Starts adding fontplate for VGA

bench/programs_rust/fpga-lib/src/vga.rs

@@ -0,0 +1,48 @@
+use fpga_lib_macros::include_font_plate;
+
+pub const VGA_ADDRESS: *mut Color = 0x80000000 as *mut Color;
+pub const WIDTH: usize = 320;
+pub const HEIGHT: usize = 240;
+
+#[repr(transparent)]
+pub struct Color(pub(crate) u8);
+
+impl Color {
+    pub const fn from_rgb(r: u8, g: u8, b: u8) -> Self {
+        Self(((r >> 6) << 6) | ((g >> 5) << 3) | (b >> 5))
+    }
+}
+
+pub const WHITE: Color = Color::from_rgb(255, 255, 255);
+pub const GRAY: Color = Color::from_rgb(128, 128, 128);
+pub const LIGHT_GRAY: Color = Color::from_rgb(128, 64, 64);
+pub const BLACK: Color = Color::from_rgb(0, 0, 0);
+pub const RED: Color = Color::from_rgb(255, 0, 0);
+pub const GREEN: Color = Color::from_rgb(0, 255, 0);
+pub const BLUE: Color = Color::from_rgb(0, 