Blendshapebased

Blendshapebased refers to a technique used in computer graphics and animation to deform a 3D model's mesh. It involves creating a series of pre-defined target shapes, also known as blendshapes or morph targets, which represent different expressions, poses, or modifications of the base model. By blending these target shapes together with varying degrees of influence, animators can create smooth and natural transitions between different states of the model.

The process typically begins with a base mesh, which is the neutral or default state of the model. Then, several target meshes are created, each representing a specific deformation. For example, in character animation, target shapes might include a smile, a frown, a surprised expression, or a blinking eye. These target meshes must have the same number of vertices and the same vertex order as the base mesh to ensure proper interpolation.

During animation, each blendshape is assigned a weight, which determines how much of that target shape is applied to the base mesh. These weights can be animated over time, allowing for dynamic changes in the model's appearance. For instance, a character's mouth shape can be manipulated by blending different phoneme-specific blendshapes to create speech. This method is widely used in video games, film, and virtual reality for character facial animation and other forms of mesh deformation.