I will quote someone here:
QUOTE (Hongkun Wang):
"Hi , Dave Yazel
Thanks for your help.
I already resolve the trees rendering. I am using:
(1) Put all trees in a OrderedGroup, and use SharedGroup to save memory.
(2) Figure out all trees according 'Z' coordinate in viewplatform coordinate
SYS. We can use matrix (Tv1.Tv2....Tvm)-1 . (T1.T2....Tn) to transform the
object coordinate into viewplatform coordinate.
Swap the Transform3D of all trees (NOT swap the child themself, since all my
trees are completely same, so, swapping Transform3D is very fast!)
(3) Adjust Transform3D for all trees in order to perform 'Billboard'
behavior. (We can not use OrientedShape, there is a serious bug.)
Actually, the method 'p1.distance(p2) ' is not efficient for this case,
since we need the distance along 'Z' axis, but not between the object and
viewplatform.
Best Regards.
Hongkun Wang
....END QUOTE
Perhaps this is the "serious bug" he is refering to in oriented shapes?
Dave
> ----------
> From: J. Lee Dixon[SMTP:[EMAIL PROTECTED]]
> Reply To: Discussion list for Java 3D API
> Sent: Tuesday, September 19, 2000 11:20 AM
> To: [EMAIL PROTECTED]
> Subject: [JAVA3D] Billboard using Z-axis
>
> I'm playing with using BillBoard... whenever I set the
>
> bb.setAlignmentAxis(0f, 0f, 1f )
>
> to select the Z-axis, the object DISAPPEARS. If I take the axis a
> LITTLE off the Z:
> float D = 0.001f;
> bb.setAlignmentAxis( 0f, D, Math.sqrt(1f - D*D) );
>
> It works fine. What's wrong with using EXACTLY the z-axis?? Using x- or
> y-axis works. Anybody else see this?
>
> -Lee
>
> J. Lee Dixon
> Software Engineer
> SAIC - Celebration, FL
> [EMAIL PROTECTED]
>
> ==========================================================================
> =
> 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".
