Alpha mapping is a process in 3D CGI that adds transparency to an object. It involves creating a grayscale texture map that indicates different levels of opacity, with white being solid and black being transparent. This process is used to add extra realism and detail to objects without changing the polygon count.
Alpha mapping is a process by which a texture is applied to an object in 3D (XNUMXD) Computer-Generated Imagery (CGI) which creates transparency. The term “opacity” is often used in computer graphics and full opacity means that an object is solid, while no opacity means a transparent object. Alpha mapping is the creation of a texture map for an object that provides no color or texture, but instead indicates various levels of opacity for it. The map for this is typically created as a grayscale object: where white indicates full opacity, black is transparent, and different shades of gray represent gradients between these two extremes.
While alpha mapping may seem complex, the process and methodology behind it is actually quite simple. 3D CGI objects are created as a series of shapes or polygons that are linked together to create a larger shape. A square box, for example, can be made using just six polygons, with a single four-sided shape on each side to create a box. More complex objects are made in much the same way, although they can be made up of many more polygons needed to create curves and other details.
Over this shape, often called a “mesh”, a number of different “maps” are applied to add colour, images and textures. That plain box can have a texture map applied to it that looks like wooden planks, so that each side looks like it was assembled from wood. This is often a fairly complicated process involving a number of different maps that are combined to make the mesh as realistic as possible.
Alpha mapping is simply a part of this larger process that adds extra realism and can be used to add detail in a number of ways. Different types of images can be used when alpha mapping, although the image used is usually a simple grayscale graph. This means that it contains no color, but instead consists only of black, white, and shades of gray. The image created in this way is called an “alpha map”.
Once the map is applied to an object, the white parts in the alpha map appear normal, while the black parts become completely transparent. Different shades of gray can be used in alpha mapping to indicate varying degrees of opacity. Tones closer to white are more solid, while those closer to black are more transparent. This doesn’t actually change the mesh itself, just its appearance.
Alpha mapping is important for creating realistic computer graphics that aren’t overly demanding to render or display. If an artist wanted to create a hole in the box in the example above, doing so would require a change in the polygon count to create the shape of the hole in one of the sides. Using alpha mapping, however, allows an artist to simply create a map with a black area for the hole, which becomes transparent in the final image.
Protect your devices with Threat Protection by NordVPN
