Love it! Nice job! Did you think about using a render technique like the maps one? (render smaller square intead of all the screen multiple times)
Version 2 of FractalViewer will use Web Workers (multipple threads) to render the image, so it will resemble "the maps one" (rendering multiple smaller squares at once). See progress on this at https://github.com/valera-rozuvan/FractalViewer/issues/3 .
By the way - maybe I got your question wrong. What do you mean by "a render technique like the maps one"? Can you point me to a resource where it is described?