Allow requesting core OpenGL profile and explicit OpenGL version.

Add WX_GL_CORE_PROFILE and WX_GL_{MAJOR,MINOR}_VERSION attributes which can be
used to use modern OpenGL with wxGLCanvas.

Closes #16402.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@77018 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/changes.txt

@@ -44,6 +44,7 @@ Unix:
 
 All (GUI):
 
+- Allow requesting modern (3.x+) OpenGL version in wxGLCanvas (Fabio Arnold).
 - XRC handler for wxAuiToolBar added (Kinaou Hervé, David Hart).
 - Add wxFD_NO_FOLLOW style for wxFileDialog (Luca Bacci).
 - Add support for embedding bitmaps in generated SVG in wxSVGFileDC (iwbnwif).

include/wx/glcanvas.h

@@ -48,7 +48,10 @@ enum
     WX_GL_MIN_ACCUM_BLUE,  // use blue buffer with most bits (> MIN_ACCUM_BLUE bits)
     WX_GL_MIN_ACCUM_ALPHA, // use alpha buffer with most bits (> MIN_ACCUM_ALPHA bits)
     WX_GL_SAMPLE_BUFFERS,  // 1 for multisampling support (antialiasing)
-    WX_GL_SAMPLES          // 4 for 2x2 antialiasing supersampling on most graphics cards
+    WX_GL_SAMPLES,         // 4 for 2x2 antialiasing supersampling on most graphics cards
+    WX_GL_CORE_PROFILE,    // use an OpenGL core profile
+    WX_GL_MAJOR_VERSION,   // major OpenGL version of the core profile
+    WX_GL_MINOR_VERSION    // minor OpenGL version of the core profile
 };
 
 #define wxGLCanvasName wxT("GLCanvas")

interface/wx/glcanvas.h

@@ -137,7 +137,44 @@ enum
     WX_GL_SAMPLE_BUFFERS,
 
     /// 4 for 2x2 antialiasing supersampling on most graphics cards
-    WX_GL_SAMPLES
+    WX_GL_SAMPLES,
+
+    /**
+        Request an OpenGL core profile.
+
+        Notice that using this attribute will result in also requesting OpenGL
+        at least version 3.0.
+
+        See ::WX_GL_MAJOR_VERSION and ::WX_GL_MINOR_VERSION for more precise
+        version selection.
+
+        @since 3.1.0
+     */
+    WX_GL_CORE_PROFILE,
+
+    /**
+        Request specific OpenGL core major version number (>= 3).
+
+        This attribute should be followed by the major version number
+        requested.
+
+        It has no effect under OS X where specifying ::WX_GL_CORE_PROFILE will
+        result in using OpenGL version at least 3.2 but can still be used
+        there for portability.
+
+        @since 3.1.0
+     */
+    WX_GL_MAJOR_VERSION,
+
+    /**
+        Request specific OpenGL core minor version number.
+
+        This attribute has the same semantics as ::WX_GL_MAJOR_VERSION but is
+        for the minor OpenGL version, e.g. 2 if OpenGL 3.2 is requested.
+
+        @since 3.1.0
+     */
+    WX_GL_MINOR_VERSION
 
 };
 

src/msw/glcanvas.cpp

@@ -45,7 +45,7 @@ LRESULT WXDLLEXPORT APIENTRY _EXPORT wxWndProc(HWND hWnd, UINT message,
 #endif
 
 // ----------------------------------------------------------------------------
-// define possibly missing WGL constants
+// define possibly missing WGL constants and types
 // ----------------------------------------------------------------------------
 
 #ifndef WGL_ARB_pixel_format
@@ -76,6 +76,49 @@ LRESULT WXDLLEXPORT APIENTRY _EXPORT wxWndProc(HWND hWnd, UINT message,
 #define WGL_SAMPLES_ARB                   0x2042
 #endif
 
