Hi Kim (and Jean-Sebastien), Kim Bale <kcb...@googlemail.com> wrote: > Hi Jan, > > My apologies for not replying earlier, I haven't been checking > osg-users as much as I possibly should have. It appears that I've > missed quite a few osgOcean posts.
No problem :)
>
> >> BTW, is there a reason why is the size of the screen hardwired to
> >> 1024x768? Do the shaders expect this? Or why is it so? It took me a
> >> while to figure out why it doesn't draw correctly on our wall.
>
> J-S pretty much answered this one- the screen resolution is only
> required for setting up the FBOs involved in the fullscreen effects.
> However, this can be changed using:
>
> /** Sets the current screen size, needed to initialise the God Ray and
> DOF frame buffers.
> * Default is 1024x768.
> */
> inline void OceanScene::setScreenDims( osg::Vec2s size ){
> _screenDims = size;
> _isDirty = true;
> }
Ah, OK - I have missed this function. I saw that the variables are initialized
in the constructors but that there wasn't a way to pass new screen dimension
to them (would be a good addition to the constructor, IMO).
> Setting that will cause the FBO textures to be resized and rebound at
> the desired resolution on the next pass of the update visitor. You
> could easily bind this function to a callback which calls it when the
> screen resolution changes.
Good, that will help. I more-or-less need to call this only on setup, but at
least it saves me hacking in an extra constructor.
>
>
> Back to the original problem with collision detection. As J-S said,
> direct access to the vertices is not currently supported. However you
> should be able to get access to the geometry by adding some simple
> accessors. To be honest I haven't thought about collision detection
> much as it wasn't an original requirement for me, but I can see that
> it would be a valuable addition and i'll try and give you some
> pointers.
What I need is rather simple - I need an object to bob on the surface of the
waves, so basically I just need the current height at a given x,y position.
<...>
> Like I say I haven't thought about collision detection much, but my
> initial thoughts are that you could use the bounding boxes of the
> mipmap geometries as a quick way to find the patch in which the
> collision occurs and the test the triangles within that patch. The
> animation, of course complicates things somewhat. If you're planning
> on doing accurate collision detection you should be able to get access
> all the vertices involved for the frames at the current LOD from the
> _mipmapData container.
I think that is even an overkill for me - I just need the height to be able to
attach an object to the surface of the wave. But thanks for the pointers, I am
going to have a closer look at it today.
Regards,
Jan
signature.asc
Description: This is a digitally signed message part.
_______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
