GDK 3 Reference Manual: GdkGLContext

## GdkGLContext GdkGLContext — OpenGL context |

## Functions

GdkWindow * | gdk_gl_context_get_window ()
void | gdk_gl_context_make_current ()
void | gdk_gl_context_clear_current ()
GdkGLContext * | gdk_gl_context_get_current ()
#define | GDK_GL_ERROR
#define | GDK_TYPE_GL_ERROR
#define | GDK_TYPE_GL_PROFILE

## Properties

GdkDisplay * | display | Read / Write / Construct Only
GdkGLProfile | profile | Read / Write / Construct Only
GdkGLContext * | shared-context | Read / Write / Construct Only
GdkWindow * | window | Read / Write / Construct Only

## Types and Values

| GdkGLContext
enum | GdkGLProfile
enum | GdkGLError

## Object Hierarchy

        GObject
        ╰── GdkGLContext

## Includes

    #include <gdk/gdk.h>

## Description

GdkGLContext is an object representing the platform-specific OpenGL drawing context.

GdkGLContexts are created for a GdkWindow using `gdk_window_create_gl_context()`, and the context will match the GdkVisual of the window.

A GdkGLContext is not tied to any particular normal framebuffer. For instance, it cannot draw to the GdkWindow back buffer. The GDK repaint system is in full control of the painting to that. Instead, you can create render buffers or textures and use `gdk_cairo_draw_from_gl()` in the draw function of your widget to draw them. Then GDK will handle the integration of your rendering with that of other widgets.

Support for GdkGLContext is platform-specific, context creation can fail, returning `NULL` context.

A GdkGLContext has to be made "current" in order to start using it, otherwise any OpenGL call will be ignored.

#### Creating a new OpenGL context

In order to create a new GdkGLContext instance you need a GdkWindow, which you typically get during the realize call of a widget.

#### Using a GdkGLContext

You will need to make the GdkGLContext the current context before issuing OpenGL calls; the system sends OpenGL commands to whichever context is current. It is possible to have multiple contexts, so you always need to ensure that the one which you want to draw with is the current one before issuing commands:

    1
    gdk_gl_context_make_current (context);

You can now perform your drawing using OpenGL commands.

You can check which GdkGLContext is the current one by using `gdk_gl_context_get_current()`; you can also unset any GdkGLContext that is currently set by calling `gdk_gl_context_clear_current()`.

## Functions

### gdk_gl_context_get_window ()

    GdkWindow *
    gdk_gl_context_get_window (GdkGLContext *context);

Retrieves the GdkWindow used by the `context` .

#### Parameters

context | a GdkGLContext |

#### Returns

a GdkWindow or `NULL`.

[transfer none]

Since 3.16

### gdk_gl_context_make_current ()

    void
    gdk_gl_context_make_current (GdkGLContext *context);

Makes the `context` the current one.

#### Parameters

context | a GdkGLContext |

Since 3.16

### gdk_gl_context_clear_current ()

    void
    gdk_gl_context_clear_current (void);

Clears the current GdkGLContext.

Any OpenGL call after this function returns will be ignored until `gdk_gl_context_make_current()` is called.

Since 3.16

### gdk_gl_context_get_current ()

    GdkGLContext *
    gdk_gl_context_get_current (void);

Retrieves the current GdkGLContext.

#### Returns

the current GdkGLContext, or `NULL`.

[transfer none]

Since 3.16

### GDK_GL_ERROR

    #define GDK_GL_ERROR       (gdk_gl_error_quark ())

### GDK_TYPE_GL_ERROR

    #define GDK_TYPE_GL_ERROR (gdk_gl_error_get_type ())

### GDK_TYPE_GL_PROFILE

    #define GDK_TYPE_GL_PROFILE (gdk_gl_profile_get_type ())

## Types and Values

### GdkGLContext

    typedef struct _GdkGLContext GdkGLContext;

### enum GdkGLProfile

...

#### Members

GDK_GL_PROFILE_DEFAULT | ... |
GDK_GL_PROFILE_LEGACY | ... |
GDK_GL_PROFILE_3_2_CORE | ... |

### enum GdkGLError

#### Members

GDK_GL_ERROR_NOT_AVAILABLE |  |
GDK_GL_ERROR_UNSUPPORTED_FORMAT |  |
GDK_GL_ERROR_UNSUPPORTED_PROFILE |  |

## Property Details

### The `“display”` property

      “display”                  GdkDisplay *

The GdkWindow the gl context is bound to.

Flags: Read / Write / Construct Only

Since 3.16

### The `“profile”` property

      “profile”                  GdkGLProfile

The GdkGLProfile of the context

Flags: Read / Write / Construct Only

Default value: GDK_GL_PROFILE_DEFAULT

Since 3.16

### The `“shared-context”` property

      “shared-context”           GdkGLContext *

The GdkGLContext that this context is sharing data with, or NULL

Flags: Read / Write / Construct Only

Since 3.16

### The `“window”` property

      “window”                   GdkWindow *

The GdkWindow the gl context is bound to.

Flags: Read / Write / Construct Only

Since 3.16