Re: [osg-users] KDTree Picking (at an angle)
Robert,
I think I know why things go bad in KDTree,
I'm using KDTree to spoof the location of some actual geometry, which is
transformed in a vertex/geometry shader.
So, I compute a bounding box for where the geometry ought to be, and create
a dummy geometry from that - I then compute the KDTree for this dummy
geometry, and assign it to the actual geometry that will be sent down the
pipe, which is at the scene origin, not its final location.
When the line-segment intersector goes to pick, it first checks to see if
the line segment intersects the bounding box of the drawable, which as far
as I can tell is computed against the actual geometry (in this case the
geometry at the origin) and not the KDTree's bounding box. When it doesn't
properly intersect, the line-segment intersector returns without hitting the
KDTree.
I think what is needed is to test against the KDTree bounding box, rather
than the geometry bounding box, if a KDTree is assigned.
Does this make any sense?
sean
On Wed, Dec 3, 2008 at 10:05 AM, Sean Spicer [EMAIL PROTECTED] wrote:
Robert,
I will see if I can repro the problem with osgpick and send you the osg
file. It may take me a week or two though as I've got a lot on my plate ;-)
cheers,
sean
On Wed, Dec 3, 2008 at 3:28 AM, Robert Osfield [EMAIL PROTECTED]wrote:
Hi Sean,
This sounds like a bug, but without a dataset and example that
reproduces the problem it's next to impossible to home in on a fix.
Would it be possible for you to provide a problem dataset that
illustrates the problem? If it can be reproduced with one of the
existing examples like osgpick then this will make it easier to track
down.
Robert.
On Wed, Dec 3, 2008 at 12:00 AM, Sean Spicer [EMAIL PROTECTED]
wrote:
Hi Gang,
I'm working on improving picking performance via KDTree, but I'm hitting
an
issue that is driving me nuts: If I pick a node from directly above
(e.g. +
Z axis) everything works great, and picking is *very* fast. If I pick
at an
angle, (e.g. from eye(1,1,1)) then picking is fast, but not accurate -
nodes
to the left, right, top, or bottom get picked instead of what I'm after.
Here is my KDTree Build function:
#ifdef USE_KDTREE
// Update the KDTree
osg::KdTree::BuildOptions kdTreeBuildOptions;
osg::ref_ptrosg::KdTree kdTree = new osg::KdTree();
if(kdTree-build(kdTreeBuildOptions, geometry))
{
geometry-setShape(kdTree.get());
}
else
{
LOG_MSG(logERROR) osg::KdTree::build() unsuccessful.;
}
#endif
Any suggestions?
cheers,
sean
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] KDTree Picking (at an angle)
Hi Sean,
Yes this makes sense. There is a mechanism in Drawable that allows
you to define an inital bound that is used in the compute of the
geometry position, this was done quite a few years ago at begining of
the journey in the land of vertex shader. These days I think a better
solution would be to just allow users to manually define it and
disable the automatic compute of the bounding volume.
So try using
geometry-setInitialBound(bb);
Where bb is the max size you expect the goemetry to get to/or the
bound that you used for the KdTree.
If that works OK I can look at cleaning up the overriding of the computed bound.
Robert.
On Thu, Dec 4, 2008 at 6:30 PM, Sean Spicer [EMAIL PROTECTED] wrote:
Robert,
I think I know why things go bad in KDTree,
I'm using KDTree to spoof the location of some actual geometry, which is
transformed in a vertex/geometry shader.
So, I compute a bounding box for where the geometry ought to be, and create
a dummy geometry from that - I then compute the KDTree for this dummy
geometry, and assign it to the actual geometry that will be sent down the
pipe, which is at the scene origin, not its final location.
When the line-segment intersector goes to pick, it first checks to see if
the line segment intersects the bounding box of the drawable, which as far
as I can tell is computed against the actual geometry (in this case the
geometry at the origin) and not the KDTree's bounding box. When it doesn't
properly intersect, the line-segment intersector returns without hitting the
KDTree.
I think what is needed is to test against the KDTree bounding box, rather
than the geometry bounding box, if a KDTree is assigned.
Does this make any sense?
sean
On Wed, Dec 3, 2008 at 10:05 AM, Sean Spicer [EMAIL PROTECTED] wrote:
Robert,
I will see if I can repro the problem with osgpick and send you the osg
file. It may take me a week or two though as I've got a lot on my plate ;-)
cheers,
sean
On Wed, Dec 3, 2008 at 3:28 AM, Robert Osfield [EMAIL PROTECTED]
wrote:
Hi Sean,
This sounds like a bug, but without a dataset and example that
reproduces the problem it's next to impossible to home in on a fix.
Would it be possible for you to provide a problem dataset that
illustrates the problem? If it can be reproduced with one of the
existing examples like osgpick then this will make it easier to track
down.
Robert.
On Wed, Dec 3, 2008 at 12:00 AM, Sean Spicer [EMAIL PROTECTED]
wrote:
Hi Gang,
I'm working on improving picking performance via KDTree, but I'm
hitting an
issue that is driving me nuts: If I pick a node from directly above
(e.g. +
Z axis) everything works great, and picking is *very* fast. If I pick
at an
angle, (e.g. from eye(1,1,1)) then picking is fast, but not accurate -
nodes
to the left, right, top, or bottom get picked instead of what I'm
after.
Here is my KDTree Build function:
#ifdef USE_KDTREE
// Update the KDTree
osg::KdTree::BuildOptions kdTreeBuildOptions;
osg::ref_ptrosg::KdTree kdTree = new osg::KdTree();
if(kdTree-build(kdTreeBuildOptions, geometry))
{
geometry-setShape(kdTree.get());
}
else
{
LOG_MSG(logERROR) osg::KdTree::build() unsuccessful.;
}
#endif
Any suggestions?
cheers,
sean
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] KDTree Picking (at an angle)
Will do, and I'll report back...
sean
On Thu, Dec 4, 2008 at 1:07 PM, Robert Osfield [EMAIL PROTECTED]wrote:
Hi Sean,
Yes this makes sense. There is a mechanism in Drawable that allows
you to define an inital bound that is used in the compute of the
geometry position, this was done quite a few years ago at begining of
the journey in the land of vertex shader. These days I think a better
solution would be to just allow users to manually define it and
disable the automatic compute of the bounding volume.
So try using
geometry-setInitialBound(bb);
Where bb is the max size you expect the goemetry to get to/or the
bound that you used for the KdTree.
If that works OK I can look at cleaning up the overriding of the computed
bound.
Robert.
On Thu, Dec 4, 2008 at 6:30 PM, Sean Spicer [EMAIL PROTECTED]
wrote:
Robert,
I think I know why things go bad in KDTree,
I'm using KDTree to spoof the location of some actual geometry, which
is
transformed in a vertex/geometry shader.
So, I compute a bounding box for where the geometry ought to be, and
create
a dummy geometry from that - I then compute the KDTree for this dummy
geometry, and assign it to the actual geometry that will be sent down the
pipe, which is at the scene origin, not its final location.
When the line-segment intersector goes to pick, it first checks to see if
the line segment intersects the bounding box of the drawable, which as
far
as I can tell is computed against the actual geometry (in this case the
geometry at the origin) and not the KDTree's bounding box. When it
doesn't
properly intersect, the line-segment intersector returns without hitting
the
KDTree.
I think what is needed is to test against the KDTree bounding box, rather
than the geometry bounding box, if a KDTree is assigned.
Does this make any sense?
sean
On Wed, Dec 3, 2008 at 10:05 AM, Sean Spicer [EMAIL PROTECTED]
wrote:
Robert,
I will see if I can repro the problem with osgpick and send you the osg
file. It may take me a week or two though as I've got a lot on my plate
;-)
cheers,
sean
On Wed, Dec 3, 2008 at 3:28 AM, Robert Osfield
[EMAIL PROTECTED]
wrote:
Hi Sean,
This sounds like a bug, but without a dataset and example that
reproduces the problem it's next to impossible to home in on a fix.
Would it be possible for you to provide a problem dataset that
illustrates the problem? If it can be reproduced with one of the
existing examples like osgpick then this will make it easier to track
down.
Robert.
On Wed, Dec 3, 2008 at 12:00 AM, Sean Spicer [EMAIL PROTECTED]
wrote:
Hi Gang,
I'm working on improving picking performance via KDTree, but I'm
hitting an
issue that is driving me nuts: If I pick a node from directly above
(e.g. +
Z axis) everything works great, and picking is *very* fast. If I
pick
at an
angle, (e.g. from eye(1,1,1)) then picking is fast, but not accurate
-
nodes
to the left, right, top, or bottom get picked instead of what I'm
after.
Here is my KDTree Build function:
#ifdef USE_KDTREE
// Update the KDTree
osg::KdTree::BuildOptions kdTreeBuildOptions;
osg::ref_ptrosg::KdTree kdTree = new osg::KdTree();
if(kdTree-build(kdTreeBuildOptions, geometry))
{
geometry-setShape(kdTree.get());
}
else
{
LOG_MSG(logERROR) osg::KdTree::build() unsuccessful.;
}
#endif
Any suggestions?
cheers,
sean
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] KDTree Picking (at an angle)
Hi Sean,
This sounds like a bug, but without a dataset and example that
reproduces the problem it's next to impossible to home in on a fix.
Would it be possible for you to provide a problem dataset that
illustrates the problem? If it can be reproduced with one of the
existing examples like osgpick then this will make it easier to track
down.
Robert.
On Wed, Dec 3, 2008 at 12:00 AM, Sean Spicer [EMAIL PROTECTED] wrote:
Hi Gang,
I'm working on improving picking performance via KDTree, but I'm hitting an
issue that is driving me nuts: If I pick a node from directly above (e.g. +
Z axis) everything works great, and picking is *very* fast. If I pick at an
angle, (e.g. from eye(1,1,1)) then picking is fast, but not accurate - nodes
to the left, right, top, or bottom get picked instead of what I'm after.
Here is my KDTree Build function:
#ifdef USE_KDTREE
// Update the KDTree
osg::KdTree::BuildOptions kdTreeBuildOptions;
osg::ref_ptrosg::KdTree kdTree = new osg::KdTree();
if(kdTree-build(kdTreeBuildOptions, geometry))
{
geometry-setShape(kdTree.get());
}
else
{
LOG_MSG(logERROR) osg::KdTree::build() unsuccessful.;
}
#endif
Any suggestions?
cheers,
sean
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] KDTree Picking (at an angle)
Robert,
I will see if I can repro the problem with osgpick and send you the osg
file. It may take me a week or two though as I've got a lot on my plate ;-)
cheers,
sean
On Wed, Dec 3, 2008 at 3:28 AM, Robert Osfield [EMAIL PROTECTED]wrote:
Hi Sean,
This sounds like a bug, but without a dataset and example that
reproduces the problem it's next to impossible to home in on a fix.
Would it be possible for you to provide a problem dataset that
illustrates the problem? If it can be reproduced with one of the
existing examples like osgpick then this will make it easier to track
down.
Robert.
On Wed, Dec 3, 2008 at 12:00 AM, Sean Spicer [EMAIL PROTECTED]
wrote:
Hi Gang,
I'm working on improving picking performance via KDTree, but I'm hitting
an
issue that is driving me nuts: If I pick a node from directly above (e.g.
+
Z axis) everything works great, and picking is *very* fast. If I pick at
an
angle, (e.g. from eye(1,1,1)) then picking is fast, but not accurate -
nodes
to the left, right, top, or bottom get picked instead of what I'm after.
Here is my KDTree Build function:
#ifdef USE_KDTREE
// Update the KDTree
osg::KdTree::BuildOptions kdTreeBuildOptions;
osg::ref_ptrosg::KdTree kdTree = new osg::KdTree();
if(kdTree-build(kdTreeBuildOptions, geometry))
{
geometry-setShape(kdTree.get());
}
else
{
LOG_MSG(logERROR) osg::KdTree::build() unsuccessful.;
}
#endif
Any suggestions?
cheers,
sean
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] KDTree Picking (at an angle)
Hi Gang,
I'm working on improving picking performance via KDTree, but I'm hitting an
issue that is driving me nuts: If I pick a node from directly above (e.g. +
Z axis) everything works great, and picking is *very* fast. If I pick at an
angle, (e.g. from eye(1,1,1)) then picking is fast, but not accurate - nodes
to the left, right, top, or bottom get picked instead of what I'm after.
Here is my KDTree Build function:
#ifdef USE_KDTREE
// Update the KDTree
osg::KdTree::BuildOptions kdTreeBuildOptions;
osg::ref_ptrosg::KdTree kdTree = new osg::KdTree();
if(kdTree-build(kdTreeBuildOptions, geometry))
{
geometry-setShape(kdTree.get());
}
else
{
LOG_MSG(logERROR) osg::KdTree::build() unsuccessful.;
}
#endif
Any suggestions?
cheers,
sean
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
