龙芯系统下，GTK与OPENGL共舞

龙芯操作系统下，GTK的版本是3.14，并不支持直接与OPENGL互操作。

查询了一些资料，在GtkDrawingArea上画出简单的OPENGL图形。

首先基于gtk的网站demo，链接如下：

https://wiki.gnome.org/Projects/Vala/OpenGLSamples

Using GLX: Coloured Triangle

原始vala代码如下：

using Gtk;
using Gdk;
using GLX;
using GL;

class GLXSample : Gtk.Window {

    private X.Display xdisplay;
    private GLX.Context context;
    private XVisualInfo xvinfo;

    public GLXSample () {
        this.title = "OpenGL with GLX";
        set_reallocate_redraws (true);
        destroy.connect (Gtk.main_quit);

        int[] attrlist = {
            GLX_RGBA,
            GLX_RED_SIZE, 1,
            GLX_GREEN_SIZE, 1,
            GLX_BLUE_SIZE, 1,
            GLX_DOUBLEBUFFER, 0
        };

        this.xdisplay = x11_get_default_xdisplay ();
        if (!glXQueryExtension (xdisplay, null, null)) {
            stderr.printf ("OpenGL not supported
");
        }

        this.xvinfo = glXChooseVisual (xdisplay, x11_get_default_screen (), attrlist);
        if (xvinfo == null) {
            stderr.printf ("Error configuring OpenGL
");
        }

        var drawing_area = new DrawingArea ();
        drawing_area.set_size_request (300, 300);
        drawing_area.set_double_buffered (false);

        this.context = glXCreateContext (xdisplay, xvinfo, null, true);

        drawing_area.configure_event.connect (on_configure_event);
        drawing_area.expose_event.connect (on_expose_event);

        add (drawing_area);
    }

    private bool on_configure_event (Widget widget, Gdk.EventConfigure event) {
        if (!glXMakeCurrent (xdisplay, x11_drawable_get_xid (widget.window), context))
            return false;

        glViewport (0, 0, (GLsizei) widget.allocation.width,
                          (GLsizei) widget.allocation.height);

        return true;
    }

    private bool on_expose_event (Widget widget, Gdk.EventExpose event) {
        if (!glXMakeCurrent (xdisplay, x11_drawable_get_xid (widget.window), context))
            return false;

        glClear (GL_COLOR_BUFFER_BIT);

        glBegin (GL_TRIANGLES);
            glIndexi (0);
            glColor3f (1.0f, 0.0f, 0.0f);
            glVertex2i (0, 1);
            glIndexi (0);
            glColor3f (0.0f, 1.0f, 0.0f);
            glVertex2i (-1, -1);
            glIndexi (0);
            glColor3f (0.0f, 0.0f, 1.0f);
            glVertex2i (1, -1);
        glEnd ();

        glXSwapBuffers (xdisplay, x11_drawable_get_xid (widget.window));

        return true;
    }
}

void main (string[] args) {
    Gtk.init (ref args);

    var sample = new GLXSample ();
    sample.show_all ();

    Gtk.main ();
}

编译命令：

$ valac --pkg gtk+-2.0 --pkg gdk-x11-2.0 --pkg gl --pkg glx glx-sample.vala

　　从这儿看，基于的是gtk+-2.0，同时需要gl.vapi与glx.vapi，可以到

https://wiki.gnome.org/Projects/Vala/ExternalBindings

下去获取

在ubuntu 18.04编译时，有部分编译错误，修正后的vala代码（编译通过，并不能运行）

using Gtk;
using Gdk;
using GLX;
using GL;

class GLXSample : Gtk.Window {

    private X.Display xdisplay;
    private GLX.Context context;
    private XVisualInfo xvinfo;

    public GLXSample () {
        this.title = "OpenGL with GLX";
        set_reallocate_redraws (true);
        destroy.connect (Gtk.main_quit);

        int[] attrlist = {
            GLX_RGBA,
            GLX_RED_SIZE, 1,
            GLX_GREEN_SIZE, 1,
            GLX_BLUE_SIZE, 1,
            GLX_DOUBLEBUFFER, 0
        };

        this.xdisplay ;//＝ x11_get_default_xdisplay ();
        if (!glXQueryExtension (xdisplay, null, null)) {
            stderr.printf ("OpenGL not supported
");
        }

        this.xvinfo = glXChooseVisual (xdisplay, x11_get_default_screen (), attrlist);
        if (xvinfo == null) {
            stderr.printf ("Error configuring OpenGL
");
        }

        var drawing_area = new DrawingArea ();
        drawing_area.set_size_request (300, 300);
        drawing_area.set_double_buffered (false);

        this.context = glXCreateContext (xdisplay, xvinfo, null, true);

        drawing_area.configure_event.connect (on_configure_event);
        drawing_area.expose_event.connect (on_expose_event);

        add (drawing_area);
    }

    private bool on_configure_event (Widget widget, Gdk.EventConfigure event) {
        if (!glXMakeCurrent (xdisplay, x11_drawable_get_xid (widget.window), context))
            return false;

        glViewport (0, 0, (GLsizei) widget.allocation.width,
                          (GLsizei) widget.allocation.height);

        return true;
    }

    private bool on_expose_event (Widget widget, Gdk.EventExpose event) {
        if (!glXMakeCurrent (xdisplay, x11_drawable_get_xid (widget.window), context))
            return false;

        glClear (GL_COLOR_BUFFER_BIT);

        glBegin (GL_TRIANGLES);
            glIndexi (0);
            glColor3f (1.0f, 0.0f, 0.0f);
            glVertex2i (0, 1);
            glIndexi (0);
            glColor3f (0.0f, 1.0f, 0.0f);
            glVertex2i (-1, -1);
            glIndexi (0);
            glColor3f (0.0f, 0.0f, 1.0f);
            glVertex2i (1, -1);
        glEnd ();

        glXSwapBuffers (xdisplay, x11_drawable_get_xid (widget.window));

        return true;
    }
}

void main (string[] args) {
    Gtk.init (ref args);

    var sample = new GLXSample ();
    sample.show_all ();

    Gtk.main ();
}

针对gtk+-3.0的编译链接命令需要修改为：

$ valac --pkg gtk+-3.0 --pkg gdk-x11-3.0 --pkg gl --pkg glx glx-sample.vala

相应的vala代码为：

using Gtk;
using Gdk.X11;
using Gdk;
using GLX;
using GL;

class GLXSample : Gtk.Window {

    //private X.Display xdisplay;
    private GLX.Context context;
    private XVisualInfo xvinfo;

    public GLXSample () {
        this.title = "OpenGL with GLX";
        set_reallocate_redraws (true);
        destroy.connect (Gtk.main_quit);

        int[] attrlist = {
            GLX_RGBA,
            GLX_RED_SIZE, 1,
            GLX_GREEN_SIZE, 1,
            GLX_BLUE_SIZE, 1,
            GLX_DOUBLEBUFFER, 0
        };

        var drawing_area = new DrawingArea ();
        drawing_area.set_size_request (300, 300);
        drawing_area.set_double_buffered (false);
        drawing_area.show();
        
        var gdk_display = drawing_area.get_display() as Gdk.X11.Display;
        //var xdisplay = gdk_display.get_xdisplay ();
        if (!glXQueryExtension (gdk_display.get_xdisplay (), null, null)) {
            stderr.printf ("OpenGL not supported
");
        }

        var gdk_screen = gdk_display.get_default_screen () as Gdk.X11.Screen;
        this.xvinfo = glXChooseVisual (gdk_display.get_xdisplay (), gdk_screen.get_screen_number(), attrlist);
        if (xvinfo == null) {
            stderr.printf ("Error configuring OpenGL
");
        }

        this.context = glXCreateContext (gdk_display.get_xdisplay (), xvinfo, null, true);

        drawing_area.size_allocate.connect (on_size_allocate_event);
        drawing_area.draw.connect (on_draw_event);

        add (drawing_area);
    }

    private void on_size_allocate_event (Widget widget, Gtk.Allocation allocation) {
        var gdk_window = widget.get_window();
        if (!(gdk_window is Gdk.Window))
            return;
        var gdk_display = widget.get_display() as Gdk.X11.Display;
        //var xdisplay = gdk_display.get_xdisplay ();
        if (!glXMakeCurrent (gdk_display.get_xdisplay (), Gdk.X11Window.get_xid(gdk_window), context))
            return ;//false;

        glViewport (0, 0, (GLsizei) allocation.width,
                          (GLsizei) allocation.height);

        return ;//true;
    }

    private bool on_draw_event (Widget widget, Cairo.Context cr) {
        var gdk_window = widget.get_window() as Gdk.X11.Window;
        if (!(gdk_window is Gdk.Window))
            return false;

        var gdk_display = widget.get_display() as Gdk.X11.Display;
        //var xdisplay = gdk_display.get_xdisplay ();

        if (!glXMakeCurrent (gdk_display.get_xdisplay (), gdk_window.get_xid(), context))
            return false;

        glClear (GL_COLOR_BUFFER_BIT);

        glBegin (GL_TRIANGLES);
            glIndexi (0);
            glColor3f (1.0f, 0.0f, 0.0f);
            glVertex2i (0, 1);
            glIndexi (0);
            glColor3f (0.0f, 1.0f, 0.0f);
            glVertex2i (-1, -1);
            glIndexi (0);
            glColor3f (0.0f, 0.0f, 1.0f);
            glVertex2i (1, -1);
        glEnd ();

        glXSwapBuffers (gdk_display.get_xdisplay (), gdk_window.get_xid());//x11_drawable_get_xid (widget.window));

        return true;
    }
}

void main (string[] args) {
    Gtk.init (ref args);

    var sample = new GLXSample ();
    sample.show_all ();

    Gtk.main ();
}

vala生成的代码中，基于opengl的会自动包含glew.h，狗屎，又不一定要用到，注释掉后的c代码

/* gtk3_glx-sample.c generated by valac 0.40.23, the Vala compiler
 * generated from gtk3_glx-sample.vala, do not modify */



#include <glib.h>
#include <glib-object.h>
#include <gtk/gtk.h>
#include <GL/glx.h>
#include <gdk/gdkx.h>
#include <stdio.h>
#include <gdk/gdk.h>
#include <cairo.h>
//#include <GL/glew.h>
#include <stdlib.h>
#include <string.h>


#define TYPE_GLX_SAMPLE (glx_sample_get_type ())
#define GLX_SAMPLE(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), TYPE_GLX_SAMPLE, GLXSample))
#define GLX_SAMPLE_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), TYPE_GLX_SAMPLE, GLXSampleClass))
#define IS_GLX_SAMPLE(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), TYPE_GLX_SAMPLE))
#define IS_GLX_SAMPLE_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), TYPE_GLX_SAMPLE))
#define GLX_SAMPLE_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), TYPE_GLX_SAMPLE, GLXSampleClass))

typedef struct _GLXSample GLXSample;
typedef struct _GLXSampleClass GLXSampleClass;
typedef struct _GLXSamplePrivate GLXSamplePrivate;
enum  {
    GLX_SAMPLE_0_PROPERTY,
    GLX_SAMPLE_NUM_PROPERTIES
};
static GParamSpec* glx_sample_properties[GLX_SAMPLE_NUM_PROPERTIES];
#define _XFree0(var) ((var == NULL) ? NULL : (var = (XFree (var), NULL)))
#define _g_object_unref0(var) ((var == NULL) ? NULL : (var = (g_object_unref (var), NULL)))

struct _GLXSample {
    GtkWindow parent_instance;
    GLXSamplePrivate * priv;
};

struct _GLXSampleClass {
    GtkWindowClass parent_class;
};

struct _GLXSamplePrivate {
    GLXContext context;
    XVisualInfo* xvinfo;
};


static gpointer glx_sample_parent_class = NULL;

GType glx_sample_get_type (void) G_GNUC_CONST;
#define GLX_SAMPLE_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), TYPE_GLX_SAMPLE, GLXSamplePrivate))
GLXSample* glx_sample_new (void);
GLXSample* glx_sample_construct (GType object_type);
static void _gtk_main_quit_gtk_widget_destroy (GtkWidget* _sender,
                                        gpointer self);
static void glx_sample_on_size_allocate_event (GLXSample* self,
                                        GtkWidget* widget,
                                        GtkAllocation* allocation);
static void _glx_sample_on_size_allocate_event_gtk_widget_size_allocate (GtkWidget* _sender,
                                                                  GtkAllocation* allocation,
                                                                  gpointer self);
static gboolean glx_sample_on_draw_event (GLXSample* self,
                                   GtkWidget* widget,
                                   cairo_t* cr);
static gboolean _glx_sample_on_draw_event_gtk_widget_draw (GtkWidget* _sender,
                                                    cairo_t* cr,
                                                    gpointer self);
static void glx_sample_finalize (GObject * obj);
void _vala_main (gchar** args,
                 int args_length1);


static void
_gtk_main_quit_gtk_widget_destroy (GtkWidget* _sender,
                                   gpointer self)
{
    gtk_main_quit ();
}


static gpointer
_g_object_ref0 (gpointer self)
{
    return self ? g_object_ref (self) : NULL;
}


static void
_glx_sample_on_size_allocate_event_gtk_widget_size_allocate (GtkWidget* _sender,
                                                             GtkAllocation* allocation,
                                                             gpointer self)
{
    glx_sample_on_size_allocate_event ((GLXSample*) self, _sender, allocation);
}


static gboolean
_glx_sample_on_draw_event_gtk_widget_draw (GtkWidget* _sender,
                                           cairo_t* cr,
                                           gpointer self)
{
    gboolean result;
    result = glx_sample_on_draw_event ((GLXSample*) self, _sender, cr);
    return result;
}


GLXSample*
glx_sample_construct (GType object_type)
{
    GLXSample * self = NULL;
    gint* attrlist = NULL;
    gint* _tmp0_;
    gint attrlist_length1;
    gint _attrlist_size_;
    GtkDrawingArea* drawing_area = NULL;
    GtkDrawingArea* _tmp1_;
    GtkDrawingArea* _tmp2_;
    GtkDrawingArea* _tmp3_;
    GtkDrawingArea* _tmp4_;
    GdkX11Display* gdk_display = NULL;
    GtkDrawingArea* _tmp5_;
    GdkDisplay* _tmp6_;
    GdkX11Display* _tmp7_;
    GdkX11Display* _tmp8_;
    Display* _tmp9_;
    GdkX11Screen* gdk_screen = NULL;
    GdkX11Display* _tmp11_;
    GdkScreen* _tmp12_;
    GdkX11Screen* _tmp13_;
    GdkX11Display* _tmp14_;
    Display* _tmp15_;
    GdkX11Screen* _tmp16_;
    gint* _tmp17_;
    gint _tmp17__length1;
    XVisualInfo* _tmp18_;
    XVisualInfo* _tmp19_;
    GdkX11Display* _tmp21_;
    Display* _tmp22_;
    XVisualInfo* _tmp23_;
    GtkDrawingArea* _tmp24_;
    GtkDrawingArea* _tmp25_;
    GtkDrawingArea* _tmp26_;
    self = (GLXSample*) g_object_new (object_type, NULL);
    gtk_window_set_title ((GtkWindow*) self, "OpenGL with GLX");
    gtk_container_set_reallocate_redraws ((GtkContainer*) self, TRUE);
    g_signal_connect ((GtkWidget*) self, "destroy", (GCallback) _gtk_main_quit_gtk_widget_destroy, NULL);
    _tmp0_ = g_new0 (gint, 9);
    _tmp0_[0] = GLX_RGBA;
    _tmp0_[1] = GLX_RED_SIZE;
    _tmp0_[2] = 1;
    _tmp0_[3] = GLX_GREEN_SIZE;
    _tmp0_[4] = 1;
    _tmp0_[5] = GLX_BLUE_SIZE;
    _tmp0_[6] = 1;
    _tmp0_[7] = GLX_DOUBLEBUFFER;
    _tmp0_[8] = 0;
    attrlist = _tmp0_;
    attrlist_length1 = 9;
    _attrlist_size_ = attrlist_length1;
    _tmp1_ = (GtkDrawingArea*) gtk_drawing_area_new ();
    g_object_ref_sink (_tmp1_);
    drawing_area = _tmp1_;
    _tmp2_ = drawing_area;
    gtk_widget_set_size_request ((GtkWidget*) _tmp2_, 300, 300);
    _tmp3_ = drawing_area;
    gtk_widget_set_double_buffered ((GtkWidget*) _tmp3_, FALSE);
    _tmp4_ = drawing_area;
    gtk_widget_show ((GtkWidget*) _tmp4_);
    _tmp5_ = drawing_area;
    _tmp6_ = gtk_widget_get_display ((GtkWidget*) _tmp5_);
    _tmp7_ = _g_object_ref0 (G_TYPE_CHECK_INSTANCE_TYPE (_tmp6_, gdk_x11_display_get_type ()) ? ((GdkX11Display*) _tmp6_) : NULL);
    gdk_display = _tmp7_;
    _tmp8_ = gdk_display;
    _tmp9_ = gdk_x11_display_get_xdisplay (_tmp8_);
    if (!glXQueryExtension (_tmp9_, NULL, NULL)) {
        FILE* _tmp10_;
        _tmp10_ = stderr;
        fprintf (_tmp10_, "OpenGL not supported
");
    }
    _tmp11_ = gdk_display;
    _tmp12_ = gdk_display_get_default_screen ((GdkDisplay*) _tmp11_);
    _tmp13_ = _g_object_ref0 (G_TYPE_CHECK_INSTANCE_TYPE (_tmp12_, gdk_x11_screen_get_type ()) ? ((GdkX11Screen*) _tmp12_) : NULL);
    gdk_screen = _tmp13_;
    _tmp14_ = gdk_display;
    _tmp15_ = gdk_x11_display_get_xdisplay (_tmp14_);
    _tmp16_ = gdk_screen;
    _tmp17_ = attrlist;
    _tmp17__length1 = attrlist_length1;
    _tmp18_ = glXChooseVisual (_tmp15_, gdk_x11_screen_get_screen_number (_tmp16_), _tmp17_);
    _XFree0 (self->priv->xvinfo);
    self->priv->xvinfo = _tmp18_;
    _tmp19_ = self->priv->xvinfo;
    if (_tmp19_ == NULL) {
        FILE* _tmp20_;
        _tmp20_ = stderr;
        fprintf (_tmp20_, "Error configuring OpenGL
");
    }
    _tmp21_ = gdk_display;
    _tmp22_ = gdk_x11_display_get_xdisplay (_tmp21_);
    _tmp23_ = self->priv->xvinfo;
    self->priv->context = glXCreateContext (_tmp22_, _tmp23_, NULL, TRUE);
    _tmp24_ = drawing_area;
    g_signal_connect_object ((GtkWidget*) _tmp24_, "size-allocate", (GCallback) _glx_sample_on_size_allocate_event_gtk_widget_size_allocate, self, 0);
    _tmp25_ = drawing_area;
    g_signal_connect_object ((GtkWidget*) _tmp25_, "draw", (GCallback) _glx_sample_on_draw_event_gtk_widget_draw, self, 0);
    _tmp26_ = drawing_area;
    gtk_container_add ((GtkContainer*) self, (GtkWidget*) _tmp26_);
    _g_object_unref0 (gdk_screen);
    _g_object_unref0 (gdk_display);
    _g_object_unref0 (drawing_area);
    attrlist = (g_free (attrlist), NULL);
    return self;
}


GLXSample*
glx_sample_new (void)
{
    return glx_sample_construct (TYPE_GLX_SAMPLE);
}


static void
glx_sample_on_size_allocate_event (GLXSample* self,
                                   GtkWidget* widget,
                                   GtkAllocation* allocation)
{
    GdkWindow* gdk_window = NULL;
    GdkWindow* _tmp0_;
    GdkWindow* _tmp1_;
    GdkWindow* _tmp2_;
    GdkX11Display* gdk_display = NULL;
    GdkDisplay* _tmp3_;
    GdkX11Display* _tmp4_;
    GdkX11Display* _tmp5_;
    Display* _tmp6_;
    GdkWindow* _tmp7_;
    GLXContext _tmp8_;
    GtkAllocation _tmp9_;
    gint _tmp10_;
    GtkAllocation _tmp11_;
    gint _tmp12_;
    g_return_if_fail (self != NULL);
    g_return_if_fail (widget != NULL);
    g_return_if_fail (allocation != NULL);
    _tmp0_ = gtk_widget_get_window (widget);
    _tmp1_ = _g_object_ref0 (_tmp0_);
    gdk_window = _tmp1_;
    _tmp2_ = gdk_window;
    if (!G_TYPE_CHECK_INSTANCE_TYPE (_tmp2_, gdk_window_get_type ())) {
        _g_object_unref0 (gdk_window);
        return;
    }
    _tmp3_ = gtk_widget_get_display (widget);
    _tmp4_ = _g_object_ref0 (G_TYPE_CHECK_INSTANCE_TYPE (_tmp3_, gdk_x11_display_get_type ()) ? ((GdkX11Display*) _tmp3_) : NULL);
    gdk_display = _tmp4_;
    _tmp5_ = gdk_display;
    _tmp6_ = gdk_x11_display_get_xdisplay (_tmp5_);
    _tmp7_ = gdk_window;
    _tmp8_ = self->priv->context;
    if (!glXMakeCurrent (_tmp6_, (GLXDrawable) gdk_x11_window_get_xid (_tmp7_), _tmp8_)) {
        _g_object_unref0 (gdk_display);
        _g_object_unref0 (gdk_window);
        return;
    }
    _tmp9_ = *allocation;
    _tmp10_ = _tmp9_.width;
    _tmp11_ = *allocation;
    _tmp12_ = _tmp11_.height;
    glViewport ((GLint) 0, (GLint) 0, (GLsizei) _tmp10_, (GLsizei) _tmp12_);
    _g_object_unref0 (gdk_display);
    _g_object_unref0 (gdk_window);
    return;
}


