For some reason my loop cut and slide doesn’t work the way I want it to. As shown in this picture I want it to go all the way around but for some reason it’s adding in lines. There is no reason why it can’t. I could manually pull out all the polygons subdivide them and add it in. I had the SAME PROBLEM with above the door in this picture where it is white but I I took out the square polygon there, add edges and subdivided them and added the faces in etc to get what the loop cut and slide should have been able to do!
Is there anyway to change the behavior of loop cut and slide or something rather than going and manually doing it myself like this?
Select all (w) remove doubles just to make sure there isn’t any duplicate vertex action going on and things are connected.
Go into wireframe mode and check and make sure there is no accidental interior faces. If there are, Face Select mode and delete them.
If you’re using 2.63+ make sure those are actually quads and not ngons (vertexes can sometimes sneak in there). Loop cut can’t cut through ngons basically. (though it probably wouldn’t triangulate it like in your image)
If it still doesn’t work you can maybe get away with the ol’ fashion select edges subdivide trick:
Its doing that because the face loop is not going all the way around for some reason; the most common reason for this is, as XRG notes, some sort of interior faces or doubled vertix issue. In short, the loop sees that face as the end of the loop so it makes the face next to it into triangles so that the vertixi are connected to the rest of the face
