[wxWidgets.git] / src / x11 / glcanvas.cpp

/////////////////////////////////////////////////////////////////////////////
// Name:        glcanvas.cpp
// Purpose:     wxGLCanvas, for using OpenGL with wxWindows 2.0 for Motif.
//              Uses the GLX extension.
// Author:      Julian Smart and Wolfram Gloger
// Modified by:
// Created:     1995, 1999
// RCS-ID:      $Id$
// Copyright:   (c) Julian Smart, Wolfram Gloger
// Licence:   	wxWindows licence
/////////////////////////////////////////////////////////////////////////////

#ifdef __GNUG__
#pragma implementation "glcanvas.h"
#endif

#include "wx/setup.h"

#if wxUSE_GLCANVAS

#include "wx/glcanvas.h"
#include "wx/utils.h"
#include "wx/app.h"

#ifdef __VMS
# pragma message disable nosimpint
#endif
#include <Xm/Xm.h>
#ifdef __VMS
# pragma message enable nosimpint
#endif
#include "wx/motif/private.h"

#ifdef OLD_MESA
// workaround for bug in Mesa's glx.c
static int bitcount( unsigned long n )
{
    int bits;
    for (bits=0; n>0;) {
	if(n & 1) bits++;
	n = n >> 1;
    }
    return bits;
}
#endif

/*
 * GLContext implementation
 */

IMPLEMENT_CLASS(wxGLContext,wxObject)

wxGLContext::wxGLContext( bool WXUNUSED(isRGB), wxWindow *win, 
                          const wxPalette& WXUNUSED(palette) )
{
    m_window = win;
    // m_widget = win->m_wxwindow;

    wxGLCanvas *gc = (wxGLCanvas*) win;
    XVisualInfo *vi = (XVisualInfo *) gc->m_vi;
    
    wxCHECK_RET( vi, "invalid visual for OpenGl" );
    
    m_glContext = glXCreateContext( (Display *)m_window->GetXDisplay(), vi,
                                    None, GL_TRUE);
  
    wxCHECK_RET( m_glContext, "Couldn't create OpenGl context" );
}

wxGLContext::wxGLContext( 
               bool WXUNUSED(isRGB), wxWindow *win, 
               const wxPalette& WXUNUSED(palette),
               const wxGLContext *other        /* for sharing display lists */
)
{
    m_window = win;
    // m_widget = win->m_wxwindow;

    wxGLCanvas *gc = (wxGLCanvas*) win;
    XVisualInfo *vi = (XVisualInfo *) gc->m_vi;
    
    wxCHECK_RET( vi, "invalid visual for OpenGl" );
    
    if( other != 0 )
        m_glContext = glXCreateContext( (Display *)m_window->GetXDisplay(), vi, 
                                        other->m_glContext, GL_TRUE );
    else
        m_glContext = glXCreateContext( (Display *)m_window->GetXDisplay(), vi,
                                        None, GL_TRUE );
    
    wxCHECK_RET( m_glContext, "Couldn't create OpenGl context" );
}

wxGLContext::~wxGLContext()
{
    if (!m_glContext) return;
    
    if (m_glContext == glXGetCurrentContext())
    {
        glXMakeCurrent( (Display*) m_window->GetXDisplay(), None, NULL);
    }
	
    glXDestroyContext( (Display*) m_window->GetXDisplay(), m_glContext );
}

void wxGLContext::SwapBuffers()
{
    if (m_glContext)
    {
        Display* display = (Display*) m_window->GetXDisplay();
        glXSwapBuffers(display, (Window) m_window->GetXWindow());
    }
}

void wxGLContext::SetCurrent()
{
    if (m_glContext) 
    { 
        Display* display = (Display*) m_window->GetXDisplay();
        glXMakeCurrent(display, (Window) m_window->GetXWindow(), 
                       m_glContext );;
    }
}

void wxGLContext::SetColour(const char *colour)
{
    wxColour *the_colour = wxTheColourDatabase->FindColour(colour);
    if(the_colour) {
	GLboolean b;
	glGetBooleanv(GL_RGBA_MODE, &b);
	if(b) {
	    glColor3ub(the_colour->Red(),
		       the_colour->Green(),
		       the_colour->Blue());
	} else {
            the_colour->CalcPixel(wxTheApp->GetMainColormap(m_window->GetXDisplay()));
	    GLint pix = (GLint)the_colour->GetPixel();
	    if(pix == -1)
            {
                wxLogError("wxGLCanvas: cannot allocate color\n");
		return;
            }
	    glIndexi(pix);
	}
    }
}

