Hello,

as your example code did not really work I created a simple reproduce code here: http://valokuva.org/~mikko/bug19984/

This tests translate and setStrokeOpacity and they seem to be working fine.

You're right. The problem was the ORDER I was doing things. Perhaps this should be better documented since it could definitely be confusing for those not overly familiar with Imagick/ImageMagick.

For example, setStrokeOpacity() does nothing here:

$im = new Imagick();
$im->newImage(200, 200, "gray", "png" );

$draw = new ImagickDraw();
$draw->line(10, 10, 50, 50);
$im->drawImage($draw);

$draw->translate(80, 30);
$draw->setStrokeWidth(10);
$draw->setStrokeColor('black');
$draw->line(10, 10, 50, 50);
$draw->setStrokeOpacity(0.5);
$im->drawImage($draw);

header("Content-Type: image/png");
echo $im;

All I did was switch the order of the setStrokeOpacity() to be after the line()

Sure, that is the behavior. Without this behavior it wouldn't be possible to draw things with different settings within the same object. 

The documentation really needs a large overhaul but there are only so many hours in a day.