+#ifndef WGL_ARB_create_context
+#define WGL_ARB_create_context
+#define WGL_CONTEXT_MAJOR_VERSION_ARB   0x2091
+#define WGL_CONTEXT_MINOR_VERSION_ARB   0x2092
+#define WGL_CONTEXT_LAYER_PLANE_ARB     0x2093
+#define WGL_CONTEXT_FLAGS_ARB           0x2094
+#define WGL_CONTEXT_DEBUG_BIT_ARB       0x0001
+#define WGL_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB  0x0002
+
+#ifndef WGL_ARB_create_context_profile
+#define WGL_ARB_create_context_profile
+#define WGL_CONTEXT_PROFILE_MASK_ARB              0x9126
+#define WGL_CONTEXT_CORE_PROFILE_BIT_ARB          0x00000001
+#define WGL_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB 0x00000002
+#endif
+
+#ifndef WGL_ARB_create_context_robustness
+#define WGL_ARB_create_context_robustness
+#define WGL_CONTEXT_ROBUST_ACCESS_BIT_ARB         0x00000004
+#define WGL_CONTEXT_RESET_NOTIFICATION_STRATEGY_ARB     0x8256
+#define WGL_NO_RESET_NOTIFICATION_ARB                   0x8261
+#define WGL_LOSE_CONTEXT_ON_RESET_ARB                   0x8252
+#endif
+#endif
+
+#ifndef WGL_EXT_create_context_es2_profile
+#define WGL_EXT_create_context_es2_profile
+#define WGL_CONTEXT_ES2_PROFILE_BIT_EXT           0x00000004
+#endif
+
+#ifndef WGL_EXT_create_context_es_profile
+#define WGL_EXT_create_context_es_profile
+#define WGL_CONTEXT_ES_PROFILE_BIT_EXT            0x00000004
+#endif
+
+#ifndef WGL_ARB_framebuffer_sRGB
+#define WGL_ARB_framebuffer_sRGB
+#define WGL_FRAMEBUFFER_SRGB_CAPABLE_ARB                0x20A9
+#endif
+
+typedef HGLRC(WINAPI * PFNWGLCREATECONTEXTATTRIBSARBPROC)
+    (HDC hDC, HGLRC hShareContext, const int *attribList);
+
 // ----------------------------------------------------------------------------
 // libraries
 // ----------------------------------------------------------------------------
@@ -108,10 +151,44 @@ LRESULT WXDLLEXPORT APIENTRY _EXPORT wxWndProc(HWND hWnd, UINT message,
 
 IMPLEMENT_CLASS(wxGLContext, wxObject)
 
+// The window will always be created first so the array will be initialized
+// and then the window will be assigned to the context.
+// max 8 attributes plus terminator
+// if first is 0, create legacy context
+static int s_wglContextAttribs[9] = {0};
+
 wxGLContext::wxGLContext(wxGLCanvas *win, const wxGLContext* other)
 {
-    m_glContext = wglCreateContext(win->GetHDC());
+    if ( s_wglContextAttribs[0] == 0 ) // create legacy context
-    wxCHECK_RET( m_glContext, wxT("Couldn't create OpenGL context") );
+    {
+        m_glContext = wglCreateContext(win->GetHDC());
+        wxCHECK_RET( m_glContext, wxT("Couldn't create OpenGL context") );
+    }
+    else // create a context using attributes
+    {
+        // We need to create a temporary context to get the
+        // wglCreateContextAttribsARB function
+        HGLRC tempContext = wglCreateContext(win->GetHDC());
+        wxCHECK_RET( tempContext, wxT("Couldn't create OpenGL context") );
+
+        wglMakeCurrent(win->GetHDC(), tempContext);
+        PFNWGLCREATECONTEXTATTRIBSARBPROC wglCreateContextAttribsARB
+            = (PFNWGLCREATECONTEXTATTRIBSARBPROC)
+            wglGetProcAddress("wglCreateContextAttribsARB");
+        wglMakeCurrent(win->GetHDC(), NULL);
+        wglDeleteContext(tempContext);
+
+        if ( !wglCreateContextAttribsARB )
+        {
+            wxLogError(_("Core OpenGL profile is not supported by the OpenGL driver."));
+            return;
+        }
+
+        m_glContext = wglCreateContextAttribsARB(
+            win->GetHDC(), 0, s_wglContextAttribs);
+        wxCHECK_RET( m_glContext,
+                     wxT("Couldn't create core profile OpenGL context") );
+    }
 
