spreLgfxTouch

spreLgfxTouch is an Arduino library designed specifically for the Sony Spresense platform. It provides functionality to display JPEG images on an ILI9341 display and handle touch input with an XPT2046 touch controller. The library is built on top of LovyanGFX for efficient graphics rendering and XPT2046_Touchscreen for touch input.

Features

• Display JPEG images on ILI9341-based displays.
• Handle touch input with XPT2046 touch controller.
• Support for 16-bit and 8-bit color depth.
• Optimized for Sony Spresense.
• Smooth frame rate display and basic touch drawing functions.

Requirements

Before using spreLgfxTouch, ensure you have the following libraries installed:

• LovyanGFX - High-performance graphics library for Arduino.
• XPT2046_Touchscreen - Touchscreen controller library for XPT2046.

Both libraries will be automatically installed if you install spreLgfxTouch through the Arduino Library Manager.

Installation

Using Arduino Library Manager

1. Open the Arduino IDE.
2. Go to Sketch > Include Library > Manage Libraries...
3. In the Library Manager, search for spreLgfxTouch.
4. Click Install.

Manual Installation

1. Download the spreLgfxTouch library from the GitHub repository.
2. Extract the downloaded ZIP file.
3. Copy the spreLgfxTouch folder into the libraries folder of your Arduino directory (usually Documents/Arduino/libraries).

How to Use

Basic Example

The following example demonstrates how to display a JPEG image on the screen and handle touch input:

//
//  name          : spreLgfxTouch.ino
//  date/author   : 2024/10/23 chrmlinux03
//  update/author : 2024/10/23 chrmlinux03
//

#include <SDHCI.h>
#include <File.h>
SDClass SD;
File myFile;

#include "spreLGFXLib.hpp"
#include "spreTouchLib.hpp"

//===================================
// setup
//===================================
void setup(void) {
  Serial.begin(115200);
  if (!SD.begin()) {
    Serial.println("ERROR: SD card");
    while (1);
  }
  setupLGFX(DEPTH_16BIT, ROT90);
  setupTouch(_w, _h, ROT90, false);
}

//===================================
// loop
//===================================
void loop(void) {
  drawJpgToMemory(&spr, "/sample.jpg");
  drawCorner(&spr, _hw/2, _hh/2, _hw, _hh, TFT_WHITE);
  int tx, ty, tz;
  if (isTouch(&tx, &ty, &tz)) {
    spr.drawLine(tx, 0, tx, _h, TFT_GREEN);
    spr.drawLine(0, ty, _w, ty, TFT_BLUE);
    spr.drawCircle(tx, ty, tz / 100, TFT_RED);
  }
  drawAst(&spr, 0, _h - 8, TFT_BLACK, TFT_WHITE);
  spr.pushSprite(&lcd, 0, 0);
}

Key Functions

• setupLGFX(int16_t cdep, int16_t rot): Initializes the display with the specified color depth (cdep) and rotation (rot).
• setupTouch(int16_t w, int16_t h, int16_t r, bool swap): Sets up the touch controller with the screen dimensions (w, h), rotation (r), and whether to swap the touch axes (swap).
• isTouch(int *tx, int *ty, int *tz): Detects if the screen is being touched and returns the touch coordinates (tx, ty) and pressure (tz).
• drawJpgToMemory(LGFX_Sprite *dst, const char *fname): Draws a JPEG image from the SD card to the specified sprite (dst).

Dependencies

This library depends on the following:

• LovyanGFX: For fast graphics rendering on the ILI9341 display.
• XPT2046_Touchscreen: For touch input handling.

These dependencies will be automatically installed when using the Arduino Library Manager.

Hardware Setup

• Display: ILI9341-based SPI display (240x320 resolution).
• Touch Controller: XPT2046 touch controller via SPI.
• Microcontroller: Sony Spresense main board.

Wiring

Component	Spresense Pin	Display/Touch Pin
SPI SCLK	PIN_SPI_SCK	SCK
SPI MOSI	PIN_SPI_MOSI	MOSI
SPI MISO	PIN_SPI_MISO	MISO
SPI CS (Display)	10	CS (Display)
SPI DC (Display)	9	DC
SPI RST	8	RST
SPI CS (Touch)	7	CS (Touch)

License

This library is licensed under the MIT License. See the LICENSE file for details.