Unit Touch

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`TOUCH_FLAG_NONE = $00000000;`
`TOUCH_FLAG_NON_BLOCK = $00000001;`	If set device reads are non blocking (Also supported in Flags parameter of TouchDeviceRead)
`TOUCH_FLAG_PEEK_BUFFER = $00000002;`	Peek at the buffer to see if any data is available, don't remove it (Used only in Flags parameter of TouchDeviceRead)
`TOUCH_FLAG_MOUSE_DATA = $00000004;`	If set the device will write a mouse data event for each touch event
`TOUCH_FLAG_MULTI_POINT = $00000008;`	If set the device supports multi point touch
`TOUCH_FLAG_PRESSURE = $00000010;`	If set the device supports pressure value on touch points
`TOUCH_FLAG_SWAP_XY = $00000020;`	If set swap the X and Y coordinates
`TOUCH_FLAG_INVERT_X = $00000040;`	If set invert the X coordinate
`TOUCH_FLAG_INVERT_Y = $00000080;`	If set invert the Y coordinate
`TOUCH_FLAG_SWAP_MAX_XY = $00000100;`	If set swap the maximum X and Y values

Flags supported by TOUCH_CONTROL_GET/SET/CLEAR_FLAG
`TOUCH_FLAG_MASK = TOUCH_FLAG_NON_BLOCK or TOUCH_FLAG_MOUSE_DATA or TOUCH_FLAG_MULTI_POINT or TOUCH_FLAG_PRESSURE or TOUCH_FLAG_SWAP_XY or TOUCH_FLAG_INVERT_X or TOUCH_FLAG_INVERT_Y or TOUCH_FLAG_SWAP_MAX_XY;`

Touch device control code TOUCH_CONTROL_*

`TOUCH_CONTROL_GET_FLAG = 1;`	Get Flag
`TOUCH_CONTROL_SET_FLAG = 2;`	Set Flag
`TOUCH_CONTROL_CLEAR_FLAG = 3;`	Clear Flag
`TOUCH_CONTROL_FLUSH_BUFFER = 4;`	Flush Buffer
`TOUCH_CONTROL_GET_WIDTH = 5;`	Get Screen Width
`TOUCH_CONTROL_GET_HEIGHT = 6;`	Get Screen Height
`TOUCH_CONTROL_GET_MAX_X = 7;`	Get Maximum X value (Only applies to Absolute X values)
`TOUCH_CONTROL_GET_MAX_Y = 8;`	Get Maximum Y value (Only applies to Absolute Y values)
`TOUCH_CONTROL_GET_MAX_Z = 9;`	Get Maximum Z value (Only applies to Absolute Z values)
`TOUCH_CONTROL_GET_MAX_POINTS = 10;`	Get Maximum number of Touch Points
`TOUCH_CONTROL_GET_ROTATION = 11;`	Get Rotation value (0, 90, 180, 270)(Only where supported by the driver)
`TOUCH_CONTROL_SET_ROTATION = 12;`	Set Rotation value (0, 90, 180, 270)(Only where supported by the driver)

Touch buffer size TOUCH_BUFFER_*

`TOUCH_BUFFER_SIZE = 1024;`

Touch data definitions TOUCH_FINGER*, TOUCH_ID_*

Values for TTouchData.Info
`TOUCH_FINGER = $00000001;`	A finger is pressed at this touch point
Values for TTouchData.PointID
`TOUCH_ID_UNKNOWN = Word(-1);`
Values for TTouchData.PositionX
`TOUCH_X_UNKNOWN = -1;`
Values for TTouchData.PositionY
`TOUCH_Y_UNKNOWN = -1;`
Values for TTouchData.PositionZ
`TOUCH_Z_UNKNOWN = -1;`

Touch rotation TOUCH_ROTATION_*

`TOUCH_ROTATION_0 = FRAMEBUFFER_ROTATION_0;`	No rotation
`TOUCH_ROTATION_90 = FRAMEBUFFER_ROTATION_90;`	90 degree rotation
`TOUCH_ROTATION_180 = FRAMEBUFFER_ROTATION_180;`	180 degree rotation
`TOUCH_ROTATION_270 = FRAMEBUFFER_ROTATION_270;`	270 degree rotation

Touch logging TOUCH_LOG_*

`TOUCH_LOG_LEVEL_DEBUG = LOG_LEVEL_DEBUG;`	Touch debugging messages
`TOUCH_LOG_LEVEL_INFO = LOG_LEVEL_INFO;`	Touch informational messages, such as a device being attached or detached
`TOUCH_LOG_LEVEL_WARN = LOG_LEVEL_WARN;`	Touch warning messages
`TOUCH_LOG_LEVEL_ERROR = LOG_LEVEL_ERROR;`	Touch error messages
`TOUCH_LOG_LEVEL_NONE = LOG_LEVEL_NONE;`	No Touch messages

Type definitions

Touch data

PTouchData = ^TTouchData;

TTouchData = record

`Info:LongWord;`
`PointID:Word;`
`PositionX:SmallInt;`
`PositionY:SmallInt;`
`PositionZ:SmallInt;`

Touch buffer

PTouchBuffer = ^TTouchBuffer;

TTouchBuffer = record

`Wait:TSemaphoreHandle;`	Buffer ready semaphore
`Start:LongWord;`	Index of first buffer ready
`Count:LongWord;`	Number of entries ready in buffer
`Buffer:array[0..(TOUCH_BUFFER_SIZE - 1)] of TTouchData;`

Touch properties

PTouchProperties = ^TTouchProperties;

TTouchProperties = record

`Flags:LongWord;`	Device flags (eg TOUCH_FLAG_MULTI_POINT)
`Width:LongWord;`	Screen Width
`Height:LongWord;`	Screen Height
`Rotation:LongWord;`	Screen Rotation (eg TOUCH_ROTATION_180)
`MaxX:LongWord;`	Maximum (absolute) X value for the touch device
`MaxY:LongWord;`	Maximum (absolute) Y value for the touch device
`MaxZ:LongWord;`	Maximum (absolute) Z value for the touch device
`MaxPoints:LongWord;`	Maximum number of touch points

Touch enumeration callback

`TTouchEnumerate = function(Touch:PTouchDevice; Data:Pointer):LongWord;`

Touch notification callback

`TTouchNotification = function(Device:PDevice; Data:Pointer; Notification:LongWord):LongWord;`

Touch device start

`TTouchDeviceStart = function(Touch:PTouchDevice):LongWord;`

Touch device stop

`TTouchDeviceStop = function(Touch:PTouchDevice):LongWord;`

Touch device peek

`TTouchDevicePeek = function(Touch:PTouchDevice):LongWord;`

Touch device read

`TTouchDeviceRead = function(Touch:PTouchDevice; Buffer:Pointer; Size,Flags:LongWord; var Count:LongWord):LongWord;`

Touch device write

`TTouchDeviceWrite = function(Touch:PTouchDevice; Buffer:Pointer; Size,Count:LongWord):LongWord;`

Touch device flush

`TTouchDeviceFlush = function(Touch:PTouchDevice):LongWord;`

Touch device update

`TTouchDeviceUpdate = function(Touch:PTouchDevice):LongWord;`

Touch device control

`TTouchDeviceControl = function(Touch:PTouchDevice; Request:Integer; Argument1:LongWord; var Argument2:LongWord):LongWord;`

Touch device get properties

`TTouchDeviceGetProperties = function(Touch:PTouchDevice; Properties:PTouchProperties):LongWord;`

Touch device

PTouchDevice = ^TTouchDevice;

TTouchDevice = record

Device Properties
`Device:TDevice;`	The Device entry for this Touch device
Touch Properties
`TouchId:LongWord;`	Unique Id of this Touch device in the Touch device table
`TouchState:LongWord;`	Touch device state (eg TOUCH_STATE_ENABLED)
`DeviceStart:TTouchDeviceStart;`	A Device specific DeviceStart method implementing the standard Touch device interface (Mandatory)
`DeviceStop:TTouchDeviceStop;`	A Device specific DeviceStop method implementing the standard Touch device interface (Mandatory)
`DevicePeek:TTouchDevicePeek;`	A Device specific DevicePeek method implementing a standard Touch device interface (Or nil if the default method is suitable)
`DeviceRead:TTouchDeviceRead;`	A Device specific DeviceRead method implementing a standard Touch device interface (Or nil if the default method is suitable)
`DeviceWrite:TTouchDeviceWrite;`	A Device specific DeviceWrite method implementing a standard Touch device interface (Or nil if the default method is suitable)
`DeviceFlush:TTouchDeviceFlush;`	A Device specific DeviceFlush method implementing a standard Touch device interface (Or nil if the default method is suitable)
`DeviceUpdate:TTouchDeviceUpdate;`	A Device specific DeviceUpdate method implementing a standard Touch device interface (Or nil if the default method is suitable)
`DeviceControl:TTouchDeviceControl;`	A Device specific DeviceControl method implementing a standard Touch device interface (Or nil if the default method is suitable)
`DeviceGetProperties:TTouchDeviceGetProperties;`	A Device specific DeviceGetProperties method implementing a standard Touch device interface (Or nil if the default method is suitable)
Driver Properties
`Lock:TMutexHandle;`	Device lock
`Buffer:TTouchBuffer;`	Touch input buffer
`Properties:TTouchProperties;`	Device properties
Statistics Properties
`ReceiveCount:LongWord;`
`ReceiveErrors:LongWord;`
`BufferOverruns:LongWord;`
Internal Properties
`Prev:PTouchDevice;`	Previous entry in Touch device table
`Next:PTouchDevice;`	Next entry in Touch device table

