Christian
provided the right equations.
Here
is a ‘dirty way’ to bypass all the math:
-
when you pick an object with
the mouse, move a hidden plane object to the picking position and orient it so
that it’s perpendicular to the camera.
-
Then, while the mouse button is not
released, raycast (Ray Intersection BB) on the plane
from the camera position and through the current picking position. That gives
you the position picked on the plane. Move your object to that position.
The
nice thing about this solution is that it works for any plane (not only the
screen plane). You can move objects constrained on a wall or a floor, and so on…
Francois
-----Original
Message-----
From:
Sent: mardi 9 avril 2002
To: Kam Memarzia; '
Subject: RE: [Virtools] Moving
Objects using the mouse.
Hello,
Please
find the equations down there:
XYZ are 3D coords of a point IN
CAMERA REF
xy are screen coords as per the near clipping plane.
WH are width and height of the screen
then we have:
X=Z*tan(fov/2)*(2*x/W-1);//1
Y=Z*tan(fov/2)*(H-2*y)/W;//2
You need the object Z (picked
position) and transform it into the camera ref.
Then you position the object on a
plane perpendicular to the camera dir at Z,
using X,Y.
Best regards,
Christian Garnier.
-----Message d'origine-----
De :
owner-virtools-user-group@lists.theswapmeet.com [mailto:owner-virtools-user-group@lists.theswapmeet.com]De la part de Kam Memarzia
Envoyé : mardi 9 avril 2002
10:18
À : 'Virtools Mailing List'
Objet : [Virtools] Moving
Objects using the mouse.