How to make a plane alway upright to the camara

[avid]

I want to do a animation which have a lot of trees.
so , I have to use texture to make the tree. I want
to know how to make to plane which has the tree
texture alway upright to the camara when the camara
moveing in the animation. thanks .

[joojaa]

use image planes they alwas face the camera tough...

Or getthe camera up and rotate accordingly (but you might need some spesific constraints like this point is always planted against ground or it only pivots in xz directions)

[k_dub]

you could maybe use sprites...it's under the particle menu (an option for the type of particle you want)...If I'm not mistaken, you can use your tree image. Sprites are like planes that always face the camera...and you can have several of them (since your scene has a lot of trees). There should be information in the maya tutorials...so, check it out.

[harywilke]

if you are makeing a bunch of trees for a flythrough animation, just make some poly or nurbs planes and orient constraint them in the Y axis to the camera. (select camera, shift select plane, constrain/orient [] and choose Y axis)

[goggle]

I'm sorry, what's the trick to constrain only one axis? When I hit the constraint option box I only get options for weighting and add/remove.
I can think of a few ways to do this indirectly but it'd be so much easier to just constrain to one axis

-James

[harywilke]

my bad i should have tested it before i posted. you have to break the connections for the aim constraint in the x and z axis after applying the constraint.
try this. select the control object(camera), shift select the controled object(Tree Plane). apply an aim constraint. (set the aim vector to the direction of the face of the tree, default is along the positive Xaxis) then select the Tree Plane in the channel box break connections on the x and z axis. (select the x and z axis names in the channel box and right click over them to bring up the menu with break connections) this will leave them aim constrained only on the Y axis. you will have to go back and re zero the x and z axis rotations when you are done.
hope that helps

[goggle]

Ah ha. should've thought of that myself.
You have to break things in order to get them to work :-7

Thanks.

-James