Template for the node.

I encountered a strange problem, could you please help a newbie?

For theming a specific node, I created a template. I noticed an interesting feature: the function path_to_theme() called in this template returns modules/node... instead of the path to the theme sites/all/themes/....

If I call this function in the body field with the PHP filter enabled, it works fine. However, when called in a separate template for the node, it returns modules/node. ((((((

Why do I need this?)

1 I'm just curious why this happens.

2 How can I avoid having to manually specify the correct path to anything? For me, these are images in the node animated by jQuery scripts. Manually specifying anything is not very interesting.