Dennis Pierce (dpierce++at++dolphin.orlando.sgi.com)
Mon, 30 Sep 1996 06:58:14 -0400
I am confused. I personally have answered this question in quite a
bit of detail at least one time, and I think I have seen others do
the same. When you write that you have asked this question 3 times
and have not gotten a response, I think either we don't understand
what you are asking, or you don't understand what we are answering.
Ok, so here's another try...
You are correct in stating that a 2D entity does not map into a
3D world; however, it is possible to extend the 2D mouse by assigning
one of the buttons to the third dimension. This is EXACTLY what
perfly does but it performs the assignment for the DCS attached to
the world, not a model. If you want to perform the "spin" function
to a model in the world and not the DCS of the world itself, you will
need to attach a DCS above the model's geometry in the scene graph.
So, once again, if you want to use a mouse to manipulate a 3D
model, you have the mouse's x and y motion but need to assign a
button to z so that when you push the button, either x or y or
both x and y are used for z. So, no button, you're moving in x and
y. With button, you're moving in z. Rotation? Simply use another
button to assign rotational meaning to the x and y mouse motions.
Perfly does this!
In closing, if this is not the answer you're looking for then I really
don't understand the question.
As always, good luck on your project!
On Sep 30, 11:04, Lae Hyun Kim wrote:
> Subject: Screen Coords -> 3D Coords
> --
> Hi all!
>
> Please Help me. This mail is 3 times.
>
> I have some problem.
> I'm trying to manupulate a 3d object picked by mouse like a manupulator
> in Inventor.
> The problem is that the 2D mouse position doesn't translate to a single
> point in 3D space.
> I tried to use a trackball manipulator(xformer) to the object's DCS
> matrix but position of 3d object is not matching with position of mouse.
>
> Your answer would be greatly appreciated.
>
> Regards,
>
> KIM.
>
> ===================================================
>
> Lae-Hyun Kim,
> Korea Institute of Science and Technogy, CAD/CAM.
> E-mail : dochi++at++chopin.kist.re.kr
> URL : http://chopin.kist.re.kr/dochi/dochi.html
>
> /////
> ++at++ ++at++
> -----------------------ooO-(_)-Ooo-----------------
> =======================================================================
> List Archives, FAQ, FTP: http://www.sgi.com/Technology/Performer/
> Submissions: info-performer++at++sgi.com
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>-- End of excerpt from Lae Hyun Kim
---- Dennis Pierce SGI / Ste 130 / 900 Winderley PL / Maitland FL 32751work : 407.660.0073 vmail: 800.326.1020 x58548 ======================================================================= List Archives, FAQ, FTP: http://www.sgi.com/Technology/Performer/ Submissions: info-performer++at++sgi.com Admin. requests: info-performer-request++at++sgi.com
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