feat: Added bitmap writing

1 files changed, 107 insertions, 0 deletions

diff --git a/src/bmp.rs b/src/bmp.rs
new file mode 100644
index 0000000..f6c0c7e
--- /dev/null
+++ b/src/bmp.rs
@@ -0,0 +1,107 @@
+use crate::{image::{ColorType, Image, ImageBase, PixelArr, RGB}, reader::FileReader, writer::FileWriter};
+
+impl Image for BMPImage
+{
+	fn read_image(reader: &mut FileReader) -> Result<ImageBase, &'static str>
+	{
+		let magic: [u8; 2] = reader.read_array();
+		if magic != [0x42, 0x4d]
+		{
+			return Err("Not a bitmap!");
+		}
+		
+		let _file_size: u32 = reader.read();
+		reader.skip(4);
+		let _offset: u32 = reader.read();
+		
+		let header_size: u32 = reader.read();
+
+		// println!("File header: {file_size} {offset} {header_size}");
+
+		if header_size == 40
+		{
+
+			let width: u32 = reader.read();
+			let height: u32 = reader.read();
+			let _color_planes: u16 = reader.read();
+			let bpp = reader.read::<2, u16>() as u8;
+			let compression_method: u32 = reader.read();
+			let _image_size: u32 = reader.read();
+			let _horr_res: u32 = reader.read();
+			let _vert_res: u32 = reader.read();
+			let _color_count: u32 = reader.read();
+			let _impotant_color_count: u32 = reader.read();
+
+			if
+				bpp != 24
+				|| compression_method != 0
+			{
+				return Err("bpp or compresssion method not supported")
+			}
+
+			let row_size = (((bpp as u32) * width + 31)/32) * 4;
+			let skip: usize = (row_size - width * 3) as usize;
+			let mut pixel_arr = PixelArr::new(width, height);
+			for y in (0..height).rev()
+			{
+				for x in 0..width
+				{
+					let mut pixel = RGB::DEFAULT;
+					pixel.b = reader.read();
+					pixel.g = reader.read();
+					pixel.r = reader.read();
+					pixel_arr[(x as usize, y as usize)] = pixel;
+				}
+				reader.skip(skip);
+			}
+
+			return Ok(ImageBase
+					  {
+						  bit_depth: bpp,
+						  pixels: pixel_arr,
+					  })
+		}
+		else
+		{
+			return Err("Header size not supported yet");
+		}
+		
+		
+	}
+
+	fn write_image(image: &ImageBase, writer: &mut FileWriter) -> () {
+		writer.write_array([0x42, 0x4d] as [u8; 2]);
+
+		let row_size = (((24) * image.pixels.width + 31)/32) * 4;
+		let file_size: u32 = 14 + 12 + row_size*image.pixels.height;
+		let offset: u32 = 26;
+		writer.write(file_size as u32);
+		writer.write_zeros(4);
+		writer.write(offset as u32);
+		writer.write(12 as u32); // Header size
+
+		writer.write(image.pixels.width as u16);
+		writer.write(image.pixels.height as u16);
+		writer.write(1 as u16); // Color planes
+		writer.write(24 as u16); // bpp
+
+		let skip: usize = (row_size - image.pixels.width * 3) as usize;
+		for y in (0..image.pixels.height).rev()
+		{
+			for x in 0..image.pixels.width
+			{
+				let pixel = image.pixels[(x as usize, y as usize)];
+				writer.write(pixel.b);
+				writer.write(pixel.g);
+				writer.write(pixel.r);
+			}
+			writer.write_zeros(skip);
+		}
+		writer.flush();
+	}
+}
+
+
+pub struct BMPImage
+{
+}