Here is a collection of video-feedback loops generated within CindyJS. This setup was used for a demonstration at the Open Doors Day at Technical University of Munich 2016.
In order to run these examples you require a webcam that points to your screen. You might use an external screen and your internal webcam, a USB-connected camera or you can use your smartphone as webcam together with an app like DroidCam. Good results are obtained if you disable all automatic camera adjustments. On Linux this can be done with guvcview.
In most of the examples you can calibrate the initial transformation by pressing M, then moving the small white/yellow/purle/cyan point to the displayed image of the big small white/yellow/purle/cyan point resp. and switching back by pressing M again.
In those examples you can press C to toggle the code.
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