     if ( other )
     {
@@ -235,6 +312,55 @@ bool wxGLCanvas::Create(wxWindow *parent,
     if ( !CreateWindow(parent, id, pos, size, style, name) )
         return false;
 
+    // these will be used for the context creation attributes
+    // if a core profile is requested
+    bool useGLCoreProfile = false;
+
+    // the minimum gl core version is 3.0
+    int glVersionMajor = 3,
+        glVersionMinor = 0;
+
+    // Check for a core profile request
+    for ( int i = 0; attribList[i]; )
+    {
+        switch ( attribList[i++] )
+        {
+            case WX_GL_CORE_PROFILE:
+                useGLCoreProfile = true;
+                break;
+
+            case WX_GL_MAJOR_VERSION:
+                glVersionMajor = attribList[i++];
+                break;
+
+            case WX_GL_MINOR_VERSION:
+                glVersionMinor = attribList[i++];
+                break;
+
+            default:
+                // ignore all other flags for now
+                break;
+        }
+    }
+
+    if ( useGLCoreProfile )
+    {
+        s_wglContextAttribs[0] = WGL_CONTEXT_MAJOR_VERSION_ARB;
+        s_wglContextAttribs[1] = glVersionMajor;
+        s_wglContextAttribs[2] = WGL_CONTEXT_MINOR_VERSION_ARB;
+        s_wglContextAttribs[3] = glVersionMinor;
+        s_wglContextAttribs[4] = WGL_CONTEXT_FLAGS_ARB;
+        s_wglContextAttribs[5] = WGL_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB;
+        s_wglContextAttribs[6] = WGL_CONTEXT_PROFILE_MASK_ARB;
+        s_wglContextAttribs[7] = WGL_CONTEXT_CORE_PROFILE_BIT_ARB;
+        s_wglContextAttribs[8] = 0; // terminate
+    }
+    else // create legacy/compatibility context
+    {
+        s_wglContextAttribs[0] = 0;
+    }
+
+
     PIXELFORMATDESCRIPTOR pfd;
     const int setupVal = DoSetup(pfd, attribList);
     if ( setupVal == 0 ) // PixelFormat error

src/osx/cocoa/glcanvas.mm

@@ -213,6 +213,15 @@ WXGLPixelFormat WXGLChoosePixelFormat(const int *attribList)
                     data[p++] = NSOpenGLPFASamples;
                     data[p++] = (NSOpenGLPixelFormatAttribute) attribList[arg++];
                     break;
+
+                case WX_GL_CORE_PROFILE:
+                    data[p++] = NSOpenGLPFAOpenGLProfile;
+                    // request an OpenGL core profile
+                    // will use the highest available OpenGL version
+                    // which will be at least 3.2
+                    data[p++] = NSOpenGLProfileVersion3_2Core;
+
+                    break;
             }
         }
 

src/unix/glx11.cpp

@@ -36,15 +36,123 @@
     #endif
 #endif // __SGI__
 
+// ----------------------------------------------------------------------------
+// define possibly missing XGL constants and types
+// ----------------------------------------------------------------------------
+
+#ifndef GLX_NONE_EXT
+#define GLX_NONE_EXT                       0x8000
+#endif
+
+#ifndef GLX_ARB_multisample
+#define GLX_ARB_multisample
+#define GLX_SAMPLE_BUFFERS_ARB             100000
+#define GLX_SAMPLES_ARB                    100001
+#endif
+
+#ifndef GLX_EXT_visual_rating
+#define GLX_EXT_visual_rating
+#define GLX_VISUAL_CAVEAT_EXT              0x20
+#define GLX_NONE_EXT                       0x8000
+#define GLX_SLOW_VISUAL_EXT                0x8001
+#define GLX_NON_CONFORMANT_VISUAL_EXT      0x800D
+#endif
+
+#ifndef GLX_EXT_visual_info
+#define GLX_EXT_visual_info
+#define GLX_X_VISUAL_TYPE_EXT              0x22
+#define GLX_DIRECT_COLOR_EXT               0x8003
+#endif
+
+#ifndef GLX_ARB_create_context
+#define GLX_ARB_create_context
+#define GLX_CONTEXT_MAJOR_VERSION_ARB      0x2091
+#define GLX_CONTEXT_MINOR_VERSION_ARB      0x2092
+#define GLX_CONTEXT_FLAGS_ARB              0x2094
+#define GLX_CONTEXT_DEBUG_BIT_ARB          0x0001
+#define GLX_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB 0x0002
+
+/* Typedef for the GL 3.0 context creation function */
+typedef GLXContext(*PFNGLXCREATECONTEXTATTRIBSARBPROC)
+    (Display * dpy, GLXFBConfig config, GLXContext share_context,
+    Bool direct, const int *attrib_list);
+#endif
+
+#ifndef GLX_ARB_create_context_profile
+#define GLX_ARB_create_context_profile
+#define GLX_CONTEXT_PROFILE_MASK_ARB       0x9126
+#define GLX_CONTEXT_CORE_PROFILE_BIT_ARB   0x00000001
+#define GLX_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB 0x00000002
+#endif
+
+#ifndef GLX_ARB_create_context_robustness
+#define GLX_ARB_create_context_robustness
+#define GLX_CONTEXT_ROBUST_ACCESS_BIT_ARB  0x00000004
+#define GLX_CONTEXT_RESET_NOTIFICATION_STRATEGY_ARB     0x8256
+#define GLX_NO_RESET_NOTIFICATION_ARB                   0x8261
+#define GLX_LOSE_CONTEXT_ON_RESET_ARB                   0x8252
+#endif
+
+#ifndef GLX_EXT_create_context_es2_profile
+#define GLX_EXT_create_context_es2_profile
+#ifndef GLX_CONTEXT_ES2_PROFILE_BIT_EXT
+#define GLX_CONTEXT_ES2_PROFILE_BIT_EXT    0x00000002
+#endif
+#endif
+
+#ifndef GLX_ARB_framebuffer_sRGB
+#define GLX_ARB_framebuffer_sRGB
+#ifndef GLX_FRAMEBUFFER_SRGB_CAPABLE_ARB
+#define GLX_FRAMEBUFFER_SRGB_CAPABLE_ARB                0x20B2
+#endif
+#endif
+
+
 // ============================================================================
 // wxGLContext implementation
 // ============================================================================
 
 IMPLEMENT_CLASS(wxGLContext, wxObject)
 
+// The window will always be created first so the array will be initialized
+// and then the window will be assigned to the context.
+// max 8 attributes plus terminator
+// if first is 0, create legacy context
+static int s_glxContextAttribs[9] = {0};
+
 wxGLContext::wxGLContext(wxGLCanvas *gc, const wxGLContext *other)
 {
-    if ( wxGLCanvas::GetGLXVersion() >= 13 )
+    if ( s_glxContextAttribs[0] != 0 ) // OpenGL 3 context creation
+    {
+        XVisualInfo *vi = gc->GetXVisualInfo();
+        wxCHECK_RET( vi, wxT("invalid visual for OpenGL") );
+
+        // We need to create a temporary context to get the
+        // glXCreateContextAttribsARB function
+        GLXContext tempContext = glXCreateContext( wxGetX11Display(), vi,
+                                                   NULL,
+                                                   GL_TRUE );
+        wxCHECK_RET( tempContext, wxT("Couldn't create OpenGL context") );
+
+        PFNGLXCREATECONTEXTATTRIBSARBPROC glXCreateContextAttribsARB
+            = (PFNGLXCREATECONTEXTATTRIBSARBPROC)
+            glXGetProcAddress((GLubyte *)"glXCreateContextAttribsARB");
+        if ( !glXCreateContextAttribsARB )
+        {
+            wxLogError(_("Core OpenGL profile is not supported by the OpenGL driver."));
+            return;
+        }
+
+        GLXFBConfig *fbc = gc->GetGLXFBConfig();
+        wxCHECK_RET( fbc, wxT("invalid GLXFBConfig for OpenGL") );
+
+        m_glContext = glXCreateContextAttribsARB( wxGetX11Display(), fbc[0],
+            other ? other->m_glContext : None,
+            GL_TRUE, s_glxContextAttribs );
+
+        glXDestroyContext( wxGetX11Display(), tempContext );
+    }
+    else if ( wxGLCanvas::GetGLXVersion() >= 13 )
     {
         GLXFBConfig *fbc = gc->GetGLXFBConfig();
         wxCHECK_RET( fbc, wxT("invalid GLXFBConfig for OpenGL") );
@@ -170,6 +278,8 @@ wxGLCanvasX11::ConvertWXAttrsToGL(const int *wxattrs, int *glattrs, size_t n)
           old version but must be followed by True or False in the new one.
      */
 
+    s_glxContextAttribs[0] = 0; // default is legacy context
+
     if ( !wxattrs )
     {
         size_t i = 0;
@@ -199,6 +309,14 @@ wxGLCanvasX11::ConvertWXAttrsToGL(const int *wxattrs, int *glattrs, size_t n)
     }
     else // have non-default attributes
     {
+        // these will be used for the context creation attributes
+        // if a core profile is requested
+        bool useGLCoreProfile = false;
+
+        // the minimum gl core version is 3.0
+        int glVersionMajor = 3,
+            glVersionMinor = 0;
+
         size_t p = 0;
         for ( int arg = 0; wxattrs[arg] != 0; )
         {
@@ -315,6 +433,18 @@ wxGLCanvasX11::ConvertWXAttrsToGL(const int *wxattrs, int *glattrs, size_t n)
 
                     return false;
 
+                case WX_GL_CORE_PROFILE:
+                    useGLCoreProfile = true;
+                    continue;
+
+                case WX_GL_MAJOR_VERSION:
+                    glVersionMajor = wxattrs[arg++];
+                    continue;
+
+                case WX_GL_MINOR_VERSION:
+                    glVersionMinor = wxattrs[arg++];
+                    continue;
+
                 default:
                     wxLogDebug(wxT("Unsupported OpenGL attribute %d"),
                                wxattrs[arg - 1]);
@@ -336,6 +466,23 @@ wxGLCanvasX11::ConvertWXAttrsToGL(const int *wxattrs, int *glattrs, size_t n)
         }
 
         glattrs[p] = None;
+
+        if ( useGLCoreProfile )
+        {
+            s_glxContextAttribs[0] = GLX_CONTEXT_MAJOR_VERSION_ARB;
+            s_glxContextAttribs[1] = glVersionMajor;
+            s_glxContextAttribs[2] = GLX_CONTEXT_MINOR_VERSION_ARB;
+            s_glxContextAttribs[3] = glVersionMinor;
+            s_glxContextAttribs[4] = GLX_CONTEXT_FLAGS_ARB;
+            s_glxContextAttribs[5] = GLX_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB;
+            s_glxContextAttribs[6] = GLX_CONTEXT_PROFILE_MASK_ARB;
+            s_glxContextAttribs[7] = GLX_CONTEXT_CORE_PROFILE_BIT_ARB;
+            s_glxContextAttribs[8] = 0; // terminate
+        }
+        else // create legacy/compatibility context
+        {
+            s_glxContextAttribs[0] = 0;
+        }
     }
 
     return true;