Hello.
If I ask you some help, it is because a whole day of research wasn't enough to solve my problem.
I'm trying to draw a bitmap on my display (reference here) with my teensy 4.0 (same thing). I got an exemple script on the internet with the famous void bmpDraw(char *filename, uint8_t x, uint16_t y), but what my display print isn't what it is supposed to print, and I did not see anywhere on the internet someone with the same problem.
Here is the function :
#define BUFFPIXEL 20
void bmpDraw(char *filename, uint8_t x, uint16_t y) {
File bmpFile;
int bmpWidth, bmpHeight; // W+H in pixels
uint8_t bmpDepth; // Bit depth (currently must be 24)
uint32_t bmpImageoffset; // Start of image data in file
uint32_t rowSize; // Not always = bmpWidth; may have padding
uint8_t sdbuffer[3*BUFFPIXEL]; // pixel buffer (R+G+B per pixel)
uint8_t buffidx = sizeof(sdbuffer); // Current position in sdbuffer
boolean goodBmp = false; // Set to true on valid header parse
boolean flip = true; // BMP is stored bottom-to-top
int w, h, row, col;
uint8_t r, g, b;
uint32_t pos = 0, startTime = millis();
if((x >= tft.width()) || (y >= tft.height())) return;
Serial.println();
Serial.print(F("Loading image '"));
Serial.print(filename);
Serial.println(''');
// Open requested file on SD card
if ((bmpFile = SD.open(filename)) == 0) {
Serial.print(F("File not found"));
return;
}
// Parse BMP header
if(read16(bmpFile) == 0x4D42) { // BMP signature
Serial.print(F("File size: ")); Serial.println(read32(bmpFile));
(void)read32(bmpFile); // Read & ignore creator bytes
bmpImageoffset = read32(bmpFile); // Start of image data
Serial.print(F("Image Offset: ")); Serial.println(bmpImageoffset, DEC);
// Read DIB header
Serial.print(F("Header size: ")); Serial.println(read32(bmpFile));
bmpWidth = read32(bmpFile);
bmpHeight = read32(bmpFile);
if(read16(bmpFile) == 1) { // # planes -- must be '1'
bmpDepth = read16(bmpFile); // bits per pixel
Serial.print(F("Bit Depth: ")); Serial.println(bmpDepth);
if((bmpDepth == 24) && (read32(bmpFile) == 0)) { // 0 = uncompressed
goodBmp = true; // Supported BMP format -- proceed!
Serial.print(F("Image size: "));
Serial.print(bmpWidth);
Serial.print('x');
Serial.println(bmpHeight);
// BMP rows are padded (if needed) to 4-byte boundary
rowSize = (bmpWidth * 3 + 3) & ~3;
// If bmpHeight is negative, image is in top-down order.
// This is not canon but has been observed in the wild.
if(bmpHeight < 0) {
bmpHeight = -bmpHeight;
flip = false;
}
// Crop area to be loaded
w = bmpWidth;
h = bmpHeight;
if((x+w-1) >= tft.width()) w = tft.width() - x;
if((y+h-1) >= tft.height()) h = tft.height() - y;
// Set TFT address window to clipped image bounds
tft.startWrite();
tft.setAddrWindow(x, y, w, h);
for (row=0; row<h; row++) { // For each scanline...
// Seek to start of scan line. It might seem labor-
// intensive to be doing this on every line, but this
// method covers a lot of gritty details like cropping
// and scanline padding. Also, the seek only takes
// place if the file position actually needs to change
// (avoids a lot of cluster math in SD library).
if(flip) // Bitmap is stored bottom-to-top order (normal BMP)
pos = bmpImageoffset + (bmpHeight - 1 - row) * rowSize;
else // Bitmap is stored top-to-bottom
pos = bmpImageoffset + row * rowSize;
if(bmpFile.position() != pos) { // Need seek?
tft.endWrite();
bmpFile.seek(pos);
buffidx = sizeof(sdbuffer); // Force buffer reload
}
for (col=0; col<w; col++) { // For each pixel...
// Time to read more pixel data?
if (buffidx >= sizeof(sdbuffer)) { // Indeed
bmpFile.read(sdbuffer, sizeof(sdbuffer));
buffidx = 0; // Set index to beginning
tft.startWrite();
}
// Convert pixel from BMP to TFT format, push to display
b = sdbuffer[buffidx++];
g = sdbuffer[buffidx++];
r = sdbuffer[buffidx++];
tft.pushColor(tft.color565(r,g,b));
} // end pixel
} // end scanline
tft.endWrite();
Serial.print(F("Loaded in "));
Serial.print(millis() - startTime);
Serial.println(" ms");
} // end goodBmp
}
}
bmpFile.close();
if(!goodBmp) Serial.println(F("BMP format not recognized."));
}
I hope you'll be able to help me, thanks alot.
Quentin
