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[edit] Changing Window Frames

Blender uses a novel screen-splitting approach to arranging window frames. Your application window is always a rectangle on your desktop. Blender takes that big frame and divides it up into a number of re-sizable window frames. A window frame contains the workspace for a particular type of window, like a 3D View window, or an Outliner. The idea is that you split up that big application window into any number of smaller (but still rectangular) non-overlapping window frames. That way, each window is always fully visible, and it is very easy to work in one window and hop over to work in another.

[edit] Maximizing a window

You can maximize a window frame to fill the whole application window with the View → Toggle Full Screen menu entry. To return to normal size, use again View → Toggle Full Screen. A quicker way to achieve this is to use ⇧ ShiftSpace, Ctrl↓ or Ctrl↑ to toggle between maximized and framed windows.

[edit] Splitting a window

In the upper right hand corner of a window is the window splitter widget, and it looks like a little ridged thumb grip. It both splits and combines window panes. When you hover over it, your cursor will change to a cross. Left-click and drag it to the left to split the pane vertically, or downward to split it horizontally.

[edit] Joining two windows

In order to merge two windows, they must be the same dimension in the direction you wish to merge. For example, if you want to combine two windows that are side-by-side, they must be the same height. If the one on the left is not the same as the one on the right, you will not be able to combine them horizontally. This is so that the combined window space results in a rectangle. The same rule holds for joining two windows that are stacked on top of one another; they must both have the same width. If the one above is split vertically, you must first merge those two, and then join the bottom one up to the upper one.

To merge the current window with the one to the right, hover your mouse cursor over the window splitter (that little thumb grip in the upper right-hand corner of the window pane). When your cursor changes to the cross, LMB click and drag to the right to begin the process of combining the window with the one to the right. The window to the right will get a little darker, overlaid with an arrow pointing to the right. This indicates that the left (current) window type will "take over" that darkened window pane space. Click to make it happen. If you want the reverse to occur, move your mouse cursor back into the original (left) window, and the original window will instead get the arrow overlay; click and then the right window will take over the original window.

Similarly for combining with the window above; click the thumb grip and move your mouse straight up into the window above, and click to activate. If you press Esc or RMB before clicking on one of the windows, the operation will be aborted.

[edit] Changing window size

You can resize windows by dragging their borders with LMB . Simply move your mouse cursor until it changes to a double-headed arrow, and then click and drag.