2D computer graphics

2D computer graphics. 2D computer graphics are the computer-based generation of digital images—primarily from two-dimensional models, such as vector graphics and raster graphics, and by techniques specific to them. This field forms the foundational layer for much of digital visual media, distinct from the three-dimensional geometry and lighting simulations of 3D computer graphics. Its applications are ubiquitous, spanning graphical user interface design, typography, cartography, computer-aided design, and the vast majority of video game genres, from classic arcade games to modern indie game developments.

Overview

The domain of 2D computer graphics is primarily concerned with the synthesis and manipulation of images on a planar, two-dimensional space, such as a computer monitor or printer output. Core operations include the creation of geometric primitives like lines and curves, the filling of shapes with color or patterns, the compositing of multiple image layers, and the application of spatial transformations such as rotation, scaling, and translation. Early systems were pioneered at institutions like the Massachusetts Institute of Technology with projects such as Sketchpad, developed by Ivan Sutherland. The field is fundamentally divided between the object-oriented approach of vector graphics, used in formats like SVG and by software such as Adobe Illustrator, and the pixel-based approach of raster graphics, which underpins digital photography and is managed by programs like Adobe Photoshop.

Fundamental concepts

The mathematical foundation for 2D graphics is primarily coordinate geometry, where points are defined on a Cartesian coordinate system. Key primitives include points, line segments, polygons, and Bézier curves, which are defined by control points. The representation of color is critical, utilizing models such as RGB color model for display and CMYK color model for print. The process of rasterisation converts vector descriptions into a pixel grid for display. Essential algorithms in this domain include those for line drawing, like Bresenham's line algorithm, and for polygon filling, such as the scanline rendering algorithm. The alpha channel, introduced with systems like the Pixar RenderMan interface, enables advanced image compositing and transparency effects.

Rendering techniques

Rendering in 2D involves generating a final pixel image from higher-level descriptions. For vector graphics, this entails tessellating shapes into triangles or other simple polygons for filling. Sprite-based rendering, popularized by arcade systems from companies like Nintendo and Sega, involves blitting pre-drawn bitmap images onto a framebuffer. Tile-based rendering, used in early role-playing video games and platforms like the Nintendo Entertainment System, constructs scenes from a grid of reusable graphic blocks. More advanced techniques include image scaling algorithms like bilinear interpolation and bicubic interpolation, and the use of clipping regions to define visible areas. The PostScript page description language, developed by Adobe Inc., revolutionized 2D rendering for the printing industry.

Applications

2D computer graphics are integral to modern computing and media. They are the bedrock of desktop publishing, enabled by software like Adobe InDesign and QuarkXPress, and are essential for web design and the creation of CSS-based layouts. In entertainment, they define entire genres of video games, including platform games, fighting games, and visual novels. The motion picture industry uses 2D graphics for storyboard creation, title sequence design, and traditional cel animation, with studios like Walt Disney Animation Studios and Studio Ghibli producing iconic works. Technical fields rely on them for scientific visualization, computer-aided design in engineering, and the production of maps in geographic information system software.

History and development

The history of 2D computer graphics is intertwined with the evolution of computing itself. Early experiments were conducted on machines like the Whirlwind computer at MIT and the TX-2, leading to Ivan Sutherland's groundbreaking Sketchpad system in 1963. The 1970s saw the development of the first bitmap displays and graphical user interfaces at Xerox PARC, which directly inspired the Apple Macintosh. The 1980s brought widespread adoption with the rise of personal computers from IBM and Apple Inc., alongside dedicated graphics software like MacPaint and CorelDRAW. The standardization of formats such as GIF, JPEG, and PNG facilitated the explosion of graphics on the early World Wide Web. Continued advancement is seen in high-resolution displays, sophisticated vector graphics standards like SVG, and their persistent use in mobile game development and user interface design across all platforms. Category:Computer graphics Category:Digital art