::SelectPalette((HDC
) GetHDC(), (HPALETTE
) GetPalette()->GetHPALETTE(), FALSE
); 
 561     ::RealizePalette((HDC
) GetHDC()); 
 566 /* Give extensions proper function names. */ 
 568 /* EXT_vertex_array */ 
 569 void glArrayElementEXT(GLint i
) 
 573 void glColorPointerEXT(GLint size
, GLenum type
, GLsizei stride
, GLsizei count
, const GLvoid 
*pointer
) 
 577 void glDrawArraysEXT(GLenum mode
, GLint first
, GLsizei count
) 
 579 #ifdef GL_EXT_vertex_array 
 580     static PFNGLDRAWARRAYSEXTPROC proc 
= 0; 
 584         proc 
= (PFNGLDRAWARRAYSEXTPROC
) wglGetProcAddress("glDrawArraysEXT"); 
 588         (* proc
) (mode
, first
, count
); 
 592 void glEdgeFlagPointerEXT(GLsizei stride
, GLsizei count
, const GLboolean 
*pointer
) 
 596 void glGetPointervEXT(GLenum pname
, GLvoid
* *params
) 
 600 void glIndexPointerEXT(GLenum type
, GLsizei stride
, GLsizei count
, const GLvoid 
*pointer
) 
 604 void glNormalPointerEXT(GLenum type
, GLsizei stride
, GLsizei count
, const GLvoid 
*pointer
) 
 606 #ifdef GL_EXT_vertex_array 
 607   static PFNGLNORMALPOINTEREXTPROC proc 
= 0; 
 611     proc 
= (PFNGLNORMALPOINTEREXTPROC
) wglGetProcAddress("glNormalPointerEXT"); 
 615     (* proc
) (type
, stride
, count
, pointer
); 
 619 void glTexCoordPointerEXT(GLint size
, GLenum type
, GLsizei stride
, GLsizei count
, const GLvoid 
*pointer
) 
 623 void glVertexPointerEXT(GLint size
, GLenum type
, GLsizei stride
, GLsizei count
, const GLvoid 
*pointer
) 
 625 #ifdef GL_EXT_vertex_array 
 626   static PFNGLVERTEXPOINTEREXTPROC proc 
= 0; 
 630     proc 
= (PFNGLVERTEXPOINTEREXTPROC
) wglGetProcAddress("glVertexPointerEXT"); 
 633     (* proc
) (size
, type
, stride
, count
, pointer
); 
 637 /* EXT_color_subtable */ 
 638 void glColorSubtableEXT(GLenum target
, GLsizei start
, GLsizei count
, GLenum format
, GLenum type
, const GLvoid 
*table
) 
 642 /* EXT_color_table */ 
 643 void glColorTableEXT(GLenum target
, GLenum internalformat
, GLsizei width
, GLenum format
, GLenum type
, const GLvoid 
*table
) 
 647 void glCopyColorTableEXT(GLenum target
, GLenum internalformat
, GLint x
, GLint y
, GLsizei width
) 
 651 void glGetColorTableEXT(GLenum target
, GLenum format
, GLenum type
, GLvoid 
*table
) 
 655 void glGetColorTableParamaterfvEXT(GLenum target
, GLenum pname
, GLfloat 
*params
) 
 659 void glGetColorTavleParameterivEXT(GLenum target
, GLenum pname
, GLint 
*params
) 
 663 /* SGI_compiled_vertex_array */ 
 664 void glLockArraysSGI(GLint first
, GLsizei count
) 
 668 void glUnlockArraysSGI() 
 673 /* SGI_cull_vertex */ 
 674 void glCullParameterdvSGI(GLenum pname
, GLdouble
* params
) 
 678 void glCullParameterfvSGI(GLenum pname
, GLfloat
* params
) 
 683 void glIndexFuncSGI(GLenum func
, GLclampf ref
) 
 687 /* SGI_index_material */ 
 688 void glIndexMaterialSGI(GLenum face
, GLenum mode
) 
 693 void glAddSwapHintRectWin(GLint x
, GLint y
, GLsizei width
, GLsizei height
) 
 698 //--------------------------------------------------------------------------- 
 700 //--------------------------------------------------------------------------- 
 702 IMPLEMENT_CLASS(wxGLApp
, wxApp
) 
 704 bool wxGLApp::InitGLVisual(int *attribList
) 
 707   PIXELFORMATDESCRIPTOR pfd 
= { 
 708         sizeof(PIXELFORMATDESCRIPTOR
),    /* size */ 
 712         PFD_DOUBLEBUFFER
,        /* support double-buffering */ 
 713         PFD_TYPE_RGBA
,            /* color type */ 
 714         16,                /* prefered color depth */ 
 715         0, 0, 0, 0, 0, 0,        /* color bits (ignored) */ 
 716         0,                /* no alpha buffer */ 
 717         0,                /* alpha bits (ignored) */ 
 718         0,                /* no accumulation buffer */ 
 719         0, 0, 0, 0,            /* accum bits (ignored) */ 
 720         16,                /* depth buffer */ 
 721         0,                /* no stencil buffer */ 
 722         0,                /* no auxiliary buffers */ 
 723         PFD_MAIN_PLANE
,            /* main layer */ 
 725         0, 0, 0,            /* no layer, visible, damage masks */ 
 728   AdjustPFDForAttributes(pfd
, attribList
); 
 730   // use DC for whole (root) screen, since no windows have yet been created 
 731   pixelFormat 
= ChoosePixelFormat((HDC
) ::GetDC(NULL
), &pfd
); 
 733   if (pixelFormat 
== 0) { 
 734     wxLogError(_("Failed to initialize OpenGL"));