xerox 19771024 Simple Display Package free download

File name 19771024_Simple_Display_Package.pdf

Inter-Office Memorandum To Mesa Users Date October 24, 1977 From R. 10hnsson Location Palo Alto Subject Simple Display Package Organization SDD/SD XEROX SDD ARCHIVES XEROX I have read and understood Pages _________To _________ Reviewer _________ Date _______ Filed on: [MAXC1 ]SimpleDisplay.bravo :# of Pages ____ Ref .. 11~1,)1> This memo describes a simplified display package which may be of interest to some Mesa users. The package uses the DeB-per-line mode of operation in order to increase scroll speed and maximize the amount of text that can be displayed for a given amount of memory. There is no provision for other than Teletype style useage, i.e., there is no support for pointing. selecting. etc. This package can be used to replace the Display. Menus, Rectangles. and Windows modules in the standard Mesa system for applications which do not require the generality of those interfaces. The modules described here may be used separately or may be used in the configuration SimpJeDisplay which includes a standard control module. Fonts FontDefs defines the interface to Font objects. FontDefs: DEFINITIONS = BEGIN BitmapState: TYPE = RECORD [ origin: POINTER. wordsPerLine, x, y: CARDINAL]; FontObject: TYPE = RECORD [ paintChar: PROCEDURE [FontHandle, CHARACTER, POINTER TO BitmapState], clearChar: PROCEDURE [FontHandle, CHARACTER, POINTER TO BitmapState], charWidth: PROCEDURE [FontHandle, CHARACTER] RETURNS [CARDINAL], charHeight: PROCEDURE [FontHandle, CHARACTER] RETURNS [CARDINAL], close: PROCEDURE [FontHandle], destroy: PROCEDURE [FontHandle], lock: PROCEDURE [FontHandle] RETURNS [POINTER], unlock: PROCEDURE [FontHandle]]; FontHandle: TYPE = POINTER TO FontObject; CharWidth: PROCEDURE [font: FontHandle, char: CHARACTER] RETURNS [CARDINAl.]; CharHeight: PROCEDURE [font: FontHandle, char: CHARACTER] RETURNS [CARDINAL]; CreateFont: PROCEDURE [SegmentDefs.FileSegmentHandle] RETURNS [FontHandle]; Simple Display Package 2 END. A FontObject contains the following operations: paintChar: copies the specified cha