Update kernel with graphics and font support

nel_os_kernel/Cargo.lock

@@ -2,6 +2,26 @@
 # It is not intended for manual editing.
 version = 4
 
+[[package]]
+name = "ab_glyph"
+version = "0.2.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e0f4f6fbdc5ee39f2ede9f5f3ec79477271a6d6a2baff22310d51736bda6cea"
+dependencies = [
+ "ab_glyph_rasterizer",
+ "libm",
+ "owned_ttf_parser",
+]
+
+[[package]]
+name = "ab_glyph_rasterizer"
+version = "0.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2187590a23ab1e3df8681afdf0987c48504d80291f002fcdb651f0ef5e25169"
+dependencies = [
+ "libm",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.5.0"
@@ -26,6 +46,15 @@ version = "2.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1b8e56985ec62d17e9c1001dc89c88ecd7dc08e47eba5ec7c29c7b5eeecde967"
 
+[[package]]
+name = "core_maths"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77745e017f5edba1a9c1d854f6f3a52dac8a12dd5af5d2f54aecf61e43d80d30"
+dependencies = [
+ "libm",
+]
+
 [[package]]
 name = "lazy_static"
 version = "1.5.0"
@@ -35,6 +64,12 @@ dependencies = [
  "spin 0.9.8",
 ]
 
+[[package]]
+name = "libm"
+version = "0.2.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f9fbbcab51052fe104eb5e5d351cf728d30a5be1fe14d9be8a3b097481fb97de"
+
 [[package]]
 name = "linked_list_allocator"
 version = "0.9.1"
@@ -62,6 +97,7 @@ version = "0.1.0"
 name = "nel_os_kernel"
 version = "0.1.0"
 dependencies = [
+ "ab_glyph",
  "lazy_static",
  "linked_list_allocator",
  "nel_os_common",
@@ -70,6 +106,15 @@ dependencies = [
  "x86_64",
 ]
 
+[[package]]
+name = "owned_ttf_parser"
+version = "0.25.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "22ec719bbf3b2a81c109a4e20b1f129b5566b7dce654bc3872f6a05abf82b2c4"
+dependencies = [
+ "ttf-parser",
+]
+
 [[package]]
 name = "raw-cpuid"
 version = "10.7.0"
@@ -115,6 +160,15 @@ dependencies = [
  "lock_api",
 ]
 
+[[package]]
+name = "ttf-parser"
+version = "0.25.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2df906b07856748fa3f6e0ad0cbaa047052d4a7dd609e231c4f72cee8c36f31"
+dependencies = [
+ "core_maths",
+]
+
 [[package]]
 name = "uart_16550"
 version = "0.3.2"

nel_os_kernel/Cargo.toml

@@ -10,3 +10,4 @@ uart_16550 = "0.3.2"
 x86_64 = "0.15.2"
 nel_os_common = { path = "../nel_os_common" }
 linked_list_allocator = "0.9.1"
+ab_glyph = { version = "0.2", features = ["libm"], default-features = false }

