# Algorithm What is the mathematical explanation behind this implementation of simulating eyeballs roll in eyes?

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Posted (edited)

I want to simulate eyeballs roll in eyes and I have found and forked this implementation in codepen.io. This is exactly what I need.

Smart way but I don't understand why it needs to work like this way. Why is it using ratioX and ratioY which are calculated from dividing mouseX and mouseY with their sum?  Is there a simpler or even cleverer way to do similar simulation?

Edited by caymanbruce

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Posted (edited)

I think they are using the x/y ratio as a cheap way to do fake trigonometry. If the mouse is far away from the eyes, they should rotate slower. If the mouse is close to the eyes, it will rotate faster. That would happen naturally with sin/cos. So I think what they have is already pretty simple and clever.

Edited by missionctrl

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Hello,
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I am using ZLib to compress and decompress all json but it doesn't work. I am now encoding it in base64 to avoid some issues but that doesn't change a thing.
I currently stopped trying to send the data and I am writing it in a file from the client and trying to read the file and decompress on the server side.
When the server is trying to decompress it I get an error from ZLib : zlib error: iostream error
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I cannot really configure anything on the server side (because boost has its ZLib compressor) and I don't know what is wrong with the decompression.
Any idea ?
rXp

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