[FIX] - BmpToPng

Additionally added a line to properly convert from BMP colour variant to the PNG colour variant, previously the image turned blue.

This version now Fixes it for any filtered image.
(Left in the commented out Functionality for them for testing purposes).

- See how to add the library in the wiki!

Author: VerzatileDev

src/assets/images/testpng.png

@@ -96,10 +96,18 @@ int bmp_to_png(const char *input_filename, const char *output_filename)
     // write PNG header info
     png_write_info(png_ptr, info_ptr);
     // write PNG image data
-    for (int y = 0; y < height; y++)
-    {
-        png_bytep row_pointer = &bmp_data[(height - y - 1) * (width * 3 + padding)];
-        png_write_row(png_ptr, row_pointer);
+    for (int y = 0; y < height; y++) {
+    png_bytep row_pointer = &bmp_data[(height - y - 1) * (width * 3 + padding)];
+
+    // Convert BGR to RGB
+    for (int x = 0; x < width; x++) {
+        png_bytep pixel = &row_pointer[x * 3];
+        png_byte temp = pixel[0];
+        pixel[0] = pixel[2];
+        pixel[2] = temp;
+    }
+
+    png_write_row(png_ptr, row_pointer);
     }
     // finish writing PNG file
     png_write_end(png_ptr, NULL);

src/converters/bmp_to_png.c

@@ -1,10 +1,12 @@
 #include "gtk_gui.c"
 //#include "converters/bmp_to_jpeg.c" // Include this line to test the bmp_to_jpeg function
+//#include "converters/bmp_to_png.c"
 
 int main(int argc, char **argv)
 {
     //Include the following line to test the bmp_to_jpeg function
     //bmp_to_jpeg("assets/images/test_image.bmp", "assets/images/testjpg.jpg");
+    //bmp_to_png("assets/images/test_image_negative.bmp", "assets/images/testpng.png");
 
     GtkApplication *app;
     int status;