---
name: "al_create_sub_bitmap"
section: "3alleg5"
platform: "linux"
package: "allegro5-doc"
version: "2:5.2.10.1+dfsg-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/al_create_sub_bitmap/3alleg5"
---

# al\_create\_sub\_bitmap(3alleg5)

Allegro 5 API

## NAME

al\_create\_sub\_bitmap - Allegro 5 API

## SYNOPSIS

-

  ```
  #include <allegro5/allegro.h>
  ALLEGRO_BITMAP *al_create_sub_bitmap(ALLEGRO_BITMAP *parent,
     int x, int y, int w, int h)
  ```

## DESCRIPTION

Creates a sub-bitmap of the parent, at the specified coordinates and of the specified size. A sub-bitmap is a bitmap that shares drawing memory with a pre-existing (parent) bitmap, but possibly with a different size and clipping settings.

The sub-bitmap may originate off or extend past the parent bitmap.

See the discussion in al\_get\_backbuffer(3alleg5) about using sub-bitmaps of the backbuffer.

The parent bitmap’s clipping rectangles are ignored.

If a sub-bitmap was not or cannot be created then NULL is returned.

When you are done with using the sub-bitmap you must call al\_destroy\_bitmap(3alleg5) on it to free any resources allocated for it.

Note that destroying parents of sub-bitmaps will not destroy the sub-bitmaps; instead the sub-bitmaps become invalid and should no longer be used for drawing - they still must be destroyed with al\_destroy\_bitmap(3alleg5) however. It does not matter whether you destroy a sub-bitmap before or after its parent otherwise.

## SEE ALSO

al\_create\_bitmap(3alleg5)