Rosettes with mirror symmetry

The program for making rosettes offers many possibilities and it is difficult to find something to aim for. As a guide we can use symmetries. Mirror symmetry at the x-axis is a simple example. It makes that the image remains unchanged if we change the sign of φ. We use the mapping function of the last post. Because the cosine function is an even function and the sine function is an odd function we simply have to put all coefficients b and d of the mapping function equal to zero. This is a result with three-fold rotational symmetry:

yellowbutterfly

Here if have used a butterfly as input image. You can recognise some details of its wings and legs as well as parts of the yellow flower it sits on. The mirror symmetry makes that the image becomes more abstract. The mapping function is

function mapping(x,y){
 imageZero(x,y);
 imageAdd(0.7,0,0,0,1,6);
 imageAdd(0,0,1,0,2,3);
 imageAdd(0.5,0,0,0,2,12);
}

Make your own creations. This is easy: Load http://bookofgames.ch/rosette.html in your browser. Then download the html and JavaScript codes using those buttons. Open the downloaded html page in your browser and edit the JavaScript file in a text editor. Save your changes and reload the html page. Send a comment if you get stuck and need help or if you want to share your results.

This entry was posted in Anamorphosis, Kaleidoscopes and tagged , , , , . Bookmark the permalink.

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