View Menu features - explanation needed

[ozaz]

I'm trying to understand the features available in the View menu (of the window that the guest OS runs in). I've been unable to locate a section in the manual which focusses specifically on the View menu, and haven't found thorough explanations for all the features.

Perhaps they're considered intuitive and not in need of full documentation, but they're not all intuitive to me and I'd be grateful if someone could help me understand...

Scaled mode vs auto-resize guest display
I don't entirely understand what the difference between these two are. Also, it seems possible to have both of these enabled at the same time (both having the downward pointing icon over their menu entry). When this happens, is one taking precedence over the other?

Adjust Windows Size
When I click on this the window does adjust in size but I don't understand what determines what size it adjusts to or what the purpose is compared to just adjusting the window size manually (by grabbing the window borders).

Any clarification would be much appreciated. Thanks.

[scottgus1]

Scaled Mode vs Auto-resize Guest Display:
These both affect how the VM OS is displayed when the VM's "container" window is resized.

When Auto-resize Guest Display is checked, and Guest Additions are installed, dragging the edges of the VM's window will resize the OS's screen size inside the VM to whatever the window's viewing space is. The actual numbers in the OS screen size setting will change, and shapes in the OS will not distort. If you change the screen size in the OS's screen size settings, the VM window will automatically resize too.

Auto-resize Guest Display requires Guest Additions, and is disabled when Guest Additions are not installed. When no Guest Additions are installed, resizing the VM window either puts a gray border around the OS screen when the window is too big or puts scroll bars when the window is too small.

Scaled Mode can operate whether Guest Additions are installed or not. The screen size of the OS at the time that Scaled Mode is entered remains unchanged, and the pixels "scale" proportionately to the VM window size. Shapes in the VM's OS will distort. If you change the screen size in the OS's screen size settings, the VM window will not resize, and the distortion will adjust. The VM window's menu disappears when in Scaled Mode, so you have to remember the Host key & C key combination to get out of Scaled Mode.

Adjust Window Size:
Adjust Window Size only works when Guest Additions are not installed. When the gray border or scroll bars are showing because the VM window does not match the OS's screen size, Adjust Window Size will change the size of the VM window so its viewing size is the same as the OS's screen size. so no border or scroll bars are needed.

[fth0]

FWIW, there's a bit of documentation in Resizing the Machine's Window. It implicitly answers your precedence question by the ordering of the bullet points. To sum it up a bit:

When you change the size of the VM's window by dragging a corner, one of multiple things can happen:

1. If Scaled Mode is enabled, VirtualBox does not notify the guest OS and scales the virtual display so that it fits into the window.

2. If Auto-resize Guest Display is enabled and the VirtualBox Guest Additions are installed in the guest OS, VirtualBox notifies the guest OS so that it can adapt its display resolution to match the window size.

3. Otherwise, VirtualBox does not change the displayed contents so that the VM's window gets either white borders or scroll bars. If you want to adjust the window size to the virtual display again, the menu action is easier than to manually resize the window back to the exact pixel size.

[ozaz]

@scottgus1, @fth0,

Thanks a lot. That clarified things for me.

@scottgus1 - regarding the bit you wrote under "adjust window size". This seems to work even with guest additions installed as long as I have neither scaled mode, nor auto-resize guest display enabled, which seems to go along with what @fth0 wrote.

[scottgus1]

@scottgus1 - regarding the bit you wrote under "adjust window size". This seems to work even with guest additions installed as long as I have neither scaled mode, nor auto-resize guest display enabled, which seems to go along with what @fth0 wrote.

Correct. If Auto-resize Guest Display is unchecked, that disables all the display integration stuff, and makes the VM window act like Guest Additions isn't installed, for display adjustment purposes.