how to create colour inversion on overlapping figures?

[fanbrahms]

hello everyone, i have encountered a problem with a task that I cannot undestand how to decide- tried searching similair requests but to no satisfying resolution. if anyone knows how to do this please share, I would much appreciate it. 

The artwork is by an unknown artist, I do not own it. It is here merely for visual exmple of what I amtrying to achieve, which is black&white colour inversion in the overlapping shapes and figures...

Thanks

[Monika Gause]

This is a destructive approach:

If there are strokes in your artwork, outline them. Then select all and make a compound path. Select the "Even odd" fill rule in the attributes panel.

[Monika Gause]

It can also be made non-destructive.

Draw all the shapes. If a shape should have just a stroke or even is an open path, then apply Effect > Path> Outline stroke

Then group everything (also the background rectangle)

Apply Effect > Pathfinder > Exclude

[Ton Frederiks]

Create a layer and fill it with a black object.

Create a layer above it for your artwork.

Make a shape with a white fill and stroke.

In the Appearance panel click the arrow for the fill and stroke and set the opacity blend mode to Difference.

Create a Graphic Style with this object selected.

Make sure that New Art Has Basic Appearance is unchecked in the Appearance panel menu.

Start drawing with the Graphic style active.

[SJRiegel]

Tom -- that works if your docuemnt mode space is RGB. For it to work in CMYK mode, the background box has to be set to Registration - which is no good if the piece will be printed.

[Ton Frederiks]

Yes, for printing on a press you need some more steps:

Select All

Flatten Transparency

Edit > Edit Colors > Convert to Grayscale

File > Document Color Mode > CMYK

(which can be made into an action)