*The following is not quite a research level question, but I still find this site appropriate for asking it. I hope I get it right here.*


I am preparing a talk for a general public and I want to discuss some hyperbolic geometry. I wish I had a good illustration device. I imagine a dynamical version of one of Escher's tessellations of the Poincare model (e.g the one in [How might M.C. Escher have designed his patterns?](https://mathoverflow.net/q/50872/89334)) which changes isometrically when I slide the computer mouse.


**Question:** Could you please make any recommendation regarding any device of a nature similar to the one I describe above?
In fact, I will be happy to have whatever interactive model of whatever geometry, not necessarily hyperbolic.


**Subquestion:** if you're kind enough to make a recommendation, could you also advice regarding copyright issues (if applicable)? 


**Sidequestion:** Any other recommendation regarding presentation of geometry will be appreciated. Please note that my concern is more about the quality of the presentation than the actual mathematical content...




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**UPDATE:** Thank you! I am thrilled to get in less than 24 hours so many excellent answers and comments. Fortunately, Arnaud Chéritat provided EXACTLY what I asked for, and I happily accept his answer. Indeed, I am going to use his tool for my presentation. However, there are other excellent tools here which could be useful elsewhere. It seems to me a good idea to keep collecting those and MOF is an excellent platform for that.


I suppose one should post one of these big-list questions which has a broader scope than this one (but not too broad), something like "Visualizing tools for lectures on geometry". I am not sure how this is done, so you can pick up the glove! 



Interactive model of the hyperbolic plane for a general public lecture
By chance I wrote, not long ago, the following applet (HTML5+JS+WebGL) that works at least on Firefox and Chrome.


<https://www.math.univ-toulouse.fr/~cheritat/AppletsDivers/Escher/>


This work is CC-BY-SA, including the code, but NOT the image by Escher, for which I have not asked permission: you can probably use it a few times in conferences (fair use) but not in a permanent publication (and I will eventually have to remove this image or to create a variant of my own, like Valdimir Bulatov).


