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

GLOSSARY 183HI-RES. High Resolution graphics. In Hi-Res graphics, all objects displayedare made up of a number of small dots on the screen.HI-RES PAG ES. The area in memory which may be displayed as pictureson the video output.HI-RES ROUTINE. A program designed to manipu late the contents ofthe Hi-Res pages of the Apple memory.HI-ORDER BYTE. In an address, the most significant (left-most) byte. Forexample, in the hex address $A3©F, A3 is the hi-order byte (hi-byte).HUN.A BASIC command used to draw a horizontal line in Low-Res.LO-BYTE/HI-BYTE. The form Apple uses for hex addresses; the loworderbyte comes before the hi-order byte.LOW-RES. A graphics mode of the Apple II where the video output is anumber of small colored blocks.LOW-ORDER BYTE. In an address, the least significant (right-most) byte.For example, in the hex address $A3©F, ©F is the low-order byte (lobyte).MEMORY.MEMORY MAP.Data storage area within the computer.MIXED SCREEN GRAPHICS.at the bottom.A diagram of the computer' s memory.The graphics screen with four lines of textMONITOR. The ROM resident machine-level language in your Apple. Ifwritten without the capital "M," the video display.MOVE.NIBBLE/NYBBLE.byte.A command available from Monitor to move a block of memory.Either of the first or last four bits in a byte-half of aOFFSET. A value added to the base address to locate a byte with respectto that base address.OPTIMIST.A programmer who codes in pen.PAGE. A unit of memory. 256 bytes of memory make up one page.When used in the context of graphics display, a page refers not to 256bytes, but to the area of memory which is to be displayed on the videoscreen.PARTIAL MODIFICATION. An animation technique where only the portionsof the figure which change are redrawn. The rest are left alone.PEEK. A BASIC command which looks at a specified address in memoryand returns the value that it finds there.PIXEL.The smallest unit of video display controllable by the computer.