Here is an example: Edit fiddle - JSFiddle - Code Playground, very simmillar to yours. Try to scroll the page a little and you will see offset, resulting incorrect raycasting. Same thing on your tshirt website.
Here is an example: Edit fiddle - JSFiddle - Code Playground, very simmillar to yours. Try to scroll the page a little and you will see offset, resulting incorrect raycasting. Same thing on your tshirt website.