DIRECTORY
DeviceClassTypes, DeviceTypes, FastTRAPDevice, Rope;

FastTRAPDeviceImpl: CEDAR PROGRAM
IMPORTS
EXPORTS FastTRAPDevice, DeviceTypes = BEGIN

Device: TYPE = DeviceTypes.Device;
DeviceObj: TYPE = DeviceTypes.DeviceObj;
DeviceClass: PUBLIC TYPE = DeviceClassTypes.DeviceClass;
DeviceClassObj: PUBLIC TYPE = DeviceClassTypes.DeviceClassObj;
DeviceState: TYPE = DeviceTypes.DeviceState;
DeviceStateObj: TYPE = DeviceTypes.DeviceStateObj;
DeviceStateChange: TYPE = DeviceTypes.DeviceStateChange;
DeviceStateChangeObj: TYPE = DeviceTypes.DeviceStateChangeObj;
KeyName: TYPE = FastTRAPDevice.KeyName;
ROPE: TYPE = Rope.ROPE;

FastTRAPData: TYPE = REF FastTRAPDataObj;
FastTRAPDataObj: TYPE = RECORD [
name: ROPE
];

FastTRAPState: TYPE = REF FastTRAPStateObj;
FastTRAPStateObj: TYPE = RECORD [
wheel: INTEGER,
x, y: INTEGER, -- trackball coordinates
buttonDown: ARRAY KeyName OF BOOL
];

fastTRAPClass: DeviceClass м NEW[DeviceClassObj м [$FastTRAP, GetFastTRAPState]];

GetFastTRAPState: DeviceClassTypes.GetDeviceStateProc = {
state м AllocateState[device];
};

CreateFastTRAP: PUBLIC PROC [name: Rope.ROPE] RETURNS [device: Device] = {
data: FastTRAPData м NEW[FastTRAPDataObj м [name: name]];
device м NEW[DeviceObj];
device.class м fastTRAPClass;
device.data м data;
device.name м name;
};

AllocateState: PUBLIC PROC [device: Device] RETURNS [deviceState: DeviceState] = {
state: FastTRAPState м NEW[FastTRAPStateObj м [wheel: 0, x: 0, y: 0, buttonDown: [FALSE, FALSE, FALSE]]];
deviceState м NEW[DeviceStateObj];
deviceState.class м device.class;
deviceState.state м state;
};
CopyState: PROC [deviceState: DeviceState] RETURNS [copy: DeviceState] = {
old: FastTRAPState м NARROW[deviceState.state];
state: FastTRAPState м NEW[FastTRAPStateObj м [wheel: old.wheel, x: old.x, y: old.y, buttonDown: old.buttonDown]];
copy м NEW[DeviceStateObj];
copy.class м deviceState.class;
copy.state м state;
};


buttonDownChange: ARRAY KeyName OF ARRAY BOOL OF DeviceStateChange;
trackballChange: ARRAY [-4..4] OF ARRAY [-4..4] OF DeviceStateChange;
wheelChange: ARRAY [-4..4] OF DeviceStateChange;

Init: PROC = {
buttonDownChange[left][FALSE] м KeyChangeCreate[left, FALSE];
buttonDownChange[left][TRUE] м KeyChangeCreate[left, TRUE];
buttonDownChange[middle][FALSE] м KeyChangeCreate[middle, FALSE];
buttonDownChange[middle][TRUE] м KeyChangeCreate[middle, TRUE];
buttonDownChange[right][FALSE] м KeyChangeCreate[right, FALSE];
buttonDownChange[right][TRUE] м KeyChangeCreate[right, TRUE];
FOR i: INT IN [-4..4] DO
FOR j: INT IN [-4..4] DO
trackballChange[i][j] м TrackballChangeCreate[i, j];
ENDLOOP;
wheelChange[i] м WheelChangeCreate[i];
ENDLOOP;
};

KeyChange: PUBLIC PROC [key: KeyName, down: BOOL] RETURNS [change: DeviceStateChange] = {
change м buttonDownChange[key][down];
};

TrackballChange: PUBLIC PROC [deltaX, deltaY: INTEGER] RETURNS [change: DeviceStateChange] = {
IF deltaX IN [-4..4] AND deltaY IN [-4..4] THEN change м trackballChange[deltaX][deltaY]
ELSE {
change м TrackballChangeCreate[deltaX, deltaY];
};
};

ThumbwheelChange: PUBLIC PROC [delta: INTEGER] RETURNS [change: DeviceStateChange] = {
IF delta IN [-4..4] THEN change м wheelChange[delta]
ELSE {
change м WheelChangeCreate[delta];
};
};

KeyChangeCreate: PROC [key: KeyName, down: BOOL] RETURNS [dsChange: DeviceStateChange] ~ {
change: FastTRAPChange м NEW[FastTRAPChangeObj];
change.type м key;
change.key м key;
change.down м down;
dsChange м NEW[DeviceStateChangeObj];
dsChange.class м fastTRAPClass;
dsChange.change м change;
};

TrackballChangeCreate: PROC [deltaX, deltaY: INTEGER] RETURNS [dsChange: DeviceStateChange] ~ {
change: FastTRAPChange м NEW[FastTRAPChangeObj];
change.type м trackball;
change.deltaX м deltaX;
change.deltaY м deltaY;
dsChange м NEW[DeviceStateChangeObj];
dsChange.class м fastTRAPClass;
dsChange.change м change;
};

WheelChangeCreate: PROC [delta: INTEGER] RETURNS [dsChange: DeviceStateChange] ~ {
change: FastTRAPChange м NEW[FastTRAPChangeObj];
change.type м wheel;
change.deltaX м delta;
dsChange м NEW[DeviceStateChangeObj];
dsChange.class м fastTRAPClass;
dsChange.change м change;
};

FastTRAPChange: TYPE = REF FastTRAPChangeObj;
FastTRAPChangeObj: TYPE = RECORD [
type: ChangeType,
key: KeyName м left,
down: BOOL,
deltaX, deltaY: INTEGER м 0
];
ChangeType: TYPE = {key, trackball, wheel};

StateAfterChange: PUBLIC PROC [deviceState: DeviceState, change: DeviceStateChange] RETURNS [newDeviceState: DeviceState] = {
ftChange: FastTRAPChange м NARROW[change.change];
SELECT ftChange.type FROM
key => newDeviceState м KeyMotion[deviceState, ftChange.key, ftChange.down];
trackball => newDeviceState м TrackballMotion[deviceState, ftChange.deltaX, ftChange.deltaY];
wheel => newDeviceState м ThumbwheelMotion[deviceState, ftChange.deltaX];
ENDCASE => ERROR;
};

ExpandedChange: TYPE = FastTRAPDevice.ExpandedChange;
UnpackChange: PUBLIC PROC [change: DeviceStateChange] RETURNS [expanded: ExpandedChange] = {
ftChange: FastTRAPChange м NARROW[change.change];
SELECT ftChange.type FROM
key => expanded м [key[ftChange.key, ftChange.down]];
trackball => expanded м [trackball[ftChange.deltaX, ftChange.deltaY]];
wheel => expanded м [wheel[ftChange.deltaX]];
ENDCASE => ERROR;
};


KeyMotion: PUBLIC PROC [deviceState: DeviceState, key: KeyName, down: BOOL] RETURNS [newDeviceState: DeviceState] = {
newDeviceState м CopyState[deviceState];
NARROW[newDeviceState.state, FastTRAPState].buttonDown[key] м down;
};

TrackballMotion: PUBLIC PROC [deviceState: DeviceState, deltaX, deltaY: INTEGER] RETURNS [newDeviceState: DeviceState] = {
newState, oldState: FastTRAPState;
newDeviceState м CopyState[deviceState];
newState м NARROW[newDeviceState.state];
oldState м NARROW[deviceState.state];
newState.x м oldState.x + deltaX;
newState.y м oldState.y + deltaY;
};

ThumbwheelMotion: PUBLIC PROC [deviceState: DeviceState, delta: INTEGER] RETURNS [newDeviceState: DeviceState] = {
newDeviceState м CopyState[deviceState];
NARROW[newDeviceState.state, FastTRAPState].wheel м NARROW[deviceState.state, FastTRAPState].wheel + delta;
};

IsDown: PUBLIC PROC [deviceState: DeviceState, key: KeyName] RETURNS [BOOL] = {
state: FastTRAPState м NARROW[deviceState.state];
RETURN[state.buttonDown[key]];
};
GetTrackball: PUBLIC PROC [deviceState: DeviceState] RETURNS [x, y: INTEGER] = {
state: FastTRAPState м NARROW[deviceState.state];
x м state.x;
y м state.y;
};
GetThumbwheel: PUBLIC PROC [deviceState: DeviceState] RETURNS [wheel: INTEGER] = {
state: FastTRAPState м NARROW[deviceState.state];
wheel м state.wheel;
};

Init[];

END.

  ╠  
FastTRAPDeviceImpl.mesa
Copyright ╙ 1991, 1992 by Xerox Corporation.  All rights reserved.
Bier, November 6, 1991 10:43 am PST
Contents:  Routines for creating instances of the FastTRAP trackball and representing the state of such a device.

Class Routines
PROC [device: Device] RETURNS [state: DeviceState];
Create a data structure representing a particular physical FastTRAP.  Calls class.create[class].
Allocates storage representing the state of this keyboard when all of its keys are up, the trackball is at 0,0, and the thumbwheel is at 0.  Each DeviceState is immutable, so they may be freely stored in long-term storage.

Representing FastTRAP State Changes
Changing FastTRAP State
Inspecting State

 Э╩G  Ц(cedarcode) styleХNewlineDelimiter
Щ codeЪЬЩKЪЬ	╧eЬ6ЩBKЪЬ#Щ#KЪЬqЩqKЩ ЧЪ╧k	Ш	KЪЬ4Ш4ЧKШ ЪЬЮЬЮШ!KЪЮШKЪЮЬЮШ+ЧKШ KЪЬЮЬШ"KЪЬЮЬШ(KЪЬЮЬЮЬ Ш8KЪЬЮЬЮЬ#Ш>KЪЬЮЬШ,KЪЬЮЬШ2KЪЬЮЬ!Ш8KЪЬЮЬ$Ш>KЪЬ	ЮЬШ'KЪЮЬЮЬЮЬШKШ KЪЬЮЬЮЬШ)ЪЬЮЬЮЬШ KЪЬЮШ
KШKШ ЧKЪЬЮЬЮЬШ+ЪЬЮЬЮЬШ!KЪЬЮЬШKЪЬЮЬ╧cШ'KЪЬЮЬ	ЮЬЮШ!KШKШ ЧЪЬЮЬ1ШQKШ ЧKЩЪ╧nЬ)Ш9KЪЮЬЮЬЩ3KШKШKШ ЧЪ
аЬЮЬЮЬЮЬЮЬШJKЪЬ`Щ`KЪЬЮЬ!Ш9KЪЬ	ЮЬШKШKШKШKШЧKШ ЪаЬЮЬЮЬЮЬШRKЪЬ▐Щ▐KЪ	ЬЮЬ8ЮЬЮЬЮЬШiKЪЬЮЬШ"KШ!KШKШKЩ ЧЪа	ЬЮЬЮЬШJKЪЬЮЬШ/KЪЬЮЬXШrKЪЬЮЬШKШKШKШKШ ЧЪЬ#Щ#KШ ЧKЪЬЮЬ	ЮЬЮЬЮЬЮЬШCKЪ	ЬЮЬ	ЮЬЮЬ	ЮЬШEKЪЬЮЬ	ЮЬШ0KШ ЪаЬЮЬШKЪЬЮЬЮЬШ=KЪЬЮЬЮЬШ;KЪЬЮЬЮЬШAKЪЬЮЬЮЬШ?KЪЬЮЬЮЬШ?KЪЬЮЬЮЬШ=ЪЮЬЮЬЮЬ	ЮШЪЮЬЮЬЮЬ	ЮШKШ4KЪЮЬШЧKШ&KЪЮЬШЧKШЧKШ Ъ
а	ЬЮЬЮЬЮЬЮЬ ШYKШ%KШKШ ЧЪ
аЬЮЬЮЬЮЬЮЬ Ш^KЪ
ЮЬЮЬ	ЮЬЮЬ	ЮЬ)ШXЪЮЬШKШ/KШЧKШKШ ЧЪ
аЬЮЬЮЬ	ЮЬЮЬ ШVKЪЮЬЮЬ	ЮЬШ4ЪЮЬШKШ"KШЧKШKШ ЧЪаЬЮЬЮЬЮЬ"ШZKЪЬЮЬШ0KШKШKШKЪЬЮЬШ%KШKШKШKШ ЧЪаЬЮЬЮЬЮЬ"Ш_KЪЬЮЬШ0KШKШKШKЪЬЮЬШ%KШKШKШKШ ЧЪаЬЮЬ	ЮЬЮЬ"ШRKЪЬЮЬШ0KШKШKЪЬЮЬШ%KШKШKШKШ ЧKЪЬЮЬЮЬШ-ЪЬЮЬЮЬШ"KШKШKЪЬЮЬШKЪЬЮЬШKШЧЪЬЮЬШ+KШ ЧЪаЬЮЬЮЬ7ЮЬ"Ш}KЪЬЮЬШ1ЪЮЬЮШKШLKШ]KШIKЪЮЬЮЬШЧKШЧKШ KЪЬЮЬ!Ш5ЪаЬЮЬЮЬЮЬШ\KЪЬЮЬШ1ЪЮЬЮШKШ5KШFKШ-KЪЮЬЮЬШЧKШKШ ЧKЪЬЩKШ Ъ
а	ЬЮЬЮЬ0ЮЬЮЬ"ШuKШ(KЪЮЬ=ШCKШЧKШ Ъ
аЬЮЬЮЬ,ЮЬЮЬ"ШzKЪЬ"Ш"KШ(KЪЬЮЬШ(KЪЬЮЬШ%KШ!KШ!KШЧKШ Ъ
аЬЮЬЮЬ#ЮЬЮЬ"ШrKШ(KЪЮЬ.ЮЬ1ШkKШЧKШ KЩKЩ Ъ
аЬЮЬЮЬ*ЮЬЮЬШOKЪЬЮЬШ1KЪЮЬШKШЧЪ
аЬЮЬЮЬЮЬЮЬШPKЪЬЮЬШ1KШKШKШЧЪ
аЬЮЬЮЬЮЬ	ЮЬШRKЪЬЮЬШ1KШKШKШ ЧKШKШ KЪЮЬШKШ Ч ЕЧ    Ш  #л  