required parameter op missing<br /><pre>
Usage: <b>/lib/img/tiling.php</b>?op=<i>n</i>[&amp;<i>option</i> ...]
Options:
    f<i>n</i>=foo   file parameters
    op=<i>n</i>     option
	h=<i>n</i>      output height
    p<i>n</i>=foo   op-specific parameters
	w=<i>n</i>      output width
Op-specific parameters:
    op=1      vertical strip collage      [requires: f1 f2]
        p1=<i>n</i>  strip width in px           [default: 1]
    op=2      horizontal strip collage    [requires: f1 f2]
        p1=<i>n</i>  strip height in px          [default: 1]
    op=3      checkerboard collage        [requires: f1 f2]
        p1=<i>n</i>  strip width in px           [default: 100]
        p2=<i>n</i>  strip height in px          [default: 100]
    op=4      tile                        [requires: f1]
        p1=<i>n</i>  horizontal repetition count [default: 2]
        p2=<i>n</i>  vertical repetition count   [default: 2]
    op=5      generate hex tile           [requires: f1]
        p1=<i>n</i>  base as fraction of width   [default: .5]
    op=6      tile hex tile               [requires: f1, w]
        p1=<i>n</i>  base as fraction of width   [default: .5]
        p2=<i>n</i>  horizontal repetition count [default: 2]
        p3=<i>n</i>  vertical repetition count   [default: 2]
</pre>