lvgl_esp32_drivers/lvgl_touch/L58/include/L58Touch.h

// This is the first experimental Touch component for the LILYGO EPD47 touch overlay
// NOTE: As in LVGL we cannot use blocking functions this is a variation of original library here:
//       https://github.com/martinberlin/FT6X36-IDF
// More info about this epaper: 
// https://github.com/martinberlin/cale-idf/wiki/Model-parallel-ED047TC1.h
#include <stdint.h>
//#include <cstdlib>
#include "driver/gpio.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/semphr.h"
#include <stdio.h>
#include "esp_log.h"
#include "driver/i2c.h"
#include "sdkconfig.h"
#include "esp_idf_version.h"
#ifndef touch_ttgo_h
#define touch_ttgo_h
// I2C Constants
#define I2C_MASTER_TX_BUF_DISABLE 0                           /*!< I2C master doesn't need buffer */
#define I2C_MASTER_RX_BUF_DISABLE 0                           /*!< I2C master doesn't need buffer */

#define ACK_CHECK_EN 0x1                        /*!< I2C master will check ack from slave*/
#define ACK_CHECK_DIS 0x0                       /*!< I2C master will not check ack from slave */
#define ACK_VAL 0x0                             /*!< I2C ack value */
#define NACK_VAL 0x1                            /*!< I2C nack value */

#define L58_ADDR	0x5A

// Note: We still could not read proper events, so we simulate Tap
	enum class TEvent
	{
		None,
		TouchStart,
		TouchMove,
		TouchEnd,
		Tap
	};

	struct TPoint
	{
		uint16_t x;
		uint16_t y;
		uint8_t event;
	};

class L58Touch
{

	typedef struct {
		uint8_t id;
        uint8_t event;
        uint16_t x;
        uint16_t y;
    } TouchData_t;

	

public:
    // TwoWire * wire will be replaced by ESP-IDF https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/peripherals/i2c.html
	L58Touch(int8_t intPin);
	~L58Touch();

	bool begin(uint16_t width = 0, uint16_t height = 0);
	void registerTouchHandler(void(*fn)(TPoint point, TEvent e));
	uint8_t touched();
	TPoint loop();
	TPoint processTouch();
	// Helper functions to make the touch display aware
	void setRotation(uint8_t rotation);
	void setTouchWidth(uint16_t width);
	void setTouchHeight(uint16_t height);
	// Pending implementation. How much x->touch y↓touch is placed (In case is smaller than display)
	void setXoffset(uint16_t x_offset);
	void setYoffset(uint16_t y_offset);
	void sleep();
	// Smart template from EPD to swap x,y:
    template <typename T> static inline void
    swap(T& a, T& b)
    {
      T t = a;
      a = b;
      b = t;
    }

	void(*_touchHandler)(TPoint point, TEvent e) = nullptr;
	TouchData_t data[5];
	// Tap detection is enabled by default
	bool tapDetectionEnabled = true;
	// Only if the time difference between press and release is minor than this milliseconds a Tap even is triggered
	uint16_t tapDetectionMillisDiff = 100;
	
private:
	TPoint scanPoint();
	void writeRegister8(uint8_t reg, uint8_t val);
	void writeData(uint8_t *data, int len);
	void readBytes(uint8_t *data, int len);
	uint8_t readRegister8(uint8_t reg, uint8_t *data_buf);
	void fireEvent(TPoint point, TEvent e);
	uint8_t read8(uint8_t regName);
	void clearFlags();

	static L58Touch * _instance;
	uint8_t _intPin;
	
	// Make touch rotation aware:
	uint8_t _rotation = 0;
	uint16_t _touch_width = 0;
	uint16_t _touch_height = 0;

	uint8_t _touches;
	uint16_t _touchX[2], _touchY[2], _touchEvent[2];
	TPoint _points[10];
	TPoint _point;
	uint8_t _pointIdx = 0;
	unsigned long _touchStartTime = 0;
	unsigned long _touchEndTime = 0;
    uint8_t lastEvent = 3; // No event
	uint16_t lastX = 0;
	uint16_t lastY = 0;
	bool _dragMode = false;
	const uint8_t maxDeviation = 5;
};

#endif