With the recent posts inquiring about *.chan files and Terragen, I've cleaned up a tool that I've been using for myself in Houdini to get cam data into Terragen. As long as you use it in a non-commercial way it should be fine to use with the free Houdini Apprentice. The tool itself is pretty straight forward to use without any real Houdini knowledge required. Knowing how to animate a camera in another package will stand you in good stead, however. There's a few things in the tool which I was toying with which don't really work, so just ignore them - the main functionality works well though.
I've also created a video demoing the tool's usage and how to do basic camera animation in Houdini. If you sign-up at Vimeo you'll have the option to d/l the video, otherwise it's only available to view as streamed content. It's available in both low-res and HD (113MB / 38min). The low-res version is pretty illegible so HD viewing is recommended.
I forgot to say in the video that you can click the help icon in the top right portion of the tool's parameters pane to view its documentation. Also, I wrongly said that the channel file extension should be chn when I meant to say chan - hopefully that was self-evident though. :)
Download Houdini Apprentice - http://www.sidefx.com/index.php?option=com_content&task=view&id=589&Itemid=221
Download the tool - http://www.sidefx.com/exchange/info.php?fileid=485&versionid=485
View or d/l the demo video - http://www.vimeo.com/831399
Thanks Moose, this is really helpful and appreciated. :)
- Oshyan
N.P.
Version 2 uploaded to the SideFX Exchange to account for chan export now working with path based animation (oops :-[).
Thanks :) Great news Moose. So is Houdini an easy package to use and understand? My background is Lightwave so do you think it would be easy enough to use just for setting up Camera motions?
Richard
Thanks, Moose. This interesting and helpful.
Quote from: cyphyr on March 28, 2008, 07:54:30 AM
Thanks :) Great news Moose. So is Houdini an easy package to use and understand? My background is Lightwave so do you think it would be easy enough to use just for setting up Camera motions?
Richard
Yeah, if you're only interested in animating a camera, there's hardly any learning curve at all. Don't know if you had a chance to look at the video, but in it I show a little camera animation how-to that should be sufficient to get something going with. That, along with the relevant page in the docs, should be all that's needed. The tool itself is very top-level so you wont have to go digging around in Houdini's innards - you don't have to
learn Houdini per se, is what I mean. :)
Great tutorial. Thanks!
Cheers :)
Now's probably a good time to say that as of Houdini 9.5 (currently in Public Beta release), chan export in Apprentice is now handled by the bclipnc format (Houdini's new binary non-commercial clip file), so the tool in this thread wont work anymore unless you're using Master or Escape. I'm not sure if the same applies for Apprentice HD, but I'd imagine it would seeing as it's also non-commercial (I'll check for sure next week when I upgrade).
So the method in the video will no longer work?
Not with H9.5 onwards, nah.
We really need the ability to do this within Terragen. Matt, add handles to our path points please so we can draw some damned curves.
Moose, Have you verified that your tool doesn't work in the new version?
Quote from: gregsandor on July 02, 2008, 06:50:29 AM
Moose, Have you verified that your tool doesn't work in the new version?
Apprentice (free) and Apprentice HD ($99) both use the non-commercial format for chan files as of Houdini 9.5. This means that you cant use the tool with these editions. Using Houdini Master or Escape should be unaffected though.
The tool should still work with a version of Apprentice 9.1 though...
Is 9.1 available for downlaod anywhere? I found only 9.5.
Quote from: gregsandor on July 02, 2008, 09:53:55 AM
Is 9.1 available for downlaod anywhere? I found only 9.5.
Yup, from the Downloads menu of the main site. :)
Thanks!
I can only see the 9.5 download...
Are you logged in? I believe you need to be logged in first.
That was it. I have version 9.1.244 now.
I'm at the point of displaying the terrain files after converting them; so far everything is going well, except the terrain tiles don't display.
Does my initial terrain file have to be started at lower left? My 513 x 513 .ter (40470m square) is centered at 0,0,0.
When I run the conversion, this is the result: I see in the video that there is some caching going on that isn't reported in my file:edit: solved
After success with converting the default generated heightfield I tried again the .ter, once more it only exports 9 files and some of them are narrow strips. I'll try a different terrain file.
