Modeling an accurate joint morph

arm bend

Over the last week I have had to learn how to create joint morphs. My thanks to Shaun Lee Bishop for finally showing me the light.

1. Model the joint and skelegons in modeler. Make weight maps for each bone. Make sure the weight maps do not overlap and are set to 100% on each point. If the weight maps have the same names as the skelegons then they will be applied automatically when the corresponding bones are created in Layout.

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2. Send object to Layout. Convert skelegons to bones. This command is located on the Setup tab Add menu.

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3. Bend one bone using only one rotation axis. Write down the bend angle because you need this information latter in the process.

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Make sure that all the points are being controlled 100% by their bones. For me the mesh controlled by the upper bone was being influenced by the lower bone. I am not sure why that was but checking Use Weight Map Only fixed it.

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4. Choose Save Endomorph from the File menu to create a new morph. Then choose Save All Objects to add the endomorph to the object on disk.

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5. Switch back to modeler and the object should update to include the morph. View the morph by clicking the M in the lower right of the Modeler window and then pick the morph from the popup menu. You should see the mesh in its bent form. Remodel this morph to the shape you want when the bone is bent.

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6. When done choose save object and switch back to Layout. The object should update to include the remodeled morph. To see the morph in layout open the Objects Properties panel and click the deform tab. Add the Morph Mixer displacement plugin from the popup list at the bottom of the panel Double click Morph Mixer to open up its properties. Move the slider to 100%. In the image below the joint is now folded completely in half. This is because the bone is still rotated.

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7. Now to make a new morph that removes the bend but keeps the remodeled shape you just have to bend the bone in the opposite direction from the original bend. In the example the bone was bent 90 degrees so we enter –90 in the heading field.

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8. Select the object and save a new endomorph. Also choose Save All Objects to update the object on disk. We now have an endomorph that should deform correctly when the bone is bent.

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9. In the object properties panel turn off the Morph Mixer plugin. We were just using this to create the morph. Add the Joint Morph Plus plugin from the popup menu at the bottom of the Deform tab. Double click this to open the settings panel.

At the top of the panel select the bone to control the morph.

Select the axis angle that will control the morph.

Check Value1. The default is to have the base shape when the bone is not rotated, which is what we want in this case.

Check Value2 and enter the angle that the morph will be at 100%. Also choose the morph to use.

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That is it. If all went well the morph should now be functioning.

bend gif

-Joe Lertola
12/19/2009