Q: How exactly does the Virtual Preview module work?

A: Please read on for more information

The Responsive Virtual Preview module (RVP) was made to get an impression about how a wall would look like if a painting hangs on the wall. That means it simulates different paintings are hanging on the wall, so you can get a preview of it before actually hanging the painting to the real wall.

The technical part:

First you need a image of your wall on which you want to virtually 'hang' your paintings. Next you need some images of paintings within a directory of your website.
Once configured, you can publish your module in the frontend - now the module does the 'real' work, it takes the wall-image and renders each painting-image into it. So finally, you get some pictures of your wall with your pictures rendered into. In the frontend, you can switch between the different images by clicking the small painting images below the main image - the main image will then switch to the image with the respective paintinf rendered into.