[osg-users] Get current Billboard ModelView matrix?

[Robert Osfield]

Hi Phillip,

On 30 June 2016 at 12:22, Philipp Meyer <philipp.meyer at fh-bielefeld.de> wrote:
> unfortunately some objects move in my scene, so its not enough to only hold the old view matrix.
>
> The camera AND any object can move.

OK.

You haven't ever said what you are trying to do with current vs
previous frame data.  I don't recall anyone ask for this specific
requirement before.  The OSG community have been around quite a long
time now...  So you are either doing something very novel or a trying
to solve a common problem in a very awkward way.

One thing to also considering in your pondering is that not all
objects will actually be in the view frustum over subsequent frames,
especially as you pan around, new objects will appear in the view
frustum for the first time so won't have a previous modelview matrix
associated with them.

Since you haven't said what this is all in aid of I can't say whether
this later issue has any baring, it will however, if you really need
to do what you say you need to do will introduce it's own set of
issues.


Robert.