[NTG-context] layer placement question

[Henning Hraban Ramm]

Another question, regarding layer placement:

\def\bleed{3mm}
\setvalue{LogoHeight}{20mm}
\setvalue{LogoWidth}{60mm}
\setvalue{LogoHOffset}{130mm}

\definelayer[logolayer]
	[x=-\bleed, y=-\bleed,
	width=\paperwidth, height=\paperheight]

\setlayerframed[logolayer]
	[y=-\bleed, x=\dimexpr(\getvalue{LogoHOffset}+\bleed)]
	[height=\dimexpr(\getvalue{LogoHeight}+\bleed),
	width=\getvalue{LogoWidth},
	frame=off, offset=0mm, align=low,
	background=color, backgroundcolor=red]{my logo}

I would expect that the x/y coordinates in \setlayer(framed) relate  
to the layer's origin (-3, -3) and thus my logo gets placed at (130,  
-3).
But in fact it's placed at (133, -3), i.e. x starts at 0 instead of  
-3. Why?

Grüßlis vom Hraban!
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