www.nathanfx.com

Tutorial

Reseting Toxik/Autodesk Composite Preferences

Toxik or should I say Composite saves out allot of the user experience to its preference file. This is great if you like it a certain way. But with All the ways you could change something that you cant figure how to put back…this could have you up a wall trying to figure out what went wrong.

For those of you frustrated compositors here is the quick fix you been craving.

For example for OSX Toxik 2011 Users:
/Users/*Username*/Documents/toxik/’2011′/Default.txproject

It is to be notied for you Studio artist you can inter changeable save out your preferences and link to them with in the project preferences.

With in the UI you can find it under
Edit/ Project Preferences, Under the first tab that is displayed the Information tab


3DEqualizer Alt Key OSX fix

Anyone who uses 3DEqualizer on OSX knows that it runs through X11, And to its credit it runs pretty smoothly.

But there are a few issues with X11 that break the software right out of the box for some OSX users.

One is the ALT key.

support on at www.sci-d-vis.com tells mac users to download and install and open source version of x11, but is there a simple fix to this keyboard calamity?

Turns out Francis North an InkScape user noticed the same setbacks in Inkcape.

He writes in a form post http://www.inkscapeforum.com/viewtopic.php?t=800&f=5

1
Launch X11 from Applications/Utilities

2
Open the preferences window and enable the “Use the system keyboard layout” preference. This will force X11 to use it’s system default keyboard layout.

3
Open an xterm window (Command-N) and perform the following:

$ xmodmap -pke > ~/.Xmodmap

This captures the current xmodmap settings to a hidden file located in your home directory. It’s this ~/.Xmodmap file that X11 will by default use to override any system mappings.

4
Edit your .Xmodmap file by typing the following in the same xterm window:

$ open -e ~/.Xmodmap

Change the line: “keycode 66 = Mode_switch” to “keycode 66 = Meta_L”
Change the line: “keycode 69 = Mode_switch” to “keycode 69 = Meta_R”

Save the file and exit TextEdit.

5
Disable the X11 preferences “Emulate three button mouse” and “Use the system keyboard layout”, then close the preferences window.

These settings basically say “don’t treat ALT as a special key, and don’t override my .Xmodmaps file with system defaults”.

6
Close the X11 preferences window, any opened xterm windows, and then the X11 application.

That’s it. Now when you launch Inkscape, the ALT key should work as expected, and the status-bar will correctly display any ALT-key-specific help when that key is pressed (e.g. when using the Selection tool).

One final note: from an xterm window, you can debug your key mappings by typing “xev”. This program will open an interactive test window that will echo information about current key/mouse presses, and is a handy utility for determining keycodes and what they’re currently mapped to.

Feel free to provide any feedback and/or request for further clarification.

Happy ALT-keying

Thanks Francis North  for this InkScape Tip. 3D Equalizer MAC Users will also be thrilled to find out this fixes their Alt Key woes as well.

Nathaniel Westveer – www.nathanfx.com


Camera Solved 3D RotoPainting – Nuke

From an earlier entry, I gave away how to bake projection into Geometry/Cards to do paint fixes on them.  Nuke as powerful as it is has quite a few bugs..or more likely wasn’t designed around painting in the projection shader.  You Can do a blend Matte to combined projection but, add a roto paint and suddenly the scale blows way off..even if you reformat the input.  Its kind of Pesky if you want to use a camera solve to make paint fixes a bit easier.

There is a way I found out, not the sleekest one yet effective.  For the sake of example, Lets save you have a wall from shoot covered in cracks that have to be animated forming, this plate also has a shifting gradient from a light source in the shot.  Using a Camera Tracker you solved a 3d camera and its at your disposal.  Place a Card where the wall. For the Texture use a Rotopaint with an empty constant the format of your comp.  Then Attach the Bg1 to your Plate as you use the clone source from your clone tool, With a life time of of your choosing.  Then from the Scanline from the camera Merge this on top of the original Plate again. and vaula your paint fixes has as all the transforms. rotations and perspective shifts that you need. Create that Clean plate.

Nathaniel Westveer – www.nathanfx.com


You solved it!…now what – Exporting Nuke Cameras to .MA

Well blogging about tid bits about nuke has seemed to been quite the theme for me these last couple months,  I recently had run into a job where the only tracker I had at my hand inside nuke,  No problem I thought I’ve exported cameras before. but ..to my horror it can be very difficult some times.  Sure there are a lot of Mel and Python scripts to Maya, but none of them where playing nice with the version I was  using.  And most of what you get when you look for alternative ways are people telling you to upgrade to the newest Nuke which exports .FBX –  which was kind of an issue for me, one I didn’t have that version and two FBXs are very difficult them to play nice most of the time.

So is there a way to get Nuke to write out a .MA file Nativity, with a slightly crude yet very effective plug in, absolutely ( cue up following link in a new window or tab)

http://www.creativecrash.com/nuke/downloads/scripts-plugins/camera/c/nuke-camera-tracker-export

After installing this into your plugin folder ( make sure you but the base.ma into the icons folder)

createMayaScene Gizmo takes a bit to get use too, After attaching all of the handles you still have to Type in the names of the nodes into the 3 fields with Correct syntax.  (Example Read1 ,CameraTracker3 ect)

Once you do fill in the fields you are ready to export that camera to  .ma, pick the extension you want to save to and remember to put .ma after the file name and hit export and kick back for those brief .2-.3 secs as it writes out the file.

Open it in Maya and there you go, you Made it. And your co workers will be so impressed.

Nathan – www.nathanfx.com


3D in 2D (xy to xyz and back agin)

Nukes has a great 3d environment along with solid 2d node based composting, these tools can seem to live in different worlds. On one side, 3d the other 2D. Getting things out into 2d from 3d can like a daunting task if your not familiar with The reconcile 3d node. Lets Take the Godrays node for an example.  allot of the times the point you want to project from is not on a plane of parallax visible in the plate, more a point in 3d Space off in the distance.  You can animate it by hand but, if you can solve a camera its easier than you think.

So fire up nuke and hit that tab key as you type in R-e-c-o .. to pull up the the node like a pro.

You’ll notice that there is a few handles that are attached with it.  Img, Camera, Axis.  The most important of the handles to focus on right now is the Axis, where it observed by the solved(or animated) camera is where its going to back out the X,Y coordinates.  Click and drag the axis and orientate it in space where you want you ( for this example) god rays to project from and attach the other handles to assigned names,  Now from this you’ll have a few choices.

You can hit calculate key frames to have the computer look through the camera and give you the x,y values and bake it out. or you can have it update in real time and link an expression (apple drag, sorry windows folks i can only tell you from a mac at this moment) to the x,y transforms to the parenting node.

Either way  this node is amazingly simple to use for all you xy converts.

The Reverse Process – Points to 3D (from xy to xyz)

Now you say hey Nate that’s great But I need to translate a point in 2d to 3D.  This process can be done a few ways, what comes to mind is placing things in by hand, not a difficult process, in most cases but The foundry has your back with a node specialized to do this –  Points to 3d.  The min you get this node on screen you quickly observe that is has a camera handle like Reconcile 3D and relatively its the same process, take your solved or animated camera and attach it to it.  From there you notice in the node option s it has Point A, Point B, Point C.  These are the 3 Points you need to feed into the node to find the point in 3d space. So scrub through your timeline where you see your object, space or thing(er mo bob) and set the 3 points on 3 different frames,  and voila there you have it.  Your 2d values mapped out in 3D space.

Nathaniel Westveer – Nathanfx.com