Yes, you can fiddle with the field of view values and achieve a "zoom" effect. It's been well over a year since I did it but certainly it does work. Dave, I remember we were both goofing with this at the same time.
- John Wright Starfire Research David Yazel wrote: > > I realized after I sent this that my ramblings are probably not helpful. > Sorry if this created more confusion than clarity. > > dave > > ----- Original Message ----- > From: "David Yazel" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Saturday, May 11, 2002 2:22 PM > Subject: Re: [JAVA3D] Zoom without moving the Viewpoint > > Thats a good question. To answer it you need to consider what a view is > really doing. It is taking an image plate (your screen) and transforming > the 3d geometry so that it renders in the 2d space, perfectly matching your > screen, basically flattening the 3d. This transformation uses a projection > policy to determine they type of transformation that is happening. But if > your view is at position x,y,z and you are viewing a point at x'y'z' then > the distance from the view to the point is fastored into the "depth" of the > image. The width of the object you are looking at in virtual units will map > to some number of pixels on your screen. To zoom you are shortening the > distance between the object and the view. This means that other objects at > the edges of your scene leave the field of view and are lost. There are > only two ways to shorten the distance between the view and the object. > Either move the object or move the view. Now "moving the view" means > different things to different people. You could have the view at a certain > translation, but apply a scaling to the view. This actually does "move the > view" since the mapping from the image plate to the object changes, but it > still resides in the same translated state. I have never tried to scale a > view... but technically it should work. > > Dave Yazel > http://www.magicosm.net/ > > ----- Original Message ----- > From: "Pereira Sieso, Rafael" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Saturday, May 11, 2002 12:37 PM > Subject: [JAVA3D] Zoom without moving the Viewpoint > > Hello all: > I am new on developing in Java3D and I have found a problem when I want to > make a zoom of the scene. Is ther any way on Java3D for doing a zoom without > moving the position of the view point? > > Thank you in advance. > > Rafael Pereira. > > ----------------------------------------------------------------- > Este correo electr�nico y, en su caso, cualquier fichero anexo al mismo, > contiene informaci�n de car�cter confidencial exclusivamente dirigida a su > destinatario o destinatarios. Queda prohibida su divulgaci�n, copia o > distribuci�n a terceros sin la previa autorizaci�n escrita de Indra. En el > caso de haber recibido este correo electr�nico por error, se ruega > notif�quese inmediatamente esta circunstancia mediante reenv�o a la > direcci�n electr�nica del remitente. > ----------------------------------------------------------------- > The information in this e-mail and in any attachments is confidential and > solely for the attention and use of the named addressee(s). You are hereby > notified that any dissemination, distribution or copy of this communication > is prohibited without the prior written consent of Indra. If you have > received this communication in error, please, notify the sender by reply > e-mail. > ----------------------------------------------------------------- > > ========================= > To unsubscribe, send email to [EMAIL PROTECTED] and include in the body > of the message "signoff JAVA3D-INTEREST". For general help, send email to > [EMAIL PROTECTED] and include in the body of the message "help". > > =========================================================================== > To unsubscribe, send email to [EMAIL PROTECTED] and include in the body > of the message "signoff JAVA3D-INTEREST". For general help, send email to > [EMAIL PROTECTED] and include in the body of the message "help". > > =========================================================================== > To unsubscribe, send email to [EMAIL PROTECTED] and include in the body > of the message "signoff JAVA3D-INTEREST". For general help, send email to > [EMAIL PROTECTED] and include in the body of the message "help". =========================================================================== To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff JAVA3D-INTEREST". For general help, send email to [EMAIL PROTECTED] and include in the body of the message "help".