void wxGLContext::SetupPixelFormat()
{
}

void wxGLContext::SetupPalette( const wxPalette& WXUNUSED(palette) )
{
}

wxPalette wxGLContext::CreateDefaultPalette()
{
    return wxNullPalette;
}


/*
 * GLCanvas implementation
 */

IMPLEMENT_CLASS(wxGLCanvas, wxScrolledWindow)

BEGIN_EVENT_TABLE(wxGLCanvas, wxScrolledWindow)
//    EVT_SIZE(wxGLCanvas::OnSize)
END_EVENT_TABLE()


wxGLCanvas::wxGLCanvas( wxWindow *parent, wxWindowID id,
                        const wxPoint& pos, const wxSize& size, 
			long style, const wxString& name,
                        int *attribList, 
			const wxPalette& palette )
: wxScrolledWindow(parent, id, pos, size, style, name)
{
    Create( parent, NULL, NULL, id, pos, size, style, name, attribList, palette );
}

wxGLCanvas::wxGLCanvas( wxWindow *parent, 
                        const wxGLContext *shared,
                        wxWindowID id,
                        const wxPoint& pos, const wxSize& size, 
			long style, const wxString& name,
                        int *attribList, 
			const wxPalette& palette )
: wxScrolledWindow(parent, id, pos, size, style, name)
{			
    Create( parent, shared, NULL, id, pos, size, style, name, attribList, palette );
}

wxGLCanvas::wxGLCanvas( wxWindow *parent, 
                        const wxGLCanvas *shared,
                        wxWindowID id,
                        const wxPoint& pos, const wxSize& size, 
			long style, const wxString& name,
                        int *attribList, 
			const wxPalette& palette )
: wxScrolledWindow(parent, id, pos, size, style, name)
{			
    Create( parent, NULL, shared, id, pos, size, style, name, attribList, palette );
}


/*
bool wxGLCanvas::Create(wxWindow *parent,
  const wxGLContext *shared, const wxGLCanvas *shared_context_of,
  wxWindowID id = -1, const wxPoint& pos,
  const wxSize& size, long style, 
  const wxString& name, int *attribList, const wxPalette& palette):
    wxScrolledWindow(parent, id, pos, size, style, name)
*/

bool wxGLCanvas::Create( wxWindow *parent, 
                         const wxGLContext *shared,
                         const wxGLCanvas *shared_context_of,
                         wxWindowID id,
                         const wxPoint& pos, const wxSize& size, 
			 long style, const wxString& name,
                         int *attribList, 
			 const wxPalette& palette)
{
    XVisualInfo *vi, vi_templ;
    XWindowAttributes xwa;
    int val, n;

    m_sharedContext = (wxGLContext*)shared;  // const_cast
    m_sharedContextOf = (wxGLCanvas*)shared_context_of;  // const_cast
    m_glContext = (wxGLContext*) NULL;

    Display* display = (Display*) GetXDisplay();

    // Check for the presence of the GLX extension
    if(!glXQueryExtension(display, NULL, NULL)) {
	wxDebugMsg("wxGLCanvas: GLX extension is missing\n");
	return false;
    }

    if(attribList) {
      int data[512], arg=0, p=0;
       
