williams-et-al-1983-apple-ii-computer-graphics

182 APPLE II COMPUTER GRAPHICSCOLOR GROUP. Bytes displayed on the Hi-Res screen belong to one oftwo color groups. Bytes in group 1 may display dots which are black,white, green, or violet; bytes in group 2 may display black, white, blue,or orange.COLUMN ADDRESS. The - portion of the address of a byte on the graphicsscreen which must be determined by that byte's position across thescreen.CONTACT METHOD. A method for detecting collisions only when oneshape actually contacts another, as opposed to the Box Method .COORDINATES, X and Y. The X-coordinate indicates a horizontal position,and the Y-coordinate indicates a vertical position.DECIMAL. The normal system of numeration which uses ten digits, (/)through 9.DIGITIZE. To create a series of data values for a figure or other nonnumericitem.DITHERING. A technique which places several of the the six elementaryApple Hi-Res colors in a pattern so it produces non-standard colors.DOS. An acronym for disk operating system, the controlling programsthat make your disks behave properly (usually).DRAW. An APPLESOFT command which draws a shape on the Hi-Resscreen.EDITOR. A program to simplify creating, altering, and saving either textor graphics.EXCLUSIVE OR (EOR). A Boolea n (binary) operation which comparestwo bits and results in an ON state if either of the compared bits are ONbut not if both are ON.EXEC. A DOS command which causes the computer to process the contentsof a text fi le in the same way it usually handles keyboard input.FLICKER. Flash on and off quickly. Flicker is the bane of animation programmers.FULL-SCREEN GRAPHICS.text at the bottom.The graphics screens without four lines ofHEX or HEXADECIMAL. Referring to hexadecimal; a system of numerationusing 16 diffe rent characters for digits: (/)through 9 and A through F.Hex numbers are conventionally preceded by a "$" to diffe rentiatethem from other types of numbers. $A is decimal 1 f/J, $B is decimal 11,and so forth.HIMEM. The value which represents the top of user-available memory.The APPLESOFT variables use HIMEM as a starting point.