svg out of screen, is rendered?

Question

Scenario: I have SVG image that I can zoom-in and zoom-out. Depending on the zoom, I will display more/less details on the visible part.

The question is: should I take care of not displaying details on the parts that are not currently visible (out of the screen), or the rendering engine is smart enough to skip (clip) those parts before they are rendered?

Answer 1

Yes, browsers are usually clever enough to not render things outside the viewport area.

Note however that the browser still needs to traverse the entire document tree, so even things outside the viewport area can have an impact. It's usually enough to mark the non-interesting subtrees with display="none" to let the browser skip over them when traversing. On small documents that's usually not something that you need to worry about.