SuperPaint

Super Paint was an early paint program and part of a larger graphics system, which also included specially designed hardware. It was designed from 1972 to 1975 by Richard Shoup at Xerox PARC and developed with the participation of Alvy Ray Smith, Bob Flegal and Patrick Baudelaire. The first image generated with Super Paint was the beginning of April 1973.

User interface

Super Paint was running on a Data General Nova 800 computer that used a then new graphics tablet for drawing and had several floppy drives for loading and saving images. Great emphasis was placed on ease of use. The user interface consisted of three screens with a resolution of each 640 × 480 pixels and a color depth of 4 bits, whereby 16 different colors were possible. A screen showed the work area, another the menu of editing tools, as well as the currently selected color; the third was used to enter file names on a command line and to issue brief instructions for operation, depending on the currently selected tool.

The colors were selected using the HSB color space. Super Paint allowed to draw, among other lines, and delete to create custom brushes and fill areas. Other features were the enlargement and reduction of images, copying or moving parts of an image, inserting text or replacing colors. It was also possible to load an image via a video interface. By Color cycling, the rotation of a maximum of ten color palette entries, even simple animations were possible. Later, Shoup also wrote routines for anti-aliasing.

Technology

The Super Paint system used one of the first frame buffer for storing the currently displayed image. This memory, which allowed a resolution of 640 × 480 pixels at 8 -bit color depth, consisted of 16 circuit boards with a total capacity of 307,200 bytes, and was in two identical memory banks grouped. The entire memory was rotated with the aid of MOS shift registers in synchronism with the display of the image on the screen. The color of a given pixel could only be changed if it has just been rotated to the correct position. To represent the color- indexed image were used Color Look - Up Tables of 256 × 8 × 3 static RAM chips. Two multiplexers controlled the flow of data pixel by pixel. The first selected the input data of the frame buffer between the computer video input or the framebuffer ( for rotation ). The second controlled the entrance to the color tables and thus the output of the digital-to- analog converter and the display output.

The image was superimposed by moving, arbitrarily shaped cursor or brush that has not been stored in the frame buffer, but supplied by the relatively slow main processor. Thus, the image data could not be delivered in real time, they were RLE and uncompressed in memory. The opaque pixels in the cursor is changed from the first to the second multiplexer, for outputting the image data of the cursor.

The programming language BCPL and assembly language was used. The system is changed in the course of time several times and expanded to allow additional features.

Use and influence

Although Super Paint was intended primarily for research purposes, it was used until the late 1970's, for some projects. One of the first computer graphics for television programs were created in the late 1970s by Damon Rarey for the PBS show Over Easy with Help from Super Paint, including eye-catching many animations. The cost of producing these graphics were significantly lower than in conventional design methods. From the end of 1978 produced Damon Rarey with Super Paint dozens of graphics for visualizing spacecraft maneuvers as part of the Pioneer Venus mission.

For his pioneering work in the development of digital paint programs Shoup in 1983 was awarded an Emmy and 1998, together with Alvy Ray Smith and Thomas Porter won an Oscar for science and development.

The Super Paint system is still functional and is now in the Computer History Museum, California.