Camera pan with a "look at" constraint

   21719   18   3
User Avatar
Member
219 posts
Joined: Oct. 2015
Offline
Hello,
Probably a newbie question…

When I set a “look at” constraint on my camera, how can I well pan and navigate with my “look at” target ?
Here is what I get (cf. screenshot).

I would like to only move pivot with camera when I pan on viewport.

Any idea ?
Thank you

Attachments:
screenshot_CameraNavigation.mp4 (2.4 MB)

User Avatar
Member
121 posts
Joined: Feb. 2014
Offline
That's freaky…. I was just about to ask the exact same thing. Either that or a feature request for a softimage style camera with aim.

+1 on this from me.

A>
User Avatar
Member
8041 posts
Joined: Sept. 2011
Offline
I'm not sure what you are after. The camera is constrained, so the rotate channels are overridden. When you move the camera to a new position, even if interactively the view direction changes, the constraint will reset the view direction based on the constrained direction. It looks like you might be after some kind of “two-way” constraint, where the constrained location is translated interactively by moving the camera. Such an operation is not feature of the constraint tools. It would be possible to design such a tool, the scripting operations make pretty much anything possible. Such a tool would have to dynamically disable the constraint, update the look-at location by querying the viewer, and re-enabling the constraint. Feel free the request such a tool if you think it would enhance your workflow. You may not actually need a constraint if all you want to do is interact with the camera by adjusting a look-at target interactively. The built-in camera handle works this way when not viewing through the camera.
User Avatar
Member
219 posts
Joined: Oct. 2015
Offline
Hello @jsmack,
Thank you for your explanation.

Yes, that would be a tool that dynamically disable the constraint, update the look-at location by querying the viewer, and re-enabling the constrain.
Is it doable ? How can I dynamically detect a pan viewer interaction within my camera ?
User Avatar
Member
174 posts
Joined: March 2014
Offline
@julca,
Houdini build in camera contain a temporary “look-at” with special handles, that's not exactly like in Softimage where this look-at is a reel null and the camera doesn't have any particular controlers in the viewport.
I found it working just fine in most anim cases.
Then, if needed, for now you can try the wonderfull QL camera rig ;-)
User Avatar
Member
219 posts
Joined: Oct. 2015
Offline
Hi @NNois !

I'll check that, and also see if with time the defaults handles suit me.
User Avatar
Staff
1081 posts
Joined: July 2005
Offline
Houdini 17 will have a new option to continuously export the view changes to the camera so you don't get that snapping back to your camera interest on mouse release. This option effectively just applies the constraint after each processed mouse motion to give a smooth motion. I don't know whether this specifically addresses your particular problem, but I thought I'd mention it.
User Avatar
Member
219 posts
Joined: Oct. 2015
Offline
Thank you for your feedback @Ondrej !
If I understand correctly, if I set a “look at” target constraint to my camera and pane in viewport, my camera will constantly facing target during operation.
What I ask for when I started this thread, is the possibility to pan with the “look at” target constraint moving in synchronization.

Anyway for now I use the defaults handle which give me good controls.
User Avatar
Member
121 posts
Joined: Feb. 2014
Offline
I'm having to move my camera and aim null in a front/side/top view to get the camera to do what I want. The default setup of having to rotate the camera to get it to point at an object is a pain especially if your camera is moving all over the place and the object you're interested is also moving around. If I don't set up an aim null then my perspective camera will orbit around some arbitrary point in space rather than a specific point in space. Being able to lock down a point in space that the camera is looking at AND move the camera around with the ease of view tools is what I and i think Julca are after.


cheers,

A>
User Avatar
Member
382 posts
Joined: Nov. 2010
Offline
Bumping this up.
The camera in H is probably the second most important reason why I don't use H as much as I want.
Once you get used to a target cam and find out how fast it it to work with and set up smooth rotations, not to mention manual matchmoving or alignment, the H cam feels like a relic from the last century.
Due to the nature of the lookat constraint it is not really helpful to build a target camera, since it just overrides but not exposes the calculated rotation to the local axis which means the local alignment of the gizmo is always the same as the world alignment, making it impossible to “dolly” along the cams z axis for example.
However it is good to see that work is being done. Looking forward to 17.
User Avatar
Member
918 posts
Joined: March 2014
Offline
Ondrej
Houdini 17 will have a new option to continuously export the view changes to the camera so you don't get that snapping back to your camera interest on mouse release. This option effectively just applies the constraint after each processed mouse motion to give a smooth motion. I don't know whether this specifically addresses your particular problem, but I thought I'd mention it.

Hello Ondrej,

did this ever make it into H17? If so, I have a hard time finding it.

Thank you
Andy
User Avatar
Member
1 posts
Joined: Jan. 2015
Offline
Andy58
Ondrej
Houdini 17 will have a new option to continuously export the view changes to the camera so you don't get that snapping back to your camera interest on mouse release. This option effectively just applies the constraint after each processed mouse motion to give a smooth motion. I don't know whether this specifically addresses your particular problem, but I thought I'd mention it.

Hello Ondrej,

did this ever make it into H17? If so, I have a hard time finding it.

Thank you
Andy


Hey,

I think he's referring to option:



Once enabled, you no longer get that “snapping back to the look-at” on MouseRelease, but instead it will update the constrain every update.

PS: Hi! :-D

Attachments:
Screenshot at 2018-10-29 15-13-47.png (35.1 KB)

User Avatar
Staff
128 posts
Joined: Jan. 2012
Offline
Andy58
Ondrej
Houdini 17 will have a new option to continuously export the view changes to the camera so you don't get that snapping back to your camera interest on mouse release. This option effectively just applies the constraint after each processed mouse motion to give a smooth motion. I don't know whether this specifically addresses your particular problem, but I thought I'd mention it.

Hello Ondrej,

did this ever make it into H17? If so, I have a hard time finding it.

Thank you
Andy

Hi,

In the viewport, under the camera menu ( The icon which says ‘no cam’ by default ), there is an option near the bottom of the menu called ‘Export View Continuously’. This is the feature that Ondrej had mentioned previously.

Hope it helps!

Cheers,
Scott
Senior Product Designer
Side Effects Software
User Avatar
Member
121 posts
Joined: Feb. 2014
Offline
Sadly this isn't what I (we) were hoping for.

The request is for a camera rig with a physical interest null that works with the view tools

The behaviour would be:

That the camera always orbits around the interest null.
When using the view track/pan tool the interest null gets translated the same as the camera so the camera rotation remains the same.
When using spacebar+f to frame an object the interest null gets moved to the centre of the object you are framing up.

cheers,

Andi.
User Avatar
Member
6 posts
Joined: July 2015
Offline
Hey! I have submitted an RfE (#92554) on this topic. Let's see if something happens
User Avatar
Member
121 posts
Joined: Feb. 2014
Offline
Any news of this RFE #92554 ?… Now i'm using houdini for real the camera is a real pain for sweeping moves. I either use the stock camera and put up with not being able to keep the camera pointed at an object, or i use a look at null and then can't use the view tools which is utterly cack handed….. I know you can control the universe with houdini but I just want a nice smooth camera move…
User Avatar
Member
35 posts
Joined: Oct. 2008
Offline
Have you guys tried Qlibs tool's camera rig. With this camera rig its possible to pan and tilt camera while having a look at constraint. But you can animate these parameers as sliders but not while being in camera view. Hope it helps!
User Avatar
Member
121 posts
Joined: Feb. 2014
Offline
Hi RamaKrishna,

interesting set of tools.. but sadly it's the “while in the camera view” that's the crucial bit.



cheers,

Andi.
User Avatar
Member
75 posts
Joined: Feb. 2017
Offline
I see it's H18 almost 18.5 in 2020 and the camera aim viewport behavior is still stuck in the 90s.

The export view continuously is a nice addition, but it doesn't address the fundamental flaws with the camera system as it stands. As others have mentioned in this thread, having a look at point that is respected in the viewport, while manipulating the camera from the viewport is of the utmost importance for working with cameras in Houdini in an efficient manner. I have literally spent all day today animating a camera move that would have taken me an hour with a “Maya like camera and aim setup.” I hate comparing packages, especially to Maya these days, but I think it's what everyone is wishing for in this regard.

It would be really nice to see some improvement in this area in upcoming releases.

Edit: I didn't realize this was in the SI users section, but my issues still stand! I'll make a new post in a different section as well.
Edited by smbell - Aug. 14, 2020 17:24:57
  • Quick Links