nel_os_kernel/src/graphics.rs

@@ -0,0 +1,133 @@
+use ab_glyph::{Font, FontRef, ScaleFont};
+use lazy_static::lazy_static;
+use nel_os_common::gop::{FrameBuffer as RawFrameBuffer, PixelFormat as RawPixelFormat};
+use spin::Mutex;
+
+static FONT: &[u8] = include_bytes!("../Tamzen7x14r.ttf");
+
+lazy_static! {
+    pub static ref FRAME_BUFFER: Mutex<Option<FrameBuffer>> = Mutex::new(None);
+}
+
+pub enum PixelFormat {
+    Rgb,
+    Bgr,
+}
+
+pub struct FrameBuffer {
+    pub frame_buffer: *mut u8,
+    pub width: usize,
+    pub height: usize,
+    pub stride: usize,
+
+    pub pixel_format: PixelFormat,
+
+    pub text_cursor: (usize, usize),
+}
+
+unsafe impl Send for FrameBuffer {}
+unsafe impl Sync for FrameBuffer {}
+
+impl FrameBuffer {
+    pub fn from_raw_buffer(raw_buffer: &RawFrameBuffer) -> Self {
+        Self {
+            frame_buffer: raw_buffer.frame_buffer,
+            width: raw_buffer.width,
+            height: raw_buffer.height,
+
+            stride: raw_buffer.stride,
+            pixel_format: match raw_buffer.pixl_format {
+                RawPixelFormat::Rgb => PixelFormat::Rgb,
+                RawPixelFormat::Bgr => PixelFormat::Bgr,
+            },
+            text_cursor: (0, 0),
+        }
+    }
+
+    pub fn pixel_index(&self, x: usize, y: usize) -> Option<usize> {
+        if x < self.width && y < self.height {
+            Some((y * self.stride + x) * 4)
+        } else {
+            None
+        }
+    }
+
+    pub fn draw_pixel(&self, r: u8, g: u8, b: u8, x: usize, y: usize) {
+        if x >= self.width || y >= self.height {
+            return;
+        }
+
+        let pixel_index = self.pixel_index(x, y).unwrap();
+        unsafe {
+            let pixel_ptr = self.frame_buffer.add(pixel_index);
+            match self.pixel_format {
+                PixelFormat::Rgb => {
+                    *pixel_ptr.add(0) = r;
+                    *pixel_ptr.add(1) = g;
+                    *pixel_ptr.add(2) = b;
+                }
+
+                PixelFormat::Bgr => {
+                    *pixel_ptr.add(0) = b;
+                    *pixel_ptr.add(1) = g;
+                    *pixel_ptr.add(2) = r;
+                }
+            }
+        }
+    }
+
+    pub fn print_text(&mut self, text: &str) {
+        let (mut x, mut y) = self.text_cursor;
+
+        for c in text.chars() {
+            if c == '\n' {
+                x = 0;
+                y += 14;
+
+                continue;
+            }
+
+            self.draw_char(c, x, y);
+            x += 8;
+            if x + 8 > self.width {
+                x = 0;
+                y += 14;
+            }
+        }
+
+        self.text_cursor = (x, y);
+    }
+
+    pub fn print_char(&mut self, c: char) {
+        let (x, y) = self.text_cursor;
+
+        self.draw_char(c, x, y);
+        self.text_cursor.0 += 8;
+        if self.text_cursor.0 >= self.width {
+            self.text_cursor.0 = 0;
+            self.text_cursor.1 += 14;
+        }
+    }
+
+    pub fn draw_char(&self, c: char, x: usize, y: usize) {
+        let font = FontRef::try_from_slice(FONT).unwrap();
+
+        let font = font.as_scaled(14.0);
+
+        let mut glyph = font.scaled_glyph(c);
+        glyph.position = ab_glyph::point(0.0, font.ascent());
+        if let Some(glyph) = font.outline_glyph(glyph) {
+            let min_x = glyph.px_bounds().min.x as usize;
+
+            let min_y = glyph.px_bounds().min.y as usize;
+
+            glyph.draw(|fx, fy, c| {
+                let pixel_x = fx + min_x as u32 + x as u32;
+                let pixel_y = fy + min_y as u32 + y as u32;
+                let color = if c > 0.0 { (c * 255.0) as u8 } else { 64 };
+
+                self.draw_pixel(color, color, color, pixel_x as usize, pixel_y as usize);
+            });
+        }
+    }
+}

nel_os_kernel/src/main.rs

@@ -5,6 +5,7 @@ extern crate alloc;
 
 pub mod allocator;
 pub mod constant;
+pub mod graphics;
 pub mod logging;
 pub mod memory;
 pub mod paging;
@@ -20,6 +21,7 @@ use x86_64::{structures::paging::OffsetPageTable, VirtAddr};
 
 use crate::{
     constant::{BANNER, KERNEL_STACK_SIZE, PKG_VERSION},
+    graphics::{FrameBuffer, FRAME_BUFFER},
     memory::BitmapMemoryTable,
 };
 
@@ -67,8 +69,6 @@ fn hlt_loop() -> ! {
 
 #[unsafe(no_mangle)]
 pub extern "sysv64" fn main(boot_info: &nel_os_common::BootInfo) {
-    println!("{} v{}", BANNER, PKG_VERSION);
-
     let virt = VirtAddr::new(
         x86_64::registers::control::Cr3::read()
             .0
@@ -110,9 +110,22 @@ pub extern "sysv64" fn main(boot_info: &nel_os_common::BootInfo) {
 
     allocator::init_heap(&mut mapper, &mut bitmap_table).unwrap();
 
-    let mut test_vec = vec![1, 2, 3, 4, 9];
-    test_vec.push(10);
-    info!("Vector test: {:?}", test_vec);
+    let frame_buffer = FrameBuffer::from_raw_buffer(&boot_info.frame_buffer);
+
+    for x in 0..frame_buffer.width {
+        for y in 0..frame_buffer.height {
+            frame_buffer.draw_pixel(64, 64, 64, x, y);
+        }
+    }
+
+    FRAME_BUFFER.lock().replace(frame_buffer);
+
+    println!("{} v{}", BANNER, PKG_VERSION);
+    info!(
+        "Usable memory: {}MiB ({:.1}GiB)",
+        usable_frame * 4 / 1024,
+        usable_frame as f64 * 4. / 1024. / 1024.
+    );
 
     hlt_loop();
 }

nel_os_kernel/src/serial.rs

@@ -1,7 +1,10 @@
+use alloc::format;
 use lazy_static::lazy_static;
 use spin::Mutex;
 use uart_16550::SerialPort;
 
+use crate::graphics::FRAME_BUFFER;
+
 lazy_static! {
     pub static ref SERIAL1: Mutex<SerialPort> = {
         let mut serial_port = unsafe { SerialPort::new(0x3F8) };
@@ -19,6 +22,13 @@ pub fn _print(args: ::core::fmt::Arguments) {
             .lock()
             .write_fmt(args)
             .expect("Printing to serial failed");
+
+        let mut fb = FRAME_BUFFER.lock();
+        let fb = fb.as_mut();
+
+        if let Some(frame_buffer) = fb {
+            frame_buffer.print_text(format!("{args}").as_str());
+        }
     });
 }