      while( (attribList[arg]!=0) && (p<512) )
      {
        switch( attribList[arg++] )
        {
          case WX_GL_RGBA: data[p++] = GLX_RGBA; break;
          case WX_GL_BUFFER_SIZE:
            data[p++]=GLX_BUFFER_SIZE; data[p++]=attribList[arg++]; break;
          case WX_GL_LEVEL:
            data[p++]=GLX_LEVEL; data[p++]=attribList[arg++]; break;
          case WX_GL_DOUBLEBUFFER: data[p++] = GLX_DOUBLEBUFFER; break;
          case WX_GL_STEREO: data[p++] = GLX_STEREO; break;
          case WX_GL_AUX_BUFFERS:
            data[p++]=GLX_AUX_BUFFERS; data[p++]=attribList[arg++]; break;
          case WX_GL_MIN_RED:
            data[p++]=GLX_RED_SIZE; data[p++]=attribList[arg++]; break;
          case WX_GL_MIN_GREEN:
            data[p++]=GLX_GREEN_SIZE; data[p++]=attribList[arg++]; break;
          case WX_GL_MIN_BLUE:
            data[p++]=GLX_BLUE_SIZE; data[p++]=attribList[arg++]; break;
          case WX_GL_MIN_ALPHA:
            data[p++]=GLX_ALPHA_SIZE; data[p++]=attribList[arg++]; break;
          case WX_GL_DEPTH_SIZE: 
            data[p++]=GLX_DEPTH_SIZE; data[p++]=attribList[arg++]; break;
          case WX_GL_STENCIL_SIZE: 
            data[p++]=GLX_STENCIL_SIZE; data[p++]=attribList[arg++]; break;
          case WX_GL_MIN_ACCUM_RED:
            data[p++]=GLX_ACCUM_RED_SIZE; data[p++]=attribList[arg++]; break;
          case WX_GL_MIN_ACCUM_GREEN:
            data[p++]=GLX_ACCUM_GREEN_SIZE; data[p++]=attribList[arg++]; break;
          case WX_GL_MIN_ACCUM_BLUE:
            data[p++]=GLX_ACCUM_BLUE_SIZE; data[p++]=attribList[arg++]; break;
          case WX_GL_MIN_ACCUM_ALPHA:
            data[p++]=GLX_ACCUM_ALPHA_SIZE; data[p++]=attribList[arg++]; break;
          default:
            break;
        }
      }       
      data[p] = 0; 

      attribList = (int*) data;
      // Get an appropriate visual
      vi = glXChooseVisual(display, DefaultScreen(display), attribList);
      if(!vi) return false;
      
      // Here we should make sure that vi is the same visual as the
      // one used by the xwindow drawable in wxCanvas.  However,
      // there is currently no mechanism for this in wx_canvs.cc.
    } else {
	// By default, we use the visual of xwindow
        // NI: is this really senseful ? opengl in e.g. color index mode ?
	XGetWindowAttributes(display, (Window) GetXWindow(), &xwa);
	vi_templ.visualid = XVisualIDFromVisual(xwa.visual);
	vi = XGetVisualInfo(display, VisualIDMask, &vi_templ, &n);
	if(!vi) return false;
	glXGetConfig(display, vi, GLX_USE_GL, &val);
	if(!val) return false;
	// Basically, this is it.  It should be possible to use vi
	// in glXCreateContext() below.  But this fails with Mesa.
	// I notified the Mesa author about it; there may be a fix.
#ifdef OLD_MESA
	// Construct an attribute list matching the visual
	int a_list[32];
	n = 0;
	if(vi->c_class==TrueColor || vi->c_class==DirectColor) { // RGBA visual
	    a_list[n++] = GLX_RGBA;
	    a_list[n++] = GLX_RED_SIZE;
	    a_list[n++] = bitcount(vi->red_mask);
	    a_list[n++] = GLX_GREEN_SIZE;
	    a_list[n++] = bitcount(vi->green_mask);
	    a_list[n++] = GLX_BLUE_SIZE;
	    a_list[n++] = bitcount(vi->blue_mask);
	    glXGetConfig(display, vi, GLX_ALPHA_SIZE, &val);
	    a_list[n++] = GLX_ALPHA_SIZE;
	    a_list[n++] = val;
	} else { // Color index visual
	    glXGetConfig(display, vi, GLX_BUFFER_SIZE, &val);
	    a_list[n++] = GLX_BUFFER_SIZE;
	    a_list[n++] = val;
	}
	a_list[n] = None;
	// XFree(vi);
	vi = glXChooseVisual(display, DefaultScreen(display), a_list);
	if(!vi) return false;
#endif /* OLD_MESA */
    }

    m_vi = vi;  // safe for later use
    
    wxCHECK_MSG( m_vi, FALSE, "required visual couldn't be found" );