Public variables

Touch logging

`TOUCH_DEFAULT_LOG_LEVEL:LongWord = TOUCH_LOG_LEVEL_DEBUG;`	Minimum level for Touch messages. Only messages with level greater than or equal to this will be printed.

`TOUCH_LOG_ENABLED:Boolean;`

Function declarations

Initialization functions

procedure TouchInit;

Description: Initialize the Touch unit and Touch device table

Note	Called only during system startup

Touch functions

function TouchDeviceStart(Touch:PTouchDevice):LongWord;

Description: Start the specified Touch device ready for receiving events

Touch	The Touch device to start
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDeviceStop(Touch:PTouchDevice):LongWord;

Description: Stop the specified Touch device and terminate receiving events

Touch	The Touch device to stop
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDevicePeek(Touch:PTouchDevice):LongWord;

Description: Peek at the buffer of the specified touch device to see if any data packets are ready

Touch	The Touch device to peek at
Return	ERROR_SUCCESS if packets are ready, ERROR_NO_MORE_ITEMS if not or another error code on failure.

function TouchDeviceRead(Touch:PTouchDevice; Buffer:Pointer; Size,Flags:LongWord; var Count:LongWord):LongWord;

Description: Read touch data packets from the buffer of the specified touch device

Touch	The Touch device to read from
Buffer	Pointer to a buffer to copy the touch data packets to
Size	The size of the buffer in bytes (Must be at least TTouchData or greater)
Flags	The flags for the behaviour of the read (eg TOUCH_FLAG_NON_BLOCK)
Count	The number of touch data packets copied to the buffer
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDeviceWrite(Touch:PTouchDevice; Buffer:Pointer; Size,Count:LongWord):LongWord;

Description: Write touch data packets to the buffer of the specified touch device

Touch	The Touch device to write to
Buffer	Pointer to a buffer to copy the touch data packets from
Size	The size of the buffer in bytes (Must be at least TTouchData or greater)
Count	The number of touch data packets to copy from the buffer
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDeviceFlush(Touch:PTouchDevice):LongWord;

Description: Flush the contents of the buffer of the specified touch device

Touch	The Touch device to flush
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDeviceUpdate(Touch:PTouchDevice):LongWord;

Description: Request the specified touch device to update the current configuration

Touch	The Touch device to update
Return	ERROR_SUCCESS if completed or another error code on failure
Note	Items updated can include rotation, maximum X and Y and flags (If supported)

function TouchDeviceControl(Touch:PTouchDevice; Request:Integer; Argument1:PtrUInt; var Argument2:PtrUInt):LongWord;

Description: Perform a control request on the specified touch device

Touch	The Touch device to control
Request	The request code for the operation (eg TOUCH_CONTROL_GET_FLAG)
Argument1	The first argument for the operation (Dependent on request code)
Argument2	The second argument for the operation (Dependent on request code)
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDeviceProperties(Touch:PTouchDevice; Properties:PTouchProperties):LongWord; inline;

Description: Get the properties for the specified Touch device

Touch	The Touch device to get properties from
Properties	Pointer to a TTouchProperties structure to fill in
Return	ERROR_SUCCESS if completed or another error code on failure
Note	Replaced by TouchDeviceGetProperties for consistency

function TouchDeviceGetProperties(Touch:PTouchDevice;Properties:PTouchProperties):LongWord;

Description: Get the properties for the specified Touch device

Touch	The Touch device to get properties from
Properties	Pointer to a TTouchProperties structure to fill in
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDeviceCreate:PTouchDevice;

Description: Create a new Touch device entry

Return	Pointer to new Touch device entry or nil if Touch device could not be created

function TouchDeviceCreateEx(Size:LongWord):PTouchDevice;

Description: Create a new Touch device entry

Size	Size in bytes to allocate for new Touch device (Including the Touch device entry)
Return	Pointer to new Touch device entry or nil if Touch device could not be created

function TouchDeviceDestroy(Touch:PTouchDevice):LongWord;

