The following use ray tracing to find image for a point light source in a glass filled with water.
The refraction of water is assume to  be 4/3 and the index refraction of glass is assumed to be 3/2.
Both of them can be modified with the sliders (index1 and index2).
yc is the location of the point source.

Click play (right triangle) to start the ray tracing.
You can drag the eye to find image at different viewing location. (Yes. it is depends on where you look at it).

translate strings in simulation to different language format before download
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Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop. This work is licensed under a Creative Commons Attribution 2.5 Taiwan License
Download EJS jar file(1061.8kB):double click downloaded file to run it. (22 times by 9 users) , Download EJS source View EJS source