    // Create the GLX context and make it current

    wxGLContext *share= m_sharedContext;
    if (share==NULL && m_sharedContextOf) 
        share = m_sharedContextOf->GetContext();

    m_glContext = new wxGLContext( TRUE, this, wxNullPalette, share );

#ifndef OLD_MESA
    // XFree(vi);
#endif
    SetCurrent();

    return true;
}

wxGLCanvas::~wxGLCanvas(void)
{
    XVisualInfo *vi = (XVisualInfo *) m_vi;
    
    if (vi) XFree( vi );
    if (m_glContext) delete m_glContext;

    // Display* display = (Display*) GetXDisplay();
    // if(glx_cx) glXDestroyContext(display, glx_cx);
}

void wxGLCanvas::SwapBuffers()
{
    if( m_glContext ) m_glContext->SwapBuffers();

    // Display* display = (Display*) GetXDisplay();
    // if(glx_cx) glXSwapBuffers(display, (Window) GetXWindow());
}

void wxGLCanvas::SetCurrent()
{
    if( m_glContext ) m_glContext->SetCurrent();

    // Display* display = (Display*) GetXDisplay();
    // if(glx_cx) glXMakeCurrent(display, (Window) GetXWindow(), glx_cx);
}

void wxGLCanvas::SetColour(const char *col)
{
    if( m_glContext ) m_glContext->SetColour(col);
}

