3D Dirichlet free-form deformation (three-dimensional Dirichlet free deformation)

The free-form deformation (FfD) method is a common deformation method unrelated to object representation. It is widely used in computer animation and geometric modeling. The FFD method does not directly deform the object, but deformation the space embedded in the object. While Dirichlet free deformation (dffd)AlgorithmFfD is a widely used FFD improvement algorithm. The dffd algorithm is more flexible and can set any control point without defining a control box. The dffd algorithm is mainly based on the Dirichlet and KNN graphs.

 

In this article, we use the dffd algorithm to perform free deformation on the human head. For the sake of simplicity, we have selected eight vertices of the box slightly larger than the box surrounded by the human head as the control points, as shown in:

The following shows the corresponding free deformation effect of the head model when moving a certain control point. Is the initial head without the dffd Deformation:

 

 

1. Move the control point 0 to the right, up, and down, respectively, five units. The deformed head is shown in:

 

2. Move the control point 0 to the left, down, and outward, as shown in the following figure:

 

3. Move Control Point 1 to the right, up, and up, respectively, and move 5 units to the inside. The deformed head is shown in:

 

4. Move Control Point 1 to the left, down, and outward, as shown in the following figure:

 

5. Move Control Point 1 to the right of 10 units, as shown in the following figure:

 

6. Move the control point 4 to the left of 10 units, as shown in the following figure: