---
name: "glXMakeCurrent"
section: "3x"
platform: "linux"
package: "xlibmesa-gl-dev"
version: "4.3.0.dfsg.1-14sarge7"
release: "Debian 3.1 (Sarge)"
platforms: ["linux"]
url: "https://new.carta.tech/glXMakeCurrent"
---

# glXMakeCurrent(3x)

attach a GLX context to a window or a GLX pixmap

## NAME

glXMakeCurrent - attach a GLX context to a window or a GLX pixmap

## C SPECIFICATION

Bool **glXMakeCurrent**( Display *\*dpy*,

```
	GLXDrawable drawable,
	GLXContext ctx )
```

delim $$

## PARAMETERS

- *dpy*

  Specifies the connection to the X server.

- *drawable*

  Specifies a GLX drawable. Must be either an X window ID or a GLX pixmap ID.

- *ctx*

  Specifies a GLX rendering context that is to be attached to *drawable*.

## DESCRIPTION

**glXMakeCurrent** does two things: It makes *ctx* the current GLX rendering context of the calling thread, replacing the previously current context if there was one, and it attaches *ctx* to a GLX drawable, either a window or a GLX pixmap. As a result of these two actions, subsequent GL rendering calls use rendering context *ctx* to modify GLX drawable *drawable*. Because **glXMakeCurrent** always replaces the current rendering context with *ctx*, there can be only one current context per thread.

Pending commands to the previous context, if any, are flushed before it is released.

The first time *ctx* is made current to any thread, its viewport is set to the full size of *drawable*. Subsequent calls by any thread to **glXMakeCurrent** with *ctx* have no effect on its viewport.

To release the current context without assigning a new one, call **glXMakeCurrent** with *drawable* set **None** and *ctx* set to **NULL**

**glXMakeCurrent** returns **True** if it is successful, **False** otherwise. If **False** is returned, the previously current rendering context and drawable (if any) remain unchanged.

## NOTES

A *process* is a single-execution environment, implemented in a single address space, consisting of one or more threads.

A *thread* is one of a set of subprocesses that share a single address space, but maintain separate program counters, stack spaces, and other related global data. A *thread* that is the only member of its subprocess group is equivalent to a *process*.

## ERRORS

**BadMatch** is generated if *drawable* was not created with the same X screen and visual as *ctx*. It is also generated if *drawable* is **None** and *ctx* is not **NULL**.

**BadAccess** is generated if *ctx* was current to another thread at the time **glXMakeCurrent** was called.

**GLXBadDrawable** is generated if *drawable* is not a valid GLX drawable.

**GLXBadContext** is generated if *ctx* is not a valid GLX context.

**GLXBadContextState** is generated if **glXMakeCurrent** is executed between the execution of **glBegin** and the corresponding execution of **glEnd**.

**GLXBadContextState** is also generated if the rendering context current to the calling thread has GL renderer state **GL\_FEEDBACK** or **GL\_SELECT**.

**GLXBadCurrentWindow** is generated if there are pending GL commands for the previous context and the current drawable is a window that is no longer valid.

**BadAlloc** may be generated if the server has delayed allocation of ancillary buffers until **glXMakeCurrent** is called, only to find that it has insufficient resources to complete the allocation.

## SEE ALSO

**glXCreateContext**, **glXCreateGLXPixmap**