#endif
    // wxUSE_GLCANVAS
Commit	Line	Data
83df96d6 JS	1	/////////////////////////////////////////////////////////////////////////////
	2	// Name: glcanvas.cpp
	3	// Purpose: wxGLCanvas, for using OpenGL with wxWindows 2.0 for Motif.
	4	// Uses the GLX extension.
	5	// Author: Julian Smart and Wolfram Gloger
	6	// Modified by:
	7	// Created: 1995, 1999
	8	// RCS-ID: $Id$
	9	// Copyright: (c) Julian Smart, Wolfram Gloger
	10	// Licence: wxWindows licence
	11	/////////////////////////////////////////////////////////////////////////////
	12
	13	#ifdef __GNUG__
	14	#pragma implementation "glcanvas.h"
	15	#endif
	16
	17	#include "wx/setup.h"
	18
	19	#if wxUSE_GLCANVAS
	20
	21	#include "wx/glcanvas.h"
	22	#include "wx/utils.h"
	23	#include "wx/app.h"
	24
	25	#ifdef __VMS
	26	# pragma message disable nosimpint
	27	#endif
	28	#include <Xm/Xm.h>
	29	#ifdef __VMS
	30	# pragma message enable nosimpint
	31	#endif
	32	#include "wx/motif/private.h"
	33
	34	#ifdef OLD_MESA
	35	// workaround for bug in Mesa's glx.c
	36	static int bitcount( unsigned long n )
	37	{
	38	int bits;
	39	for (bits=0; n>0;) {
	40	if(n & 1) bits++;
	41	n = n >> 1;
	42	}
	43	return bits;
	44	}
	45	#endif
	46
	47	/*
	48	* GLContext implementation
	49	*/
	50
	51	IMPLEMENT_CLASS(wxGLContext,wxObject)
	52
	53	wxGLContext::wxGLContext( bool WXUNUSED(isRGB), wxWindow *win,
	54	const wxPalette& WXUNUSED(palette) )
	55	{
	56	m_window = win;
	57	// m_widget = win->m_wxwindow;
	58
	59	wxGLCanvas gc = (wxGLCanvas) win;
	60	XVisualInfo vi = (XVisualInfo ) gc->m_vi;
	61
	62	wxCHECK_RET( vi, "invalid visual for OpenGl" );
	63
	64	m_glContext = glXCreateContext( (Display *)m_window->GetXDisplay(), vi,
65	None, GL_TRUE);
66
67	wxCHECK_RET( m_glContext, "Couldn't create OpenGl context" );
68	}
69
70	wxGLContext::wxGLContext(
71	bool WXUNUSED(isRGB), wxWindow *win,
72	const wxPalette& WXUNUSED(palette),
73	const wxGLContext other / for sharing display lists */
74	)
75	{
76	m_window = win;
77	// m_widget = win->m_wxwindow;
78
79	wxGLCanvas gc = (wxGLCanvas) win;
80	XVisualInfo vi = (XVisualInfo ) gc->m_vi;
81
82	wxCHECK_RET( vi, "invalid visual for OpenGl" );
83
84	if( other != 0 )
85	m_glContext = glXCreateContext( (Display *)m_window->GetXDisplay(), vi,
86	other->m_glContext, GL_TRUE );
87	else
88	m_glContext = glXCreateContext( (Display *)m_window->GetXDisplay(), vi,
89	None, GL_TRUE );
90
91	wxCHECK_RET( m_glContext, "Couldn't create OpenGl context" );
92	}
93
94	wxGLContext::~wxGLContext()
95	{
96	if (!m_glContext) return;
97
98	if (m_glContext == glXGetCurrentContext())
99	{
100	glXMakeCurrent( (Display*) m_window->GetXDisplay(), None, NULL);
101	}
102
103	glXDestroyContext( (Display*) m_window->GetXDisplay(), m_glContext );
104	}
105
106	void wxGLContext::SwapBuffers()
107	{
108	if (m_glContext)
109	{
110	Display* display = (Display*) m_window->GetXDisplay();
111	glXSwapBuffers(display, (Window) m_window->GetXWindow());
112	}
113	}
114
115	void wxGLContext::SetCurrent()
116	{
117	if (m_glContext)
118	{
119	Display* display = (Display*) m_window->GetXDisplay();
120	glXMakeCurrent(display, (Window) m_window->GetXWindow(),
121	m_glContext );;
122	}
123	}
124
125	void wxGLContext::SetColour(const char *colour)
126	{
127	wxColour *the_colour = wxTheColourDatabase->FindColour(colour);
128	if(the_colour) {
129	GLboolean b;
130	glGetBooleanv(GL_RGBA_MODE, &b);
131	if(b) {
132	glColor3ub(the_colour->Red(),
133	the_colour->Green(),
134	the_colour->Blue());
135	} else {
e3baff1c JS	136	the_colour->CalcPixel(wxTheApp->GetMainColormap(m_window->GetXDisplay()));
	137	GLint pix = (GLint)the_colour->GetPixel();
	138	if(pix == -1)
	139	{
	140	wxLogError("wxGLCanvas: cannot allocate color\n");
	141	return;
	142	}
83df96d6 JS	143	glIndexi(pix);
	144	}
	145	}
	146	}
	147
