zoomrectangle switches to full extent sometimes

[silke.reimer@…]

Hallo!

Today I analysed a bug with zoomrectangle: I have a map and I zoom in with a
box. When the x-range of the imgbox exceeds a certain limit, the map is
automatically zooming to full extent of the map. When I passed the same
parameters to the cgi binary everything worked as I expected so this must be a
bug in PHP mapscript.

When I increased the map's maxscale the behaviour vanished but nevertheless I
think that zoomrectangle should be fixed. I don't have time in the moment to dig
deeper into the problem. As far as I found out, it has something to do with the
relation between maxscale, extent and imgbox.

Above you find some values which help perhaps to verify this bug. It would be
nice if someone could confirm the bug.

Many thanks,

       Silke

My mapfile values:  

EXTENT 3052504  5250000 4148254 6099309
MAXSCALE 1.5e+06 # the buggy one
MAXSCALE 1.5e+07 # the one which worked
SIZE 660 500

The behaviour could be seen, when I zoomed in from full extent of the map and
the range between xmin and xmax exceeded 160 px.

PHP-Script to draw image. Please read comments.
<?php

// I tested with mapserver 4.6.0, 4.6.1 and nightly build
dl("php_mapscript.so");

function drawimage($imgbox) {
        $map = ms_newMapObj("mymapfile.map");

        $rect = ms_newrectObj();
        $rect->setextent(3039835.06,5250000,4160922.94,6099309);

        $map->zoomrectangle($imgbox, 660, 500, $rect);
        $image = $map->draw();
        $imageurl = $image->saveWebImage();
        echo($imageurl);
}

$pixext = ms_newrectObj();

// showing the bug
$pixext->setextent(210,190,383,290);
drawimage($pixext);

// zooming to correct extent
$pixext->setextent(238,155,333,261);
drawimage($pixext);

?>