It's been a while since I've used it... but I think I had it set up so that it converts the terrain geometry based on the dimensions of the default hf in TG (basically it's a bit of a cop-out hack and makes some assumptions - anything more and it would have been beyond my skills).
I've found though, that you can still get enough detail from using an oexr image of the hf displaced as geometry in Houdini rather than converting the actual lwo geo from TG if that's giving problems.
Maybe its the size of my terrain -- 40470 m. Ill try again with a 1000 m terrain and see how that goes. By the way thanks for the video tut -- its the clearest explanation of any tutorial ever.
I made a new terrain 1000px x 1000px, 10,000 m square and that worked. Then I found the setting for proxy terrrain size -- I think that would allow changes to the size -- I modified the default size and the terrain size changed. Would there be any trouble animating on a different size terrain? I don't know, I'll test when I have time. Meanwhile I also wonder whether it is necessary to even use the .lwo export method: can we jsut use an .exr on the proxy terrain?
So far I am able to get my camera to follow a path through the canyon. When I exported a .chan, there was only one line of data in it. Every time a bit more progress.
Originally, when I first created the tool I was unable to use the exr image as a 'final' mesh as either 1/ TG2 didn't have a "Flatten surface first" option (meaning a real mesh and a hf of that mesh would never match-up), or 2/ It did, and I just didn't see it :'(. So I was using the exr image as a 'rough' approximation for quick navigation (in Houdini) and as a guide for dicing up the lwo geo into manageable chunks.
But yes, you're right - I don't see much need to use the lwo geometry now. Also, depending on what you're doing, the LWO micro exporter route could be desirable (but like I said in the video, you'd need to use another piece of s/w to convert it into a format such as .obj that Houdini can read... Blender does a good job).
Not sure what the prob is with the chan export - if you cant figure it and wish to post a test-file, I'll take a look.
For the terrain I already have a .ter file I wish to use. The .exr or .lwo is only to guide the path creation. I thought maybe there was some way that Houdini used the terrain in calculating the output, but I don't think so.
One UI question: after the part of your video wher you first show how to select the handles on the camera ( I got that part) you somehow are able to click the button to move in the world and your camera controls are still visible -- when I click it they disappear. How?
As for the .chan export I will make another run at it this morning and post the result.
Thanks again for this tool and the tutorial -- its excellent.
Hey Moose,
GREAT TOOL!!! I have been using it for a project that would have been very hard to get done otherwise.
Thanks a LOT!!!
Hey I have to - don't ask why :P - get the created channel file back into Houdini and animate a Houdini Cam through it.
I basically know how to do this through chops and tried to reverse-engineer the chop network, which kinda works, but unfortunately not exactly. When I use the reversed channels to drive the camera the camera will be animated with some sort of offset and the lookAt isn't right either. I did fix most of this problem by (additionally to driving it through the CHOPS system) setting the camera to the originally used path as well as the old lookAtobject. After doing this it comes pretty close, however it isn't a hundred percent accurate (which I'll be able to fix in post) and at two points in the animation the camera tilts strangely for some reason.
I also tried to reconvert the chan files using excel and the functions specified but am running into issues there as well
(e.g. the script seems to calculate 1.5E-07 or something similar in the rotation values where they should be zero).
From what I could see the initial conversion does the following:
t x = -(x) + (TerrainSize set in e.g. proxyTerrain)
t y = x
t z = -(x)
r x = x
r y = 180 + x
r z = x
(I don't need to worry about the FOV for now)
is this right or did I miss something?
Have you had any experience with reversing the procedure as I am trying to do?
thanks a lot for your help
rodpacker
Quote from: rodpacker1 on June 02, 2009, 03:11:26 AMHey I have to - don't ask why :P - get the created channel file back into Houdini and animate a Houdini Cam through it.
Hi rodpacker1
It's been a while since I've had anything to do with this so my memory is really quite hazy with it all (It doesn't help that it was all quite spaghetti-like under the hood too). To be honest, anything with orientations send my head spinning (pun very much intended!), as whatever I end up with is pretty much through trial and error.
Just thinking out loud though, could you not use the original Houdini camera (the one used to create the chan file from), parent that to a fresh camera and apply any secondary animation/offsets to that - or am I not understanding what you want?
Hi Moose,
thanks for your quick reply.
