----- Original Message -----
Sent: Tuesday, May 02, 2000 2:32 PM
Subject: Re: [JAVA3D] Picking bug in
1.2Beta2
Right now, only BOUNDS and GEOMETRY picking works consistently.
However, if you only need to get terrain elevation, it is possible (and in
gaming almost always done this way) to create a height field data map from
which to get elevation data instead of actually doing segment collisions with
the terrain geometry. You would have to write the look-up code and data
table for your terrain however, as well as some type of interpolation
function. :-(
Other than that it's write your own Java3D polygon collision code (ouch!)
or wait for the fixes. :-(
Perhaps there is another collision solution for your app that doesn't
involve line segments and polygons. We made a terrain collision example for
GDC that was functionally defined, that is, there was a collision function
that defined an approximation to the terrain surface. i.e. Given X and Z, it
returns Y on the surface of the terrain.
Hope that helps a little.
Jason Stine wrote:
I have been having a similar problem. I
thought it was something simple
like setting bounds or using a PickRay
pointing the wrong direction. I went
from using the PickTool with
your OpenFlt loader to trying to make it work
with HelloUniverse - no
success at all. I'm trying to pick a location on
the ground
(terrain loaded with your OpenFlt loader) independent of the
mouse or
viewpoint, then get the elevation of the intersection point. When
I try to access the PickResult at runtime, I get a null pointer
exception
because there's nothing there. If you have any
suggestions at all I'd love
to hear them.
Jason
-----Original Message-----
From: Shawn Kendall
<[EMAIL PROTECTED]>
To: [EMAIL PROTECTED]
<[EMAIL PROTECTED]>
Date: Tuesday, May 02, 2000 11:34
AM
Subject: [JAVA3D] Picking bug in 1.2Beta2
>I have been having allot of trouble getting the PickTool to work
>correctly with our OpenFLT loader.
>I assumed that something
in the way the loader is building the scene was
>causing the PickTool
to fail when using GEOMETRY_INTERSECT_INFO. So I
>tried using
the PickTest code in our viewer on objects made in that from
>the
example code. After much testing, and then finally a quick test on
>the actual running PickTest demo, I can definitely see that
>GEOMETRY_INTERSECT_INFO collisions fail when it should return
>collisions. Let me clarify, the actual example demo
fails!
>
>I can set the demo to GEOMETRY_INTERSECT_INFO and
when I try to pick
>certain objects in the window (not the wireframe,
the regular polygons
>objects), sometimes it works on certain
areas and sometimes it does
>not. What's really strange is that
if I just set it back to GEOMETRY,
>the picking works and accurately
to the objects shape! This must mean
>that the picking routines
are different for GEOMETRY and
>GEOMETRY_INTERSECT_INFO, which I
would think are nearly the same (but of
>course that doesn't really
matter).
>
>Has this bug been posted, because it is not on the
BUGS/ISSUES page, and
>if so what is the status?
>Thanks
>
>--
>__________________________________________________________
>
>Shawn
Kendall
Full Sail Real World Education
>Course
Director
3300 University BLVD
>Real Time 3D for Gaming
Winter Park FL 32792
>[EMAIL PROTECTED] http://www.fullsail.com
>__________________________________________________________
>
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>
===========================================================================
To unsubscribe, send email to [EMAIL PROTECTED] and include in the
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send email to
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--
__________________________________________________________
Shawn Kendall Full Sail Real World Education
Course Director 3300 University BLVD
Real Time 3D for Gaming Winter Park FL 32792
[EMAIL PROTECTED] http://www.fullsail.com
__________________________________________________________
