.\" Generated by the Allegro makedoc utility
.TH getpixel 3alleg4 "version 4.4.3" "Allegro" "Allegro manual"
.SH NAME
getpixel \- Reads a pixel from a bitmap. Allegro game programming library.\&
.SH SYNOPSIS
.B #include <allegro.h>

.sp
.B int getpixel(BITMAP *bmp, int x, int y);
.SH DESCRIPTION
Reads a pixel from point (x, y) in the bitmap.
.SH "RETURN VALUE"
Returns -1 if the point lies outside the bitmap (ignoring the clipping
rectangle), otherwise the value of the pixel in the color format of the
bitmap.

Warning: -1 is also a valid value for pixels contained in 32-bit bitmaps
with alpha channel (when R,G,B,A are all equal to 255) so you can't use
the test against -1 as a predicate for such bitmaps. In this cases, the
only reliable predicate is is_inside_bitmap().

To extract the individual color components, use the getr() / getg() /
getb() / geta() family of functions.

.SH SEE ALSO
.BR putpixel (3alleg4),
.BR _getpixel (3alleg4),
.BR is_inside_bitmap (3alleg4),
.BR getr (3alleg4),
.BR getg (3alleg4),
.BR getb (3alleg4),
.BR geta (3alleg4),
.BR ex12bit (3alleg4),
.BR exalpha (3alleg4),
.BR exflame (3alleg4),
.BR exlights (3alleg4)