I am referring to the size of the window created in the Movie Render Queue pop-up window. This is a PIE session (in a new window), as, as far as I am aware, we do not intend to support the Movie Render Queue PIE Executor starting inside the Level Editor viewport - it is only intended to be used as a pop-up window. If you are using the runtime version of Movie Render Queue (ie: not using the Window > Cinematics > Movie Render Queue UI, but are instead triggering it after the game has started) then MRQ has no control over the actual viewport - it renders entirely to an off-screen texture, where the game’s viewport does not currently matter. Your use case is unusual and not something that MRQ would account for.
> LogMovieRenderPipeline: Expected size: 540 x 960 (Render Job Resolution)
> LogMovieRenderPipeline: Actual size: 544 x 960 (?)
> LogViewport: Scene viewport resized to 540x960, mode Windowed. (?)
This is not entirely expected, but also not unexpected. When creating textures on the GPU the GPU may decide to pad their sizes up to a 16 pixel alignment. So 540/16 = 33.75, which the GPU can’t represent, so it pads it up to 544 (16*34). So this part is not unexpected, MRQ is designed to handle this case and it instead takes only the top left 540x960 pixels out of the image, as the extra 4 pixels on the edge were never written to as they exist on the GPU texture, but were never written to.
What is a bit unexpected here is that you are seeing that warning, as the only place I see that prints it in code is a safety check after MRQ has supposedly handled it, and it not handling it at that point should have been fatal and caused the application to close. Do you have a minimal repro case that I can run that would cause this log to show up?
> Is this behavior expected? Is a small portion of the screen (bottom UI bar or window ) always reserved, making it impossible to hit full monitor resolution (even with full screen option checked)?
There are generally limitations in place to prevent the client from creating a window larger than their monitor, as this is usually a mistake (ie: the user has switched monitors since the last time they used the application) and if the application retained the original size it would prevent the user from being able to change it again.
There is a command line parameter, “-ForceRes” but it is not clear from looking at the code if this applies to the editor, it may only apply to the game mode. You could try launching the editor with “UnrealEditor.exe <path to uproject.uproject> -ForceRes -ResX=3840 -ResY=2160 -Windowed” and see if that allows subsequent PIE windows to get created at the full size (even though they would fall off the screen). If the editor does not support it, you may be able to make it work with “-game” mode, which would be: “UnrealEditor.exe <path to uproject.uproject> -game -ForceRes -ResX=3840 -ResY=2160 -Windowed”. This is not an ideal scenario - you would need to change how you invoke Movie Render Queue, and you may see small visual differences between rendering in the editor versus rendering in -game, but it is worth a shot to see if this gives you the requested window you need for your pixel points/object precision that you’re trying to calculate.
Otherwise, as stated earlier, you will need to debug the code to see where the clamp is coming from and possibly making an edit to the engine. This is an unusual use case and not something that the editor is designed to support.