Well,
this is simply a demo by AMC-Verlag (author = Rainer Kothe) or something to play around with. Press "Select" key (or was it Option key?) and you will see the screen flicker strangely, well this is no bug, but the gfx are now real 3D - however you need red-green glasses, just like in "Superski" (also by AMC-Verlag) to see the real 3D effect.

AMC (or their hardware label Portronic) once sold hardware named "Multipad" and "Powerpad" which consisted of a joypad and a paddle. This demo program makes some use of it, you can use the paddle to change the viewing angle of the picture and you can use the joystick (at the same time!) to move the man (named birdman)...