The geometric channel of the animal B-ultrasound is first at the entrance of the pipeline and has not undergone any transformation, so all vertices of a model are explained relative to a local coordinate system. The orientation of this coordinate system is generally referred to as the model space, and each coordinate system is also referred to as the model coordinate system.

The first stage of the geometric pipeline in animal ultrasound is to transform the vertices of a model from their local coordinate system to a coordinate system shared by objects in the scene. This process is called world transformation. This new orientation is commonly referred to as world space, and every vertex in world space is represented using world coordinates.

Next, the vertices are redirected according to the camera. That is to say, the program selects an observation point and relocates and rotates the world coordinate system around the camera, thereby transforming the world space into the camera space, which is called visual transformation.

The geometric pipeline of animal ultrasound is followed by perspective transformation. In this part of the pipeline, objects are usually scaled according to their position relative to the observation point to give them a sense of distance; Make nearby objects appear larger than those in the distance. For simplicity, this article refers to the space where the vertices that have undergone perspective transformation are located as the perspective space.

The last part of the geometric pipeline in animal ultrasound is to crop the vertices, removing the vertices that cannot be seen on the screen. This can save raster processing time and allow it more time to process the colors and brightness of visible parts. This process is called pruning. After cropping, the remaining vertices are scaled according to viewport parameters and converted to the screen coordinate system. The final vertices obtained through raster processing will exist in screen space.