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The representation and manipulation of image data by a computer is called computer graphics. It is shortly called CG. The development in this field has created a drastic change in media such as animation and the video game industry. Most of the amazing effects in theaters are a result of the advancement in computer graphics. Here we are going to discuss some of the basic concepts and principles in CG.
Image:
An image image is nothing more than a work of art that resembles a person or a physical object. This representation of a physical object or a person can be two-dimensional or three-dimensional. Optical devices like lenses, mirrors, cameras are used to capture such images. A digital image is a representation of a two-dimensional image in binary format, that is, as a sequence of 1s and 0s. Raster and vector images are the two types of digital images. But raster images are the most used.
pixels:
The resolution of an image is often based on the number of pixels in the image. When the image is viewed in an enlarged portion, you may notice the individual pixels as squares. In general, pixels are arranged on an ordinary two-dimensional grid, and dots or squares are often used to represent them. Each and every pixel differs in color systems and intensity. A single pixel can be considered as a sample of an image. Increasing the number of pixels, that is, increasing the samples, results in the exact representation of the original image.
Graphics:
The combination of text, illustration, and color is called Graphics. They are the visual representation of any object on the surface, such as the computer screen, the wall, the paper, etc. Photographs, drawings, maps, diagrams are some of the examples. The main objective of the Graphics is to create a style that is unique or effective communication associated with cultural elements.
Representation:
Using computer programs, an image can be generated from a model. This process is called rendering. The model contains point of view, geometry, texture, lighting, etc. The image may be a raster graphics image or a digital image. To produce the final video output, this process is used to calculate the effects in a video editing file.
3D projection:
This type of projection is widely and most preferably used in CG, drafting, and engineering. It is a method of mapping 3-dimensional points to a 2-dimensional plane. Currently, only a two-dimensional plane is used to display graphical data.
Ray tracing:
Using this technique, an image can be generated by tracing the path of the light ray through the pixel in an image plane. It has the ability to produce images with extreme photorealism at a higher computational cost.
Shading:
It refers to rendering artwork or depth in 3D models at different levels of darkness. There are various shading techniques in which perpendicular lines are drawn in a criss-cross pattern to shade an area.
Texture mapping:
This method is used to add surface texture, color, or any detail to a 3D model or computer generated graphic. A texture map can be assigned to the surface of a shape, for example a polygon.