Description: Destroy an existing Touch device entry

Touch	The Touch device to destroy
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDeviceRegister(Touch:PTouchDevice):LongWord;

Description: Register a new Touch device in the Touch device table

Touch	The Touch device to register
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDeviceDeregister(Touch:PTouchDevice):LongWord;

Description: Deregister an Touch device from the Touch device table

Touch	The Touch device to dregister
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDeviceFind(TouchId:LongWord):PTouchDevice;

Description: Find a Touch device by ID in the Touch device table

TouchId	The ID number of the Touch device to find
Return	Pointer to Touch device entry or nil if not found

function TouchDeviceFindByName(const Name:String):PTouchDevice; inline;

Description: Find a Touch device by name in the device table

Name	The name of the Touch device to find (eg Touch0)
Return	Pointer to Touch device entry or nil if not found

function TouchDeviceFindByDescription(const Description:String):PTouchDevice; inline;

Description: Find a Touch device by description in the device table

Description	The description of the Touch to find (eg USB Touchscreen)
Return	Pointer to Touch device entry or nil if not found

function TouchDeviceEnumerate(Callback:TTouchEnumerate; Data:Pointer):LongWord;

Description: Enumerate all Touch devices in the Touch device table

Callback	The callback function to call for each Touch device in the table
Data	A private data pointer to pass to callback for each Touch device in the table
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDeviceNotification(Touch:PTouchDevice; Callback:TTouchNotification; Data:Pointer; Notification,Flags:LongWord):LongWord;

Description: Register a notification for Touch device changes

Touch	The Touch device to notify changes for (Optional, pass nil for all Touch devices)
Callback	The function to call when a notification event occurs
Data	A private data pointer to pass to callback when a notification event occurs
Notification	The events to register for notification of (eg DEVICE_NOTIFICATION_REGISTER)
Flags	The flags to control the notification (eg NOTIFIER_FLAG_WORKER)
Return	ERROR_SUCCESS if completed or another error code on failure

Touch helper functions

function TouchGetCount:LongWord; inline;

Description: Get the current Touch device count

Return	The number of Touch devices

function TouchDeviceGetDefault:PTouchDevice; inline;

Description: Get the current default Touch device

Return	Pointer to default Touch device entry

function TouchDeviceSetDefault(Touch:PTouchDevice):LongWord;

Description: Set the current default Touch device

Touch	The Touch device to set as default
Return	ERROR_SUCCESS if completed or another error code on failure

function TouchDeviceCheck(Touch:PTouchDevice):PTouchDevice;

Description: Check if the supplied Touch device is in the Touch device table

Touch	The Touch device to check
Return	Pointer to Touch device entry or nil if not found

function TouchDeviceTypeToString(TouchType:LongWord):String;

Description: Return a string describing the Touch device type (eg TOUCH_TYPE_CAPACITIVE)

Note	None documented

function TouchDeviceStateToString(TouchState:LongWord):String;

Description: Return a string describing the Touch device state (eg TOUCH_STATE_ENABLED)

Note	None documented

function TouchDeviceRotationToString(Rotation:LongWord):String;

Description: Return a string describing the supplied touch rotation value

Note	None documented

function TouchDeviceResolveRotation(ARotation:LongWord):LongWord;

Description: Resolve a value of 0, 90, 180 or 270 to a touch rotation constant (eg TOUCH_ROTATION_180)

Note	Also accepts passing the touch rotation constant values directly

function TouchDeviceSetCallback(Touch:PTouchDevice; Event:TTouchEvent; Parameter:Pointer):LongWord;

Description: Set the event callback function for the specified touch device

Touch	The touch device to set the event callback for
Event	The event callback function to be called when touch data is received
Parameter	A pointer to private data to be passed to the callback with each event
Return	ERROR_SUCCESS if completed or another error code on failure
Note	This function also clears the TOUCH_FLAG_MOUSE_DATA flag because the event callback is not compatible with receiving touch events as mouse data

function TouchInsertData(Touch:PTouchDevice; Data:PTouchData; Signal:Boolean):LongWord;

Description: Insert a TTouchData entry into the touch device buffer

Touch	The touch device to insert data for
Data	The TTouchData entry to insert
Signal	If True then signal that new data is available in the buffer
Return	ERROR_SUCCESS if completed or another error code on failure
Note	Caller must hold the touch device lock

procedure TouchLog(Level:LongWord; Touch:PTouchDevice; const AText:String);