acid-drop/lib/TFT_eSPI/examples/PNG Images/LittleFS_PNG/LittleFS_PNG.ino
2024-05-23 18:42:03 -04:00

100 lines
3.5 KiB
C++

// This example if for processors with LittleFS capability (e.g. RP2040,
// ESP32, ESP8266). It renders a png file that is stored in LittleFS
// using the PNGdec library (available via library manager).
// The test image is in the sketch "data" folder (press Ctrl+K to see it).
// You must upload the image to LittleFS using the Arduino IDE Tools Data
// Upload menu option (you may need to install extra tools for that).
// Don't forget to use the Arduino IDE Tools menu to allocate a LittleFS
// memory partition before uploading the sketch and data!
#include <LittleFS.h>
#define FileSys LittleFS
// Include the PNG decoder library
#include <PNGdec.h>
PNG png;
#define MAX_IMAGE_WIDTH 240 // Adjust for your images
int16_t xpos = 0;
int16_t ypos = 0;
// Include the TFT library https://github.com/Bodmer/TFT_eSPI
#include "SPI.h"
#include <TFT_eSPI.h> // Hardware-specific library
TFT_eSPI tft = TFT_eSPI(); // Invoke custom library
//====================================================================================
// Setup
//====================================================================================
void setup()
{
Serial.begin(115200);
Serial.println("\n\n Using the PNGdec library");
// Initialise FS
if (!FileSys.begin()) {
Serial.println("LittleFS initialisation failed!");
while (1) yield(); // Stay here twiddling thumbs waiting
}
// Initialise the TFT
tft.begin();
tft.fillScreen(TFT_BLACK);
Serial.println("\r\nInitialisation done.");
}
//====================================================================================
// Loop
//====================================================================================
void loop()
{
// Scan LittleFS and load any *.png files
File root = LittleFS.open("/", "r");
while (File file = root.openNextFile()) {
String strname = file.name();
strname = "/" + strname;
Serial.println(file.name());
// If it is not a directory and filename ends in .png then load it
if (!file.isDirectory() && strname.endsWith(".png")) {
// Pass support callback function names to library
int16_t rc = png.open(strname.c_str(), pngOpen, pngClose, pngRead, pngSeek, pngDraw);
if (rc == PNG_SUCCESS) {
tft.startWrite();
Serial.printf("image specs: (%d x %d), %d bpp, pixel type: %d\n", png.getWidth(), png.getHeight(), png.getBpp(), png.getPixelType());
uint32_t dt = millis();
if (png.getWidth() > MAX_IMAGE_WIDTH) {
Serial.println("Image too wide for allocated line buffer size!");
}
else {
rc = png.decode(NULL, 0);
png.close();
}
tft.endWrite();
// How long did rendering take...
Serial.print(millis()-dt); Serial.println("ms");
}
}
delay(3000);
tft.fillScreen(random(0x10000));
}
}
//=========================================v==========================================
// pngDraw
//====================================================================================
// This next function will be called during decoding of the png file to
// render each image line to the TFT. If you use a different TFT library
// you will need to adapt this function to suit.
// Callback function to draw pixels to the display
void pngDraw(PNGDRAW *pDraw) {
uint16_t lineBuffer[MAX_IMAGE_WIDTH];
png.getLineAsRGB565(pDraw, lineBuffer, PNG_RGB565_BIG_ENDIAN, 0xffffffff);
tft.pushImage(xpos, ypos + pDraw->y, pDraw->iWidth, 1, lineBuffer);
}