2.8'' TFT Touch Shield V2 and BMP file direction

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1

In SeeedTFTv2/examples/tftbmp/tftbmp.ino the bmpdraw routine fails to handle BMP images correctly.

Adafruit’s routine had the same problem but they fixed it:

github.com/adafruit/Adafruit-ST … y/issues/6

Add this to ftftbitmap.ino as a global:

uint32_t rowSize;               // Not always = bmpWidth; may have padding

add this at the top of bmpdraw:

  uint32_t pos = 0;

Then here in , this code from Adafruit for reading from the beginning of the row:

 for (i=0; i< bmpHeight; i++) 
 {
+    pos = bmpImageoffset + (bmpHeight - 1 - i) * rowSize;
+    if(f.position() != pos) {
+      f.seek(pos);
+      buffidx = sizeof(sdbuffer);
+    }

    for (j=0; j<bmpWidth; j++) 
    {

Then here in bmpreadheader:

  bmpHeight = read32(f);
+  // BMP rows are padded (if needed) to 4-byte boundary
+ rowSize = (bmpWidth * 3 + 3) & ~3;

The Adafruit version also reads a header to determine whether to flip or not, to handle the rare case of non-flipped BMP files.

2

yeah, we have found this problem , and we would fix it later. Thanks for your attention.