static gboolean
glx_sample_on_draw_event (GLXSample* self,
                          GtkWidget* widget,
                          cairo_t* cr)
{
    gboolean result = FALSE;
    GdkX11Window* gdk_window = NULL;
    GdkWindow* _tmp0_;
    GdkX11Window* _tmp1_;
    GdkX11Window* _tmp2_;
    GdkX11Display* gdk_display = NULL;
    GdkDisplay* _tmp3_;
    GdkX11Display* _tmp4_;
    GdkX11Display* _tmp5_;
    Display* _tmp6_;
    GdkX11Window* _tmp7_;
    GLXContext _tmp8_;
    GdkX11Display* _tmp9_;
    Display* _tmp10_;
    GdkX11Window* _tmp11_;
    g_return_val_if_fail (self != NULL, FALSE);
    g_return_val_if_fail (widget != NULL, FALSE);
    g_return_val_if_fail (cr != NULL, FALSE);
    _tmp0_ = gtk_widget_get_window (widget);
    _tmp1_ = _g_object_ref0 (G_TYPE_CHECK_INSTANCE_TYPE (_tmp0_, gdk_x11_window_get_type ()) ? ((GdkX11Window*) _tmp0_) : NULL);
    gdk_window = _tmp1_;
    _tmp2_ = gdk_window;
    if (!G_TYPE_CHECK_INSTANCE_TYPE (_tmp2_, gdk_window_get_type ())) {
        result = FALSE;
        _g_object_unref0 (gdk_window);
        return result;
    }
    _tmp3_ = gtk_widget_get_display (widget);
    _tmp4_ = _g_object_ref0 (G_TYPE_CHECK_INSTANCE_TYPE (_tmp3_, gdk_x11_display_get_type ()) ? ((GdkX11Display*) _tmp3_) : NULL);
    gdk_display = _tmp4_;
    _tmp5_ = gdk_display;
    _tmp6_ = gdk_x11_display_get_xdisplay (_tmp5_);
    _tmp7_ = gdk_window;
    _tmp8_ = self->priv->context;
    if (!glXMakeCurrent (_tmp6_, (GLXDrawable) gdk_x11_window_get_xid (_tmp7_), _tmp8_)) {
        result = FALSE;
        _g_object_unref0 (gdk_display);
        _g_object_unref0 (gdk_window);
        return result;
    }
    glClear ((GLbitfield) GL_COLOR_BUFFER_BIT);
    glBegin ((GLenum) GL_TRIANGLES);
    glIndexi ((GLint) 0);
    glColor3f ((GLfloat) 1.0f, (GLfloat) 0.0f, (GLfloat) 0.0f);
    glVertex2i ((GLint) 0, (GLint) 1);
    glIndexi ((GLint) 0);
    glColor3f ((GLfloat) 0.0f, (GLfloat) 1.0f, (GLfloat) 0.0f);
    glVertex2i ((GLint) -1, (GLint) -1);
    glIndexi ((GLint) 0);
    glColor3f ((GLfloat) 0.0f, (GLfloat) 0.0f, (GLfloat) 1.0f);
    glVertex2i ((GLint) 1, (GLint) -1);
    glEnd ();
    _tmp9_ = gdk_display;
    _tmp10_ = gdk_x11_display_get_xdisplay (_tmp9_);
    _tmp11_ = gdk_window;
    glXSwapBuffers (_tmp10_, (GLXDrawable) gdk_x11_window_get_xid (_tmp11_));
    result = TRUE;
    _g_object_unref0 (gdk_display);
    _g_object_unref0 (gdk_window);
    return result;
}


static void
glx_sample_class_init (GLXSampleClass * klass)
{
    glx_sample_parent_class = g_type_class_peek_parent (klass);
    g_type_class_add_private (klass, sizeof (GLXSamplePrivate));
    G_OBJECT_CLASS (klass)->finalize = glx_sample_finalize;
}


static void
glx_sample_instance_init (GLXSample * self)
{
    self->priv = GLX_SAMPLE_GET_PRIVATE (self);
}


static void
glx_sample_finalize (GObject * obj)
{
    GLXSample * self;
    self = G_TYPE_CHECK_INSTANCE_CAST (obj, TYPE_GLX_SAMPLE, GLXSample);
    _XFree0 (self->priv->xvinfo);
    G_OBJECT_CLASS (glx_sample_parent_class)->finalize (obj);
}


GType
glx_sample_get_type (void)
{
    static volatile gsize glx_sample_type_id__volatile = 0;
    if (g_once_init_enter (&glx_sample_type_id__volatile)) {
        static const GTypeInfo g_define_type_info = { sizeof (GLXSampleClass), (GBaseInitFunc) NULL, (GBaseFinalizeFunc) NULL, (GClassInitFunc) glx_sample_class_init, (GClassFinalizeFunc) NULL, NULL, sizeof (GLXSample), 0, (GInstanceInitFunc) glx_sample_instance_init, NULL };
        GType glx_sample_type_id;
        glx_sample_type_id = g_type_register_static (gtk_window_get_type (), "GLXSample", &g_define_type_info, 0);
        g_once_init_leave (&glx_sample_type_id__volatile, glx_sample_type_id);
    }
    return glx_sample_type_id__volatile;
}


void
_vala_main (gchar** args,
            int args_length1)
{
    GLXSample* sample = NULL;
    GLXSample* _tmp0_;
    gtk_init (&args_length1, &args);
    _tmp0_ = glx_sample_new ();
    g_object_ref_sink (_tmp0_);
    sample = _tmp0_;
    gtk_widget_show_all ((GtkWidget*) sample);
    gtk_main ();
    _g_object_unref0 (sample);
}


int
main (int argc,
      char ** argv)
{
    _vala_main (argv, argc);
    return 0;
}