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
>__________________________________________________________
>
>===========================================================================
>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".
-- __________________________________________________________ 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 __________________________________________________________
