Maya

Houdini to Maya (BGEO import/export)

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I found this maya plugin that seems to work reasonably well for importing a BGEO sequence from Sidefx Houdini into Autodesk Maya.

You can download the plugin from here: http://www.houdinistuff.com/

The instructions provided in the readme file can be a bit confusing.  Here are the steps I used to successfully load a Bgeo sequence from houdini:

  1. Save the bgeo.mll file into your plugins folder and load it in maya.
    mbeo_maya_plugin
  2. Open the command line editor and run: mBgeoReader
    mbgeo_maya_script_editor
  3. This will create a new poly object called mBgeoReader. Check in the outliner window.
    mbgeo_maya_outliner
  4. Select the object and go to the attribute editor.
    mbeo_maya_attribute_editor
  5. Enter the Path to the bgeo files.
    mbeo_maya_bgeo_path
  6. Done. You can pan through the timeline to see the animation sequence.

I haven’t yet tried exporting a Bgeo sequence from Maya, but the import worked successfully. Some problems that you may run into are attributes like velocity that aren’t  transferred into the Maya scene. At least I haven’t been able to during my test run. If there is a way, let me know. Without the velocity attribute, I wasn’t able to produce an accurate motion blur in Maya.

It may be a good idea to turn off any attributes in Houdini before using the ROP output node to create the bgeo sequence. This should increase performance in Maya. Lastly, use the geometry cacheing in Maya to speed things up if needed.

Render WIREFRAME in Maya with Mental Ray

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There are a few ways to render objects as wireframes in Maya. The first is to use the toon/Vector shader, but this method doesn’t work very well with non-polygon surfaces like nurbs. After some research, I found that contour rendering with mentalray works better and is much faster. This process also requires that you convert nurbs surfaces to polygons, but its a small nuance. You can use render layers in Maya and just add the duplicate objects there, instead of affecting the entire scene.

These instructions are for Maya 8.0 and above.

1. Make sure you have the Mental Ray plugin loaded.

If not, go to Window -> Settings/Preferences->Plug-in Manager
Then enable Mayatomr.dll

2. Create/Select your objects. I’m just using a polygon sphere.

3. Optional: Create a new render layer and add the objects here.

2. Apply a background shader to the object.

Use these settings:

Specular Color: black
Reflectivity: 0.000
Reflection Limit: 0
Shadow Mask: 0
Matte Opacity Mode: solid matte
Matte Opacity: 1

3. In the attribute editor view of the background shader above, select the right arrow at the top to go into the SHADING GROUP.

4. Now, in the attribute editor view of your Shading Group, expand the mental ray section. Then expand the Contours section.

Check ‘Enable Contour Rendering‘

5. Set the values for Color, Alpha, and Width. Color is the color of the wireframe lines. Alpha controls transparency of the lines. Width is the thickness of the lines.

I used these values:

Color: white
Alpha: 1
Absolute Width
Width: 0.5

6. Open the render globals window and go to the mental ray tab.

Expand the Contours section.
Expand the Contours->General section.
Check ‘Enable Contour Rendering’.

Expand the Contours->Quality section.
Set Over-sample to 3 (Higher values create smoother lines)

Expand the Contours->Draw Contours section.

Check ‘Around All Poly Faces’

Here is a wireframe screenshot using the Mental Ray contour line method above:

Here is an alternate method (toon/Vector shader) for generating wireframes in Maya:

[youtube]http://www.youtube.com/watch?v=UONmeh24xh4[/youtube]

UV Layout

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While in my advanced texture and lighting class during this summer, I came across an amazing UV unwrapping program called UV Layout by Headus. Unlike Maya, which has limited tools for doing UVs, not to mention the time it takes, UV Layout is fast, and far easier. It can read OBJ files and saves the UV maps into a new file or the existing one. You can then use Maya to transfer the UVs:

  1. Select the imported object with new UV maps
  2. Shift select the destination object in the maya to copy to.
  3. Set the Menu to Polygons
  4. Select Mesh
  5. Select Copy Transfer Attributes
  6. Select UV Maps to transfer
  7. Apply

The Headus website has very good video tutorials as well.