TouchDriver Class Reference

Base class for touch controllers. More...

#include <TouchDriverCommon.h>

Inheritance diagram for TouchDriver:

Collaboration diagram for TouchDriver:

Public Member Functions
virtual	~TouchDriver ()=default
virtual bool	begin ()=0
	Initialize the controller.
virtual bool	isTouched ()=0
	Return whether the panel currently appears touched.
virtual bool	getPoint (Point &outPoint)=0
	Read the current touch point.
virtual bool	getSecondPoint (Point &outPoint)
	Read a second, simultaneous touch point, for multi-touch gestures (pinch/rotate).
void	setRotation (Rotation rotation)
Rotation	getRotation () const
bool	setCalibration (const CalibrationData &cal)
	Set and validate calibration.
const CalibrationData &	getCalibration () const
bool	hasCalibration () const

Protected Member Functions
Point	mapCoordinates (int16_t rawX, int16_t rawY, uint16_t pressure=255) const
	Convert raw controller coordinates into logical display space.

Static Protected Member Functions
static bool	validateCalibration (const CalibrationData &cal)
static int32_t	clamp32 (int32_t value, int32_t minimum, int32_t maximum)
	Clamp an integer to an inclusive range.
static int32_t	mapRange (int32_t value, int32_t inMin, int32_t inMax, int32_t outMin, int32_t outMax)
	Map an integer from one range to another.

Protected Attributes
Rotation	rotation_ = Rotation::Deg0
CalibrationData	calibration_
bool	hasCalibration_ = false

Detailed Description

Base class for touch controllers.

Constructor & Destructor Documentation

~TouchDriver()

virtual ~TouchDriver ( )

virtualdefault

Member Function Documentation

begin()

virtual bool begin ( )

pure virtual

Initialize the controller.

The driver does NOT initialize the SPI/I2C bus itself. The application is responsible for calling Wire.begin(), SPI.begin(), and configuring any board-specific bus pins.

Implemented in TouchDriverSTM32F723Discovery, TouchDriverXPT2046, TouchDriverBitBang, TouchDriverFT6236, TouchDriverCST816S, TouchDriverGT911, TouchDriverSDL, and TouchDriverTFTeSPI.

clamp32()

static int32_t clamp32 ( int32_t  value, int32_t  minimum, int32_t  maximum  )

inlinestaticprotected

Clamp an integer to an inclusive range.

getCalibration()

const CalibrationData & getCalibration ( ) const

inline

getPoint()

virtual bool getPoint ( Point &  outPoint )

pure virtual

Read the current touch point.

Returns

true if a valid touch point was obtained.

Implemented in TouchDriverSTM32F723Discovery, TouchDriverXPT2046, TouchDriverBitBang, TouchDriverFT6236, TouchDriverCST816S, TouchDriverGT911, TouchDriverSDL, and TouchDriverTFTeSPI.

getRotation()

Rotation getRotation ( ) const

inline

getSecondPoint()

virtual bool getSecondPoint ( Point &  outPoint )

inlinevirtual

Read a second, simultaneous touch point, for multi-touch gestures (pinch/rotate).

Returns false by default. Only override this if the underlying controller can genuinely report two simultaneous touches - none of the drivers built into this library can (XPT2046 is a resistive, inherently single-touch controller; CST816S/FT6236 are single-touch capacitive parts), so pinch/rotate gestures built on top of this will not fire against them.

Reimplemented in TouchDriverSTM32F723Discovery, and TouchDriverGT911.

hasCalibration()

bool hasCalibration ( ) const

inline

isTouched()

virtual bool isTouched ( )

pure virtual

Return whether the panel currently appears touched.

For controllers without an IRQ pin this may perform a controller read.

Implemented in TouchDriverSTM32F723Discovery, TouchDriverXPT2046, TouchDriverBitBang, TouchDriverFT6236, TouchDriverCST816S, TouchDriverGT911, TouchDriverSDL, and TouchDriverTFTeSPI.

mapCoordinates()

Point mapCoordinates ( int16_t  rawX, int16_t  rawY, uint16_t  pressure = 255  ) const

inlineprotected

Convert raw controller coordinates into logical display space.

Processing order:

raw coordinates -> inversion -> independent X/Y calibration -> swap XY -> display rotation

This order is important. In particular, swapping raw X/Y before calibration would incorrectly apply the X calibration range to Y and vice versa.

mapRange()

static int32_t mapRange ( int32_t  value, int32_t  inMin, int32_t  inMax, int32_t  outMin, int32_t  outMax  )

inlinestaticprotected

Map an integer from one range to another.

Unlike Arduino's map(), this function:

• uses 64-bit intermediate arithmetic
• explicitly handles invalid ranges
• avoids accidental overflow for normal touch-controller ranges

setCalibration()

bool setCalibration ( const CalibrationData &  cal )

inline

Set and validate calibration.

Returns

true if the calibration is valid.

setRotation()

void setRotation ( Rotation  rotation )

inline

validateCalibration()

static bool validateCalibration ( const CalibrationData &  cal )

inlinestaticprotected

Member Data Documentation

calibration_

CalibrationData calibration_

protected

hasCalibration_

bool hasCalibration_ = false

protected

rotation_

Rotation rotation_ = Rotation::Deg0

protected

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The documentation for this class was generated from the following file:

• src/TinyGPU/Input/TouchDriverCommon.h