From 2e84218ecbd5105dd0007268d87de70f9d3529fc Mon Sep 17 00:00:00 2001
From: Bodmer <bodmer@anola.net>
Date: Thu, 21 Dec 2017 23:16:11 +0000
Subject: [PATCH] Add touch pressure hysterisis and user defined sensitivity

getTouch accepts a third optional pressure threshold, default is 600,
increasing means harder presses are needed.
getTouch(uint16_t *x, uint16_t *y, uint16_t threshold = 600);
---
 TFT_eSPI.cpp       | 26 ++++++++++++++++++++------
 TFT_eSPI.h         |  4 +++-
 library.json       |  2 +-
 library.properties |  2 +-
 4 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/TFT_eSPI.cpp b/TFT_eSPI.cpp
index 641874a..15578d5 100644
--- a/TFT_eSPI.cpp
+++ b/TFT_eSPI.cpp
@@ -4114,10 +4114,22 @@ uint8_t TFT_eSPI::validTouch(uint16_t *x, uint16_t *y, uint16_t threshold){
 ** Description:             read callibrated position. Return false if not pressed. 
 ***************************************************************************************/
 #define Z_THRESHOLD 350 // Touch pressure threshold for validating touches
-uint8_t TFT_eSPI::getTouch(uint16_t *x, uint16_t *y){
+uint8_t TFT_eSPI::getTouch(uint16_t *x, uint16_t *y, uint16_t threshold){
   uint16_t x_tmp, y_tmp, xx, yy;
   
-  if(!validTouch(&x_tmp, &y_tmp, Z_THRESHOLD)) return false;
+  if (threshold<20) threshold = 20;
+  if (_pressTime > millis()) threshold=20;
+
+  byte n = 5;
+  byte valid = 0;
+  while (n--)
+  {
+    if (validTouch(&x_tmp, &y_tmp, threshold)) valid++;;
+  }
+
+  if (valid<1) { _pressTime = 0; return false; }
+  
+  _pressTime = millis() + 50;
 
   if(!touchCalibration_rotate){
     xx=(x_tmp-touchCalibration_x0)*_width/touchCalibration_x1;
@@ -4135,11 +4147,13 @@ uint8_t TFT_eSPI::getTouch(uint16_t *x, uint16_t *y){
       yy = _height - yy;
   }
 
-  if (xx >= _width || yy >= _height) return false;
+  if (xx >= _width || yy >= _height) return valid;
 
-  *x = xx;
-  *y = yy;
-  return true;
+  _pressX = xx;
+  _pressY = yy;
+  *x = _pressX;
+  *y = _pressY;
+  return valid;
 }
 
 /***************************************************************************************
diff --git a/TFT_eSPI.h b/TFT_eSPI.h
index ae7f3c0..c291c92 100644
--- a/TFT_eSPI.h
+++ b/TFT_eSPI.h
@@ -458,7 +458,7 @@ class TFT_eSPI : public Print {
            // These are associated with the Touch Screen handlers
   uint8_t  getTouchRaw(uint16_t *x, uint16_t *y);
   uint16_t getTouchRawZ(void);
-  uint8_t  getTouch(uint16_t *x, uint16_t *y);
+  uint8_t  getTouch(uint16_t *x, uint16_t *y, uint16_t threshold = 600);
 
   void     calibrateTouch(uint16_t *data, uint32_t color_fg, uint32_t color_bg, uint8_t size);
   void     setTouch(uint16_t *data);
@@ -488,6 +488,8 @@ class TFT_eSPI : public Print {
            // Initialise with example calibration values so processor does not crash if setTouch() not called in setup()
   uint16_t touchCalibration_x0 = 300, touchCalibration_x1 = 3600, touchCalibration_y0 = 300, touchCalibration_y1 = 3600;
   uint8_t  touchCalibration_rotate = 1, touchCalibration_invert_x = 2, touchCalibration_invert_y = 0;
+  uint32_t _pressTime;
+  uint16_t _pressX, _pressY;
 
  protected:
 
diff --git a/library.json b/library.json
index 1de946d..d189858 100644
--- a/library.json
+++ b/library.json
@@ -1,6 +1,6 @@
 {
   "name": "TFT_eSPI",
-  "version": "0.17.19",
+  "version": "0.17.20",
   "keywords": "TFT, ESP8266, NodeMCU, ESP32, ILI9341, ST7735, ILI9163, S6D02A1, ILI9486",
   "description": "A TFT SPI graphics library for ESP8266",
   "repository":
diff --git a/library.properties b/library.properties
index 59804c6..61ea335 100644
--- a/library.properties
+++ b/library.properties
@@ -1,5 +1,5 @@
 name=TFT_eSPI
-version=0.17.19
+version=0.17.20
 author=Bodmer
 maintainer=Bodmer
 sentence=A fast TFT library for ESP8266 processors and the Arduino IDE