利用者:Apinzonf/shape enhanced

Shape Enhanced

Shape enhanced method exaggerates a shape using a Laplacian smoothing operator in the reverse direction.

Methodology

A diffusion process is used:

<math> \delta V / \delta t = \lambda L(V) </math>

Integrating the diffusion equation with a explicit Euler scheme:

<math> (I - |\lambda dt| W_p L) V' = V^t</math>

<math> V^{t+1} = V^{t} + \text{sing} (\lambda ) (V^' - V^t)</math>

The vertices <math> V^{t+1} </math> are enhanced in the reverse direction of curvature flow.

Where L is the Laplace Beltrami Operator, V' are the smoothing vertices, <math> V^t </math> are the actual vertices positions, <math> W_p </math> is a diagonal matrix with weight vertex group, and <math> \lambda dt </math> is the enhancement factor that supports negative and positive values: negative for enhancement and positive for smoothing.

Implementation

modifiers/intern/MOD_laplaciansmooth.c

Implementation of this method only require small changes in Laplacian smooth method, the changes are presented in this patch.

Is necessary adding a checkbox in Laplacian Smooth Modifier interface, to customize the kind of Laplace operator, (Traditional or Normalized).

Results

Top row: From left to rigth. Shape enhanced with <math> \lambda=-400.0 </math> , <math> \lambda=-100.0 </math>, Original model, <math> \lambda=50.0 </math>. Bottom row: Shape enhancement with weight vertex group, <math> \lambda=-50.0 </math> for the legs, <math> \lambda=-200.0 </math> for the head and neck.