	148	void wxGLContext::SetupPixelFormat()
	149	{
	150	}
	151
	152	void wxGLContext::SetupPalette( const wxPalette& WXUNUSED(palette) )
	153	{
	154	}
	155
	156	wxPalette wxGLContext::CreateDefaultPalette()
	157	{
	158	return wxNullPalette;
	159	}
	160
	161
	162
	163
	164	/*
	165	* GLCanvas implementation
	166	*/
	167
	168	IMPLEMENT_CLASS(wxGLCanvas, wxScrolledWindow)
	169
	170	BEGIN_EVENT_TABLE(wxGLCanvas, wxScrolledWindow)
	171	// EVT_SIZE(wxGLCanvas::OnSize)
	172	END_EVENT_TABLE()
	173
	174
	175	wxGLCanvas::wxGLCanvas( wxWindow *parent, wxWindowID id,
	176	const wxPoint& pos, const wxSize& size,
	177	long style, const wxString& name,
	178	int *attribList,
	179	const wxPalette& palette )
	180	: wxScrolledWindow(parent, id, pos, size, style, name)
	181	{
	182	Create( parent, NULL, NULL, id, pos, size, style, name, attribList, palette );
	183	}
	184
	185	wxGLCanvas::wxGLCanvas( wxWindow *parent,
	186	const wxGLContext *shared,
	187	wxWindowID id,
	188	const wxPoint& pos, const wxSize& size,
	189	long style, const wxString& name,
	190	int *attribList,
	191	const wxPalette& palette )
	192	: wxScrolledWindow(parent, id, pos, size, style, name)
	193	{
	194	Create( parent, shared, NULL, id, pos, size, style, name, attribList, palette );
	195	}
	196
	197	wxGLCanvas::wxGLCanvas( wxWindow *parent,
	198	const wxGLCanvas *shared,
	199	wxWindowID id,
	200	const wxPoint& pos, const wxSize& size,
	201	long style, const wxString& name,
	202	int *attribList,
	203	const wxPalette& palette )
	204	: wxScrolledWindow(parent, id, pos, size, style, name)
	205	{
	206	Create( parent, NULL, shared, id, pos, size, style, name, attribList, palette );
207	}
208
209
210	/*
211	bool wxGLCanvas::Create(wxWindow *parent,
212	const wxGLContext shared, const wxGLCanvas shared_context_of,
213	wxWindowID id = -1, const wxPoint& pos,
214	const wxSize& size, long style,
215	const wxString& name, int *attribList, const wxPalette& palette):
216	wxScrolledWindow(parent, id, pos, size, style, name)
217	*/
218
219	bool wxGLCanvas::Create( wxWindow *parent,
220	const wxGLContext *shared,
221	const wxGLCanvas *shared_context_of,
222	wxWindowID id,
223	const wxPoint& pos, const wxSize& size,
224	long style, const wxString& name,
225	int *attribList,
226	const wxPalette& palette)
227	{
228	XVisualInfo *vi, vi_templ;
229	XWindowAttributes xwa;
230	int val, n;
231
232	m_sharedContext = (wxGLContext*)shared; // const_cast
233	m_sharedContextOf = (wxGLCanvas*)shared_context_of; // const_cast
234	m_glContext = (wxGLContext*) NULL;
235
236	Display* display = (Display*) GetXDisplay();
237
238	// Check for the presence of the GLX extension
239	if(!glXQueryExtension(display, NULL, NULL)) {
240	wxDebugMsg("wxGLCanvas: GLX extension is missing\n");
241	return false;
242	}
243
244	if(attribList) {
245	int data[512], arg=0, p=0;
246
247	while( (attribList[arg]!=0) && (p<512) )
248	{
249	switch( attribList[arg++] )
250	{
251	case WX_GL_RGBA: data[p++] = GLX_RGBA; break;
252	case WX_GL_BUFFER_SIZE:
253	data[p++]=GLX_BUFFER_SIZE; data[p++]=attribList[arg++]; break;
254	case WX_GL_LEVEL:
255	data[p++]=GLX_LEVEL; data[p++]=attribList[arg++]; break;
256	case WX_GL_DOUBLEBUFFER: data[p++] = GLX_DOUBLEBUFFER; break;
257	case WX_GL_STEREO: data[p++] = GLX_STEREO; break;
258	case WX_GL_AUX_BUFFERS:
259	data[p++]=GLX_AUX_BUFFERS; data[p++]=attribList[arg++]; break;
260	case WX_GL_MIN_RED:
261	data[p++]=GLX_RED_SIZE; data[p++]=attribList[arg++]; break;
262	case WX_GL_MIN_GREEN:
263	data[p++]=GLX_GREEN_SIZE; data[p++]=attribList[arg++]; break;
264	case WX_GL_MIN_BLUE:
265	data[p++]=GLX_BLUE_SIZE; data[p++]=attribList[arg++]; break;
266	case WX_GL_MIN_ALPHA:
267	data[p++]=GLX_ALPHA_SIZE; data[p++]=attribList[arg++]; break;
268	case WX_GL_DEPTH_SIZE:
269	data[p++]=GLX_DEPTH_SIZE; data[p++]=attribList[arg++]; break;
270	case WX_GL_STENCIL_SIZE:
271	data[p++]=GLX_STENCIL_SIZE; data[p++]=attribList[arg++]; break;
272	case WX_GL_MIN_ACCUM_RED:
273	data[p++]=GLX_ACCUM_RED_SIZE; data[p++]=attribList[arg++]; break;
274	case WX_GL_MIN_ACCUM_GREEN:
275	data[p++]=GLX_ACCUM_GREEN_SIZE; data[p++]=attribList[arg++]; break;
276	case WX_GL_MIN_ACCUM_BLUE:
277	data[p++]=GLX_ACCUM_BLUE_SIZE; data[p++]=attribList[arg++]; break;
278	case WX_GL_MIN_ACCUM_ALPHA:
279	data[p++]=GLX_ACCUM_ALPHA_SIZE; data[p++]=attribList[arg++]; break;
280	default:
281	break;
282	}
283	}
284	data[p] = 0;
285
286	attribList = (int*) data;
287	// Get an appropriate visual
288	vi = glXChooseVisual(display, DefaultScreen(display), attribList);
289	if(!vi) return false;
290
291	// Here we should make sure that vi is the same visual as the
292	// one used by the xwindow drawable in wxCanvas. However,
293	// there is currently no mechanism for this in wx_canvs.cc.
294	} else {
295	// By default, we use the visual of xwindow
296	// NI: is this really senseful ? opengl in e.g. color index mode ?
297	XGetWindowAttributes(display, (Window) GetXWindow(), &xwa);
298	vi_templ.visualid = XVisualIDFromVisual(xwa.visual);
299	vi = XGetVisualInfo(display, VisualIDMask, &vi_templ, &n);
300	if(!vi) return false;
301	glXGetConfig(display, vi, GLX_USE_GL, &val);
302	if(!val) return false;
303	// Basically, this is it. It should be possible to use vi
304	// in glXCreateContext() below. But this fails with Mesa.
305	// I notified the Mesa author about it; there may be a fix.
306	#ifdef OLD_MESA
307	// Construct an attribute list matching the visual
308	int a_list[32];
309	n = 0;
310	if(vi->c_class==TrueColor \|\| vi->c_class==DirectColor) { // RGBA visual
311	a_list[n++] = GLX_RGBA;
312	a_list[n++] = GLX_RED_SIZE;
313	a_list[n++] = bitcount(vi->red_mask);
314	a_list[n++] = GLX_GREEN_SIZE;
315	a_list[n++] = bitcount(vi->green_mask);
316	a_list[n++] = GLX_BLUE_SIZE;
317	a_list[n++] = bitcount(vi->blue_mask);
318	glXGetConfig(display, vi, GLX_ALPHA_SIZE, &val);
319	a_list[n++] = GLX_ALPHA_SIZE;
320	a_list[n++] = val;
321	} else { // Color index visual
322	glXGetConfig(display, vi, GLX_BUFFER_SIZE, &val);
323	a_list[n++] = GLX_BUFFER_SIZE;
324	a_list[n++] = val;
325	}
326	a_list[n] = None;
327	// XFree(vi);
328	vi = glXChooseVisual(display, DefaultScreen(display), a_list);
329	if(!vi) return false;
330	#endif /* OLD_MESA */
331	}
332
333	m_vi = vi; // safe for later use
334
335	wxCHECK_MSG( m_vi, FALSE, "required visual couldn't be found" );
336
337	// Create the GLX context and make it current
338
339	wxGLContext *share= m_sharedContext;
340	if (share==NULL && m_sharedContextOf)
341	share = m_sharedContextOf->GetContext();
342
343	m_glContext = new wxGLContext( TRUE, this, wxNullPalette, share );
344
345	#ifndef OLD_MESA
346	// XFree(vi);
347	#endif
348	SetCurrent();
349
350	return true;
351	}
352
353	wxGLCanvas::~wxGLCanvas(void)
354	{
355	XVisualInfo vi = (XVisualInfo ) m_vi;
356
357	if (vi) XFree( vi );
358	if (m_glContext) delete m_glContext;
359
360	// Display* display = (Display*) GetXDisplay();
361	// if(glx_cx) glXDestroyContext(display, glx_cx);
362	}
363
364	void wxGLCanvas::SwapBuffers()
365	{
366	if( m_glContext ) m_glContext->SwapBuffers();
367
368	// Display* display = (Display*) GetXDisplay();
369	// if(glx_cx) glXSwapBuffers(display, (Window) GetXWindow());
370	}
371
372	void wxGLCanvas::SetCurrent()
373	{
374	if( m_glContext ) m_glContext->SetCurrent();
375
376	// Display* display = (Display*) GetXDisplay();
377	// if(glx_cx) glXMakeCurrent(display, (Window) GetXWindow(), glx_cx);
378	}
379
380	void wxGLCanvas::SetColour(const char *col)
381	{
382	if( m_glContext ) m_glContext->SetColour(col);
383	}
384
385	#endif
386	// wxUSE_GLCANVAS
387