Accessibility Computing Numerical Pointer
The Accessibility Computing Numerical Pointer is intended to be implemented as an auxiliary program which can be accessed from any program which wishes to use it.
The idea is that by using just ten digit keys and one extra key to signify ENTER that pointer events and associated information can be generated and passed to the calling program. In addition, the Accessibility Computing Numerical Pointer is intended to provide some other facilities, such as generating Unicode characters and selecting colours.
Specification
The Numerical Pointer Room
At entry the following values are set.
The response to keys is as follows.
Keying 0 moves to the Unicode room.
x value alcove
y value alcove
z value alcove
The Unicode Room
At entry the following values are set.
integer ACNP_codepoint=0
The response to keys is as follows.
Keying 0 moves to the Colour Selection room if ACNP_codepoint has the value 0. If ACNP_codepoint does not have the value 0 then the value of ACNP_codepoint is multiplied by 16.
Keying any of 1 through to 8 causes the value of ACNP_codepoint to multiplied by 16 and the value indicted by the key added to it. For example, keying 3 causes the value of ACNP_codepoint to multiplied by 16 and then have 3 added to it.
Keying 9 moves to the higher values alcove.
Keying Enter leaves the Accessibility Computing Numerical Pointer and, depending upon the implemenation, may generate a keypressed event or similar to the program from which the Accessibility Computing Numerical Pointer was accessed.
higher values alcove
Keying 0 through to 6 is used to enter the following hexadecimal items, updating the value of ACNP_codepoint and going back to the Unicode room.
key 0 for hexadecimal 9 key 1 for hexadecimal A key 2 for hexadecimal B key 3 for hexadecimal C key 4 for hexadecimal D key 5 for hexadecimal E key 6 for hexadecimal F
(Responses for 7, 8, 9 and Enter are not defined at present, they should be implemented as "do nothing".)
The Colour Selection Room
At entry the following values are set.
The response to keys is as follows.
