What Does Volume Pixel Mean?
A volumetric pixel (volume pixel or voxel) is the three-dimensional (3D) equivalent of a pixel and the tiniest distinguishable element of a 3D object. It is a volume element that represents a specific grid value in 3D space. However, like pixels, voxels do not contain information about their position in 3D space. Rather, coordinates are inferred based on their designated positions relative to other surrounding voxels. One may compare volume pixels to bricks, which are stacked and used to build bigger structures. In this scenario, each brick is placed next to each other, but the bricks are not defined.
Techopedia Explains Volume Pixel
Volume pixels are used like building blocks to form a larger 3D object. Like stacked bricks, voxels do not contain specific information about their axis coordinates. Rather, they have some information about their relative location in relation to nearby voxels and are considered single points in 3D space. They are good for representing regular sample shapes that are not homogeneously filled, in contrast to polygons and points, which are explicitly presented by the coordinates of their points (vertices). Polygons more efficiently represent simple 3D shapes by creating the surfaces and using a great deal of homogeneously filled space.
Voxels have the ability to contain multiple scalar values (vector data), such as density, opacity, color and volumetric flow rate. Thus, they are used extensively for visualization and analysis of scientific and medical data from devices like CT scanners and x-ray/ultrasound machines. Some game engines also use voxels and volumetric data to create terrain and vegetation.