Yeah that's the problem the camera info in the Houdini file used to render the animation in Terragen got lost so if I don't want to rerender everything in TG I need to reverse engineer the cam translation in CHOPS :)
I'm close though :)
thanks rodpacker
feel free to PM me if you need any Houdini help...
Hi goldfarb
Nice to see you around here. :)
Moose! You're one to talk. Where have you been? ;D
I didn't plan for it... but other things now take up my time leaving no real room for CG (Terragen or Houdini) - but I still enjoy looking-in on what people are producing, of course. :)
It was good to hear from you. I've always found your contributions to be very helpful. Hope you can still work in CG as much as you desire.
Hi Michael/Goldfarb,
thanks a lot for the offer to help. It looks like I have figured it out myself now and it looks like that if the original camera had a "lookat" set you will have to put that in the CHOPS driven cam again as well otherwise the rotation values will be offset.
Also for the last bit I was mentioning in my initial question where the camera was banking wierd, all I had to do was set the "look at UpVector" to "Use quaternions" and it seems like it's solved now. I am pretty certain the initial camera didn't have that set so I am quite surprised.
Either way that worked for me.
Again thanks for your offer to help mate!
Highly appreciated
rodpacker
glad it's working...
12 hours to learn Houdini (the learning one) enough to get an animation chan out of it, recon its possible ...?
The issues seem to be (across the various anim packages) that the further you get from the origin (0,0,0) the more the position data is "rounded". This makes for bad animation far from 0,0,0. Oh well back to the drawing board.....
richard
camera animation in Houdini is very easy...
there are tutorials at SESI, 3DBuzz, DigitalTutors and others...and if you've used LightWave you'll have no troubles getting the hang of it...
yeah, far from 0,0,0 things will always get a little tricky - it's a precision error, in Houdini (depending in the scale you're using) anything ~100,000 units and you'll see rounding errors. this is true of just about any application...
there are tricks you can use to get around it but I'm not familiar enough with animating the camera in Terragen to offer any right now...a cool one would be to be able to rotate a planet then you could just animate in Y and the rx/ry/rz :)
Quote from: goldfarb on June 19, 2009, 05:29:30 PM
yeah, far from 0,0,0 things will always get a little tricky - it's a precision error, in Houdini (depending in the scale you're using) anything ~100,000 units and you'll see rounding errors. this is true of just about any application...
So the animation I have been trying to achieve for the past 2 years is basically impossible. hmmm
I know it makes sense to shave precision of an objects movement when its a long way from the origin but if (as is my situation) your animation starts way off planet, next to another object also way off planet and follows that object in to the planet to more normal animation parameters then is there not a solution to this that avoids multiple renders and tricks and compositing etc...?
Quote from: goldfarb on June 19, 2009, 05:29:30 PM
...a cool one would be to be able to rotate a planet then you could just animate in Y and the rx/ry/rz :)
Pretty sure you can now...
richard
Richard,
highly depending on your scene of course, but would proportional down scaling be a possible option to move everything closer to the origin?
Just an idea
cheers
rodpacker
Hmm no it wont, thanks tho, it has given me an idea oddly ::)
Terragens ability to place a sphere in the same place relative to the camera might prove a way forward.
Its not that the number rounding happens at large distances that is the problem, its that it happens differently for objects at slightly different locations so it becomes "challenging" to animate two (or more) objects following similar paths.
More soon, (soon as I get replacement KB) ::) ;D
?Richard?
Hmm no it wont, thanks tho, it has given me an idea oddly ::)
Terragens ability to place a sphere in the same place relative to the camera might prove a way forward.
Its not that the number rounding happens at large distances that is the problem, its that it happens differently for objects at slightly different locations so it becomes "challenging" to animate two (or more) objects following similar paths.
More soon, (soon as I get replacement KB) ::) ;D
?Richard?
Quote from: cyphyr on June 19, 2009, 05:50:50 PM
Quote from: goldfarb on June 19, 2009, 05:29:30 PM
...a cool one would be to be able to rotate a planet then you could just animate in Y and the rx/ry/rz :)
Pretty sure you can now...
richard
nah, just cheched and you cant, dont know what the Planet Objects Heading, Elevation and Distance fields are for then...