[cairo] Direct manipulation and write to PNG

Carlos López González genetita at gmail.com
Mon Jul 9 13:13:05 PDT 2012

Ok, thank you very much for the quick and helpful response.
After modify the code for little endian system it works great!
> The ARGB32 format docs say:
>  * @CAIRO_FORMAT_ARGB32: each pixel is a 32-bit quantity, with
>  *   alpha in the upper 8 bits, then red, then green, then blue.
>  *   The 32-bit quantities are stored native-endian. Pre-multiplied
>  *   alpha is used. (That is, 50% transparent red is 0x80800000,
>  *   not 0x80ff0000.) (Since 1.0)
> Which means, on a little-endian system, the in-memory layout is BGRA.  But you
> are assuming that it is ARGB in memory.
> behdad


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