Part 3: Half a Smile (Using Vertex Groups)
a tutorial by Calvin

In Part 2 of our tutorial, we created a Driver which made Mr. Ant Smile and "UnSmile."

Here is the Blend file so you can follow along: ant03.blend
As we dragged the "Happy" Bone up and down.

But what if we want to make Mr. Ant smile on the right side of his face but remain neutral on the other.

Well, you might say... lets just create two shape keys. One shape key that has the left side deformed, and one with right side.
Make sense but what if we already have a smile that we like?

That is where "VGroup" under Shapes Tab comes in. We can use the SAME shape key but tell the shape key what part of the face to deform.

But before we do that we need to tell Blender which side of our mouth is Left and which side is Right.
So under Shapes Tab, select our "Happy" Shape Key.


1) Click on Mr. Ant and go into Edit mode.
2) Select the Right side of Mr. Ant's Face. (Note: It is adviced to select only the right side of Mr. Ant's mouth.)


3) Create a New Vertex Group, Name is "Right" and assign the selected vertices.


4) Now select the Left side of Mr. Ant... Create a New Vertex Group, Name it "Left" and assign the seletecd vertices.


5) While still in "edit mode" look under the Shapes Tab. Rename the "Happy" Shape Key to "Happy.R" and tell it to use the "Right" Vertex Group.


6) Click "Add Shape Key" and apply the following settings:


7) Rename our Current Driver (Happy) to Happy.R and create a new one and call it "Happy.L"


8) Another cool thing we can do is move the Driver Bones to a "Convenient" location.


9) Click on Mr Ant, and go into the IPO Curve Editor.
- Notice that now we have a Happy.R ShapeKey and Happy.L ShapeKey.
- Click on the Happy.R Shape Key and tell it to use the Happy.R Driver Bone.
- You probabley noticed this, but I change the curve around, so that when the driver moves down (-1.0) the shape key comes close to 1.0, causing Mr. Ant to UnSmile. And while moving up (1.0) to smile even more.


Now that we have a curve that we like...
Click on the curve and locate the following button in the IPO Curve Tab.

The button copies the selected curve into the buffer.

10) Now click on the Happy.L ShapeKey Channel.
- Add a New Driver.
- Paste the curve from the buffer.


Notice that we selected "Happy.L" for the Bone Driver.


Now Judge the Results!

Here is the Blend File of what we have done so far: ant03b.blend