Above versus below: Object covers other object
The property "Object covers other object" detects whether an object covers at least the same area taken by some other object underneath it, regardless whether the upper object is opaque and thus makes the object underneath it invisible, or not.
The configuration options for a check based on the "Object covers other object" property can be seen below.
The "Consider" option defines the set of objects for which it shall be determined which of these objects covers at least one other object from the set of objects defined by "Check against".
The example and exercise below make use of the check Object covers other object(s).kfpx and the PDF files one red square covered by a transparent green circle.pdf and one red square covered by an opaque green circle.pdf which are available for download:
In the example shown below, the green circle (set to be transparent) in the center is detected, as it fully "covers" the red rectangle below it, and is on top of that red recangle.
In the example shown below, the green circle (set to be opaque) in the center is detected, as it fully "covers" the red rectangle below it, and is on top of that red recangle.