OpenGL-Capable Widget

OpenGL-Capable Widget — OpenGL extension to GtkWidget API

Functions

Includes

#include <gtk/gtkgl.h>

Description

GtkGLExt is an extension to GTK which adds OpenGL capabilities to GtkWidget. Its use is quite simple: use gtk_widget_set_gl_capability to add OpenGL support to a widget, it will create a OpenGL drawable (GdkGLDrawable) for the widget, which can be obtained via gtk_widget_get_gl_drawable. OpenGL rendering context (GdkGLContext) can also be obtained via gtk_widget_get_gl_context. With GdkGLDrawable and GdkGLContext, gdk_gl_drawable_gl_begin and gdk_gl_drawable_gl_end can be called, and OpenGL function calls can be made between those two functions.

Functions

gtk_widget_set_gl_capability ()

gboolean
gtk_widget_set_gl_capability (GtkWidget *widget,
                              GdkGLConfig *glconfig,
                              GdkGLContext *share_list,
                              gboolean direct,
                              int render_type);

Set the OpenGL-capability to the widget . This function prepares the widget for its use with OpenGL.

Parameters

widget

the GtkWidget to be used as the rendering area.

 

glconfig

a GdkGLConfig.

 

share_list

the GdkGLContext with which to share display lists and texture objects. NULL indicates that no sharing is to take place.

 

direct

whether rendering is to be done with a direct connection to the graphics system.

 

render_type

GDK_GL_RGBA_TYPE or GDK_GL_COLOR_INDEX_TYPE (currently not used).

 

Returns

TRUE if it is successful, FALSE otherwise.


gtk_widget_is_gl_capable ()

gboolean
gtk_widget_is_gl_capable (GtkWidget *widget);

Returns whether the widget is OpenGL-capable.

Parameters

widget

a GtkWidget.

 

Returns

TRUE if the widget is OpenGL-capable, FALSE otherwise.


gtk_widget_get_gl_config ()

GdkGLConfig *
gtk_widget_get_gl_config (GtkWidget *widget);

Returns the GdkGLConfig referred by the widget .

Parameters

widget

a GtkWidget.

 

Returns

the GdkGLConfig.


gtk_widget_create_gl_context ()

GdkGLContext *
gtk_widget_create_gl_context (GtkWidget *widget,
                              GdkGLContext *share_list,
                              gboolean direct,
                              int render_type);

Creates a new GdkGLContext with the appropriate GdkGLDrawable for this widget. The GL context must be freed when you're finished with it. See also gtk_widget_get_gl_context().

Parameters

widget

a GtkWidget.

 

share_list

the GdkGLContext with which to share display lists and texture objects. NULL indicates that no sharing is to take place.

 

direct

whether rendering is to be done with a direct connection to the graphics system.

 

render_type

GDK_GL_RGBA_TYPE or GDK_GL_COLOR_INDEX_TYPE (currently not used).

 

Returns

the new GdkGLContext.


gtk_widget_get_gl_context ()

GdkGLContext *
gtk_widget_get_gl_context (GtkWidget *widget);

Returns the GdkGLContext with the appropriate GdkGLDrawable for this widget. Unlike the GL context returned by gtk_widget_create_gl_context(), this context is owned by the widget.

GdkGLContext is needed for the function gdk_gl_drawable_begin, or for sharing display lists (see gtk_widget_set_gl_capability()).

Parameters

widget

a GtkWidget.

 

Returns

the GdkGLContext.


gtk_widget_get_gl_window ()

GdkGLWindow *
gtk_widget_get_gl_window (GtkWidget *widget);

Returns the GdkGLWindow owned by the widget .

Parameters

widget

a GtkWidget.

 

Returns

the GdkGLWindow.


gtk_widget_get_gl_drawable()

#define             gtk_widget_get_gl_drawable(widget)

Returns the GdkGLDrawable owned by the widget. In fact, this is macro that casts the result of gtk_widget_get_gl_window to GdkGLDrawable.

Parameters

widget

a GtkWidget.

 

Returns

the GdkGLDrawable.

Types and Values