GfxUi.cpp

/**The MIT License (MIT)
Copyright (c) 2015 by Daniel Eichhorn
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
See more at http://blog.squix.ch
*/

// Adapted by Bodmer to use the TFT_eSPI library: https://github.com/Bodmer/TFT_eSPI
// Functions no longer needed weeded out, Jpeg decoder functions added and updated
// drawBMP() updated to buffer input and output pixels and avoid slow seeks

#include "GfxUi.h"
#include <LittleFS.h>  // this project mounts LittleFS only — drawBmp() below used to
                        // reference the (never-mounted) SPIFFS object instead

GfxUi::GfxUi(TFT_eSPI *tft) {
  _tft = tft;
}

void GfxUi::drawProgressBar(uint16_t x0, uint16_t y0, uint16_t w, uint16_t h, uint8_t percentage, uint16_t frameColor, uint16_t barColor) {
  if (percentage == 0) {
    _tft->fillRoundRect(x0, y0, w, h, 3, TFT_BLACK);
  }
  uint8_t margin = 2;
  uint16_t barHeight = h - 2 * margin;
  uint16_t barWidth = w - 2 * margin;
  _tft->drawRoundRect(x0, y0, w, h, 3, frameColor);
  _tft->fillRect(x0 + margin, y0 + margin, barWidth * percentage / 100.0, barHeight, barColor);
}

// Bodmer's streamlined x2 faster "no seek" version
void GfxUi::drawBmp(String filename, uint16_t x, uint16_t y)
{

  if ((x >= _tft->width()) || (y >= _tft->height())) return;

  fs::File bmpFS;

  // Check file exists and open it
  // Serial.println(filename);

  // Note: ESP32 passes "open" test even if file does not exist, whereas ESP8266 returns NULL
  if ( !LittleFS.exists(filename) )
  {
    Serial.println(F(" File not found")); // Can comment out if not needed
    return;
  }

  // Open requested file
  bmpFS = LittleFS.open(filename, "r");

  uint32_t seekOffset;
  uint16_t w, h, row, col;
  uint8_t  r, g, b;

  if (read16(bmpFS) == 0x4D42)
  {
    read32(bmpFS);
    read32(bmpFS);
    seekOffset = read32(bmpFS);
    read32(bmpFS);
    w = read32(bmpFS);
    h = read32(bmpFS);

    if ((read16(bmpFS) == 1) && (read16(bmpFS) == 24) && (read32(bmpFS) == 0))
    {
      y += h - 1;

      _tft->setSwapBytes(true);
      bmpFS.seek(seekOffset);

      // Calculate padding to avoid seek
      uint16_t padding = (4 - ((w * 3) & 3)) & 3;
      uint8_t lineBuffer[w * 3 + padding];

      for (row = 0; row < h; row++) {
        
        bmpFS.read(lineBuffer, sizeof(lineBuffer));
        uint8_t*  bptr = lineBuffer;
        uint16_t* tptr = (uint16_t*)lineBuffer;
        // Convert 24 to 16 bit colours using the same line buffer for results
        for (uint16_t col = 0; col < w; col++)
        {
          b = *bptr++;
          g = *bptr++;
          r = *bptr++;
          *tptr++ = ((r & 0xF8) << 8) | ((g & 0xFC) << 3) | (b >> 3);
        }

        // Push the pixel row to screen, pushImage will crop the line if needed
        // y is decremented as the BMP image is drawn bottom up
        _tft->pushImage(x, y--, w, 1, (uint16_t*)lineBuffer);
      }
    }
    else Serial.println("BMP format not recognized.");
  }
  bmpFS.close();
}

// These read 16- and 32-bit types from the SD card file.
// BMP data is stored little-endian, Arduino is little-endian too.
// May need to reverse subscript order if porting elsewhere.

uint16_t GfxUi::read16(fs::File &f) {
  uint16_t result;
  ((uint8_t *)&result)[0] = f.read(); // LSB
  ((uint8_t *)&result)[1] = f.read(); // MSB
  return result;
}

uint32_t GfxUi::read32(fs::File &f) {
  uint32_t result;
  ((uint8_t *)&result)[0] = f.read(); // LSB
  ((uint8_t *)&result)[1] = f.read();
  ((uint8_t *)&result)[2] = f.read();
  ((uint8_t *)&result)[3] = f.read(); // MSB
  return result;
}

/*====================================================================================
  This sketch support functions to render the Jpeg images.

  Created by Bodmer 15th Jan 2017
  ==================================================================================*/

// Return the minimum of two values a and b
#define minimum(a,b)     (((a) < (b)) ? (a) : (b))

#define USE_SPI_BUFFER // Comment out to use slower 16 bit pushColor()

//====================================================================================
//   Opens the image file and prime the Jpeg decoder
//====================================================================================
void GfxUi::drawJpeg(String filename, int xpos, int ypos) {

  // Serial.println("===========================");
  // Serial.print("Drawing file: "); Serial.println(filename);
  // Serial.println("===========================");

  // Open the named file just to confirm it exists and is readable — this handle
  // isn't passed to the decoder below (that call opens the file again itself).
  fs::File jpegFile = LittleFS.open( filename, "r");   // this project mounts LittleFS only
  //  File jpegFile = SD.open( filename, FILE_READ);  // or, file handle reference for SD library

  if ( !jpegFile ) {
    Serial.print("ERROR: File \""); Serial.print(filename); Serial.println ("\" not found!");
    return;
  }
  jpegFile.close();

  // Use one of the three following methods to initialise the decoder:
  //boolean decoded = JpegDec.decodeFsFile(jpegFile); // Pass a SPIFFS file handle to the decoder,
  //boolean decoded = JpegDec.decodeSdFile(jpegFile); // or pass the SD file handle to the decoder,
  boolean decoded = JpegDec.decodeFsFile(filename);  // or pass the filename (leading / distinguishes SPIFFS files)
                                   // Note: the filename can be a String or character array type
  if (decoded) {
    // print information about the image to the serial port
    jpegInfo();

    // render the image onto the screen at given coordinates
    jpegRender(xpos, ypos);
  }
  else {
    Serial.println("Jpeg file format not supported!");
  }
}

//====================================================================================
//   Decode and render the Jpeg image onto the TFT screen
//====================================================================================
void GfxUi::jpegRender(int xpos, int ypos) {

  // retrieve infomration about the image
  uint16_t  *pImg;
  uint16_t mcu_w = JpegDec.MCUWidth;
  uint16_t mcu_h = JpegDec.MCUHeight;
  uint32_t max_x = JpegDec.width;
  uint32_t max_y = JpegDec.height;

  // Jpeg images are draw as a set of image block (tiles) called Minimum Coding Units (MCUs)
  // Typically these MCUs are 16x16 pixel blocks
  // Determine the width and height of the right and bottom edge image blocks
  uint32_t min_w = minimum(mcu_w, max_x % mcu_w);
  uint32_t min_h = minimum(mcu_h, max_y % mcu_h);

  // save the current image block size
  uint32_t win_w = mcu_w;
  uint32_t win_h = mcu_h;

  // record the current time so we can measure how long it takes to draw an image
  uint32_t drawTime = millis();

  // save the coordinate of the right and bottom edges to assist image cropping
  // to the screen size
  max_x += xpos;
  max_y += ypos;

  // read each MCU block until there are no more
#ifdef USE_SPI_BUFFER
  while( JpegDec.readSwappedBytes()){ // Swap byte order so the SPI buffer can be used
#else
  while ( JpegDec.read()) { // Normal byte order read
#endif
    // save a pointer to the image block
    pImg = JpegDec.pImage;

    // calculate where the image block should be drawn on the screen
    int mcu_x = JpegDec.MCUx * mcu_w + xpos;
    int mcu_y = JpegDec.MCUy * mcu_h + ypos;

    // check if the image block size needs to be changed for the right edge
    if (mcu_x + mcu_w <= max_x) win_w = mcu_w;
    else win_w = min_w;

    // check if the image block size needs to be changed for the bottom edge
    if (mcu_y + mcu_h <= max_y) win_h = mcu_h;
    else win_h = min_h;

    // copy pixels into a contiguous block
    if (win_w != mcu_w)
    {
      uint16_t *cImg;
      int p = 0;
      cImg = pImg + win_w;
      for (int h = 1; h < win_h; h++)
      {
        p += mcu_w;
        for (int w = 0; w < win_w; w++)
        {
          *cImg = *(pImg + w + p);
          cImg++;
        }
      }
    }

    // draw image MCU block only if it will fit on the screen
    if ( ( mcu_x + win_w) <= _tft->width() && ( mcu_y + win_h) <= _tft->height())
    {
      _tft->pushImage(mcu_x, mcu_y, win_w, win_h, pImg);
    }

    else if ( ( mcu_y + win_h) >= _tft->height()) JpegDec.abort();

  }

  // calculate how long it took to draw the image
  drawTime = millis() - drawTime; // Calculate the time it took

  // print the results to the serial port
  // Serial.print  ("Total render time was    : "); Serial.print(drawTime); Serial.println(" ms");
  // Serial.println("=====================================");

}

//====================================================================================
//   Print information decoded from the Jpeg image
//====================================================================================
void GfxUi::jpegInfo() {

//  Serial.println("===============");
//  Serial.println("JPEG image info");
//  Serial.println("===============");
//  Serial.print  ("Width      :"); Serial.println(JpegDec.width);
//  Serial.print  ("Height     :"); Serial.println(JpegDec.height);
//  Serial.print  ("Components :"); Serial.println(JpegDec.comps);
//  Serial.print  ("MCU / row  :"); Serial.println(JpegDec.MCUSPerRow);
//  Serial.print  ("MCU / col  :"); Serial.println(JpegDec.MCUSPerCol);
//  Serial.print  ("Scan type  :"); Serial.println(JpegDec.scanType);
//  Serial.print  ("MCU width  :"); Serial.println(JpegDec.MCUWidth);
//  Serial.print  ("MCU height :"); Serial.println(JpegDec.MCUHeight);
//  Serial.println("===============");
//  Serial.println("");

}
//====================================================================================