Title
Definition and use of higher-level graphics input tools
Abstract
A proposal is made for the definition of 'tools', high-level graphics input functions based on the six primitive input classes Clock, Pick, Button, Key, Valuator and Locator. Tools are defined in terms of input expressions, the operands of which are themselves tools, the definition of which may be nested inside this tool. Input expressions are written much like production rules in phrase structure grammars. Determining whether a tool is 'satisfied' can therefore be done most advantageously by an input expression parser. Tool definitions may occur in-line or stored in a library. They are activated by a 'create' primitive, which creates an instance of the tool and causes the input expression to be made active. The parser then determines whether a tool is actually used. Following a 'read' issued to the tool, the tool body generates the returned information as specified by the tool definition. Tools may be explicitly freed by a 'free' primitive; in the case of nesting, tools are freed implicitly when the surrounding tool is freed. Using this approach to higher-level input primitives, a programmer does not have to think about graphics input in terms of awaiting events, interrupts and the like. The creation of a defined tool implies a function awaiting action from the tool.
Year
DOI
Venue
1978
10.1145/800248.807367
SIGGRAPH
Keywords
Field
DocType
Computer graphics,Graphics input,Graphics tools,High-level input tools,Input devices,Interaction
Graphics,Rule-based machine translation,Programmer,Programming language,Computer graphics (images),Expression (mathematics),Computer science,Operand,Theoretical computer science,Parsing,Computer graphics,Input device
Conference
Volume
Issue
ISSN
12
3
0097-8930
Citations 
PageRank 
References 
15
27.48
4
Authors
2
Name
Order
Citations
PageRank
Jan Van Den Bos19167.60
BosJan Van den21527.48