---
name: "request_scroll"
section: "3alleg"
platform: "linux"
package: "liballegro-doc"
version: "2:4.2.2-2.2"
release: "Debian 6.0 (Squeeze)"
platforms: ["linux"]
url: "https://new.carta.tech/request_scroll"
---

# request\_scroll(3alleg)

Queues a hardware scroll request with triple buffering. Allegro game programming library.

## NAME

request\_scroll - Queues a hardware scroll request with triple buffering. Allegro game programming library.

## SYNOPSIS

**#include \<allegro.h\>**

**int request\_scroll(int x, int y);**

## DESCRIPTION

This function is used for triple buffering. It requests a hardware scroll  to the specified position, but returns immediately rather than waiting  for a retrace. The scroll will then take place during the next vertical  retrace, but you can carry on running other code in the meantime and use  the poll\_scroll() routine to detect when the flip has actually taken  place.

Triple buffering is only possible with certain drivers: you can look at the  GFX\_CAN\_TRIPLE\_BUFFER bit in the gfx\_capabilities flag to see if it will  work with the current driver.

## RETURN VALUE

This function returns zero on success, non-zero otherwise.

## SEE ALSO

[**poll\_scroll**(3alleg)](/poll_scroll/3alleg.md), [**request\_video\_bitmap**(3alleg)](/request_video_bitmap/3alleg.md), [**gfx\_capabilities**(3alleg)](/gfx_capabilities/3alleg.md), [**scroll\_screen**(3alleg)](/scroll_screen/3alleg.md)