Advanced positoning/sizing allows you to have full control over the position and size of your elements. This is very powerful but also a lot more time-consuming than using FancyMenu's automated sizing and positioning.
To enable andvanced positioning/sizing for an element, right-click it and click on Advanced Positioning or Advanced Sizing.
The element will automatically switch to the advanced mode when you set an advanced position or size value.
To disable it and switch back to normal positioning/sizing, clear all positioning/sizing values.
While an element is in Advanced Sizing/Positioning mode, resizing and/or moving the element could be disabled or restricted.
The reason why advanced positioning/sizing is so powerful is that you can use placeholders in the position/size values.
This allows you to use the Calculator placeholder (located in the Advanced placeholder category) in combination with placeholders of the GUI category, like Screen Width, GUI Scale, Element Width and more.
You can add placeholders by clicking on the Placeholders button at the top-right side of the text editor. If you don't see this button, the content you want to edit does not support placeholders.
To calculate something with the Calculator placeholder, replace the example expression with your own. You can use nested placeholders in the expression, so you can make use of the screen size, element size, etc. placeholders there.
For example, this placeholder will simply solve 1 + 1 and will show as 2 later:
{"placeholder":"calc","values":{"expression":"1 + 1","decimal":"false"}}
The decimal variable is set to false, which is important for most sizing/positioning calculations, so just set this always to false when working with advanced positioning/sizing.
The following calculator uses the Screen Width placeholder and divides it by 2:
{"placeholder":"calc","values":{"expression":"{"placeholder":"guiwidth"} / 2","decimal":"false"}}