<div dir="ltr"><div><div>Thanks for your reply John, but the shape is not the same for all the pinholes (same volume, different shape), as they need to focus on different parts of the object.<br><br></div>My main issue is on how to define the theta and phi angles of the generic trapezoid. Also, is there a way to mirror a volume?<br> <br>Meanwhile I found this presentation:<br><a href="http://ipnweb.in2p3.fr/~detect/publications/meeting_step_gdml_geant4_23032010.pdf">http://ipnweb.in2p3.fr/~detect/publications/meeting_step_gdml_geant4_23032010.pdf</a><br> which really helped me understand what each parameter of the generic trapezoid meant, so I'll share it with you GATE users.<br><br></div>Regards, <br></div><div class="gmail_extra"><br clear="all"><div>Débora Salvado</div> <br><br><div class="gmail_quote">2014-05-27 18:24 GMT+01:00 John Apostolakis <span dir="ltr"><<a href="mailto:John.Apostolakis@cern.ch" target="_blank">John.Apostolakis@cern.ch</a>></span>:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div style="word-wrap:break-word"> <div>I am not sure if this will help:</div> <div><br> </div> <div>If all your pinholes are the same shape (or can be created by subtracting the same "generic trapezoid" shape from the bigger shape) then in Geant4 at least you only need to define one 'solid'.</div> <div><br> </div> <div>Then you subtract it multiple times, with each copy positioned at a different location and/or with a different orientation. ( The orientation will be governed by the rotation matrix and the translation that you give it.)</div> <div><br> </div> <div>I hope that I understood your issue - or that someone else can add the specialised GATE knowledge necessary to give better advice.</div> <div><br> </div> <div>Regards,</div> <div><span style="border-collapse:separate;color:rgb(0,0,0);font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:-webkit-auto;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;font-size:medium"><span style="border-collapse:separate;color:rgb(0,0,0);font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:-webkit-auto;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;font-size:medium"> <div style="word-wrap:break-word"> <span style="border-collapse:separate;color:rgb(0,0,0);font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:-webkit-auto;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;font-size:medium"> <div style="word-wrap:break-word"> <span style="border-collapse:separate;color:rgb(0,0,0);font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:-webkit-auto;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;font-size:medium"> <div style="word-wrap:break-word"> <span style="border-collapse:separate;color:rgb(0,0,0);font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:-webkit-auto;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;font-size:medium"> <div style="word-wrap:break-word"> <span style="border-collapse:separate;color:rgb(0,0,0);font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:-webkit-auto;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;font-size:medium"> <div style="word-wrap:break-word"> <div> <div>John</div> <div> <div> <div><span style="border-collapse:separate;color:rgb(0,0,0);font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:-webkit-auto;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;font-size:medium"><span style="border-collapse:separate;color:rgb(0,0,0);font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:-webkit-auto;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;font-size:medium"> <div style="word-wrap:break-word"> <div> <div>===================================================</div><div><div class="h5"> <div><br> </div> <div>On May 27, 2014, at 5:50 PM, Débora Salvado wrote:</div> </div></div></div> </div> </span></span></div> </div> </div> </div> </div> </span></div> </span></div> </span></div> </span></div> </span></span></div> <div><br> <blockquote type="cite"><div><div class="h5"> <div dir="ltr"> <div> <div> <div> <div>Dear GATE users,<br> <br> </div> I'm trying to use the "generic trapezoid" volume to define a multi-pinhole collimator, with each pinhole focusing different parts of the FOV.<br> </div> <div>Consider the following set-up:<br> <br> /gate/world/daughters/name trap1<br> /gate/world/daughters/insert trap<br> /gate/trap1/geometry/setDx1 26. mm<br> /gate/trap1/geometry/setDx2 26. mm<br> /gate/trap1/geometry/setDz 5. mm<br> /gate/trap1/geometry/setTheta 0. deg<br> /gate/trap1/geometry/setDy1 26. mm<br> /gate/trap1/geometry/setDy2 21. mm<br> /gate/trap1/geometry/setDx3 21. mm<br> /gate/trap1/geometry/setDx4 21. mm<br> /gate/trap1/geometry/setPhi 90. deg<br> /gate/trap1/geometry/setAlp1 0. deg<br> /gate/trap1/geometry/setAlp2 0. deg<br> /gate/trap1/setMaterial Air<br> /gate/trap1/placement/setTranslation 0. 0. 0. mm<br> <br> </div> When I change the "theta" parameter, the face at +pDz goes up or down in the Y direction.<br> </div> How can I make that same face move in the X direction (right or left)?<br> </div> I tried to modify the phi/Alp1/Alp2 parameters, but the visualization either stays the same or it gives me an error...<br> <div> <div><br> </div> <div>Thank you in advance, <br> <br clear="all"> </div> <div> <div> <div> <div> <div>Debora Salvado</div> </div> </div> </div> </div> </div> </div></div></div> _______________________________________________<br> Gate-users mailing list<br> <a href="mailto:Gate-users@lists.opengatecollaboration.org" target="_blank">Gate-users@lists.opengatecollaboration.org</a><br> <a href="http://lists.opengatecollaboration.org/mailman/listinfo/gate-users" target="_blank">http://lists.opengatecollaboration.org/mailman/listinfo/gate-users</a></blockquote> </div> <br> </div> </blockquote></div><br></div>