Snapshot with lv_arduino V2.0.3

How-to
8

Ok according your suggestion I changed to :

 if(bSnapshot) { 
          uint32_t data = lv_color_to32(*color_p);
          fsSnapFile.write((const uint8_t *)(&data), sizeof(uint32_t));
      }

but :

C:\ImageMagick\ImageMagick-7.0.8-Q16>magick.exe -size 480x320 -depth 8 rgba:snapshot.bin snap.bmp

give me
image

so I changed the order in command line:

C:\ImageMagick\ImageMagick-7.0.8-Q16>magick.exe -size 480x320 -depth 8 bgra:snapshot.bin snap.bmp

and now I get back the correct colors
image

So to sum up the global solution :

//Global variables
static File fsSnapFile;
static bool bSnapshot;

//Snap function
bool snapshot()
{
  fsSnapFile = SPIFFS.open("/snapshot.bin", "w");
  if (!fsSnapFile) {
    return false;
  }

  bSnapshot = true;
  lv_obj_invalidate(lv_scr_act());
  lv_refr_now(lv_disp_get_default());                    /* Will call our disp_drv.disp_flush function */
  bSnapshot = false;

  fsSnapFile.close();
  return true;
}


/* Display flushing procedure*/
void esp_lv_disp_flush(lv_disp_drv_t *disp, const lv_area_t *area, lv_color_t *color_p)
{
  uint16_t c;
  tft_screen.startWrite(); /* Start new TFT transaction */
  tft_screen.setAddrWindow(area->x1, area->y1, (area->x2 - area->x1 + 1), (area->y2 - area->y1 + 1)); /* set the working window */
  for (int y = area->y1; y <= area->y2; y++) {
    for (int x = area->x1; x <= area->x2; x++) {
      c = color_p->full;
      tft_screen.writeColor(c, 1);
      if(bSnapshot) { 
          uint32_t data = lv_color_to32(*color_p);
          fsSnapFile.write((const uint8_t *)(&data), sizeof(uint32_t));
      }
      color_p++;
    }
  }
  tft.endWrite(); /* terminate TFT transaction */
  lv_disp_flush_ready(disp); /* tell lvgl that flushing is done */
}

then for conversion (magick.exe is the Windows equivalent in ImageMagick for convert due to some name conflict)

C:\ImageMagick\ImageMagick-7.0.8-Q16>magick.exe -size 480x320 -depth 8 bgra:snapshot.bin snap.bmp

Thank you for your advices :smiley_cat: