<html><body><div style="font-family: arial, helvetica, sans-serif; font-size: 12pt; color: #000000"><div>Dear Gate users,</div><div><br></div><div>Here is what, initially, I would like to code in Gate: my world contains a box with water and some nanoparticles. I want my source to be of the same size as one side of my box and I want it to irradiate the full box. I draw here the source in yellow :<br></div><div><br></div><div><img src="cid:5cb08ddb85b785a52cb0e8acea8665101c954d06@zimbra" data-mce-src="cid:5cb08ddb85b785a52cb0e8acea8665101c954d06@zimbra" width="351" height="337"></div><div><br></div><div>In fact, I want the yellow source to be a parallel beam. Does someone know how I can do that ?<br></div><div><br data-mce-bogus="1"></div><div>Many thanks for your help!<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>Sarah Blind<br data-mce-bogus="1"></div></div></body></html>