I have no idea how it differs from the original version (as shipped in
the SDK).  :-)

The original version just didn't work and i ported a C-version (google
it) into Java. And this seems to work for my app and other developers'
apps.

On Feb 5, 11:22 pm, Tim Newsham <[email protected]> wrote:
> Could you explain how your version might differ from the original
> version?
> The version in the standard library:
>
>    computes M = (Projection x Model)^-1
>    puts world into a homogenous vector V,
>       with x/y coordinates mapped from screen coords to -1.0 to 1.0
>       and z coordinate mapped from (0,1) to (-1,1)
>       w coordinate set t 1
>    multiplies MxV, with the resulting w coordinate normalized to 1.0
>    returns that value
>
> I implemented my own version (based on the C GLU library code) and
> got substantially the same results (differences less than 1/100th %
> off)
>
> On Feb 5, 5:40 pm, Streets Of Boston <[email protected]> wrote:
>
>
>
> > I found issues with the gluUnProject as well.
> > I wrote a new one for my own app (The Gube) and it works very well. I
> > use gluUnproject for tracking 2D finger-touches and flings into the 3D
> > model-view/space.
>
> > You can do a gluUnproject search on this forum and you will find 
> > this:http://groups.google.com/group/android-developers/browse_frm/thread/9...
>
> > Go to message# 8, which contiains the source control.
>
> > On Feb 5, 7:18 pm, Tim Newsham <[email protected]> wrote:
>
> > > Hi, I'm having problems with gluUnProject. I saw other discussions on
> > > this message base regarding this function and they did not solve my
> > > problem. When I use GLU.gluUnProject I get values that are close, but
> > > not quite right. I'm manually keeping track of my model matrix and I
> > > replicate the projection matrix manually.  (I have also tried setting
> > > the projection matrix to identity and manually incorporating a
> > > projection matrix into my model matrix, and I ended up with the same
> > > results). I tried using the builtin GLU.gluUnProject function and I
> > > also implemented my own based on reading that source and reading the C
> > > GLU sources and both seemed to give substantially similar results.
>
> > > So I put together a small demo, trying to keep it as minimal as
> > > possible and still get the point across.  Either this demo shows a
> > > misunderstanding I have of gluUnProject or it shows a bug in the
> > > function or opengl projections. Can someone check this over and see if
> > > I'm just doing something wrong or if there's a bug that needs to be
> > > filed?
>
> > > The files are here:http://www.thenewsh.com/~newsham/unproj/
> > > In particular:
>
> > >     unproj.java         - full source to example
> > >     unproj-debug.apk    - resulting apk file
> > >     unproj              - directory with full ant-buildable project
> > >     unproj.zip          - zip of directory
>
> > > Tim- Hide quoted text -
>
> - Show quoted text -

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