Location - Location - Location

The prepositions an, auf, hinter, in, neben, über, unter, vor, zwischen are all about location in relation to an object (two or more objects for zwischen). I hadn't thought about them for years in terms of being a group of words about location because I'd learnt them as a list of prepositions that can govern either the dative or accusative in the substantives that follow. I find it very useful to go back to the basics of grammar from time to time and work through exercises to check out my competence with things I've often taken for granted.

So what determines whether the substantive ends up in the dative or the accusative? Let's take a look at some sentences about birds and windows.

1. Die Vögel warten im Winter vor dem Fenster.
2. Ein Vogel war vor das Fenster geklatscht.
3. Ich habe vor dem Fenster ein Futterplatz für die Vögel eingerichtet.
4. Das Tarnnetz wird vor das Fenster gespannen und sorgt dafür, dass Bewegungen im inneren des Autos für die Vögel  weniger sichtbar sind.

Number 1 is obviously dative because what is happening has no movement, it's about being in a place in relation to an object. Typical verbs for these nicht-zielgerichtete Geschehen are warten, sitzen, stehen, wohnen.

Number 2 is accusative because there is movement in relation to the object. Grammar books say things like: Akkusativ erscheint bei zielgerichtetem Geschehen, das richtungsbetont ist (setzen, stellen, kommen).

Number 3 is not quite so obvious at first because putting something up seems to imply movement. However, the movement is not related to the window. The sentence only says the action happened somewhere in front of the window, there is no movement in any direction in relation to the window. So this time it's dative.

So how does number 4 differ? I struggled with the reasoning and ended up thinking in English. What is happening is something is being stretched over the window rather than something being stretched between two points that happen to be somewhere in front of the window. The action directly involves the window, it's not an action at a point some distance in front of the window. I've never come across an example that has puzzled me as much as this and my reasoning may be false. I would welcome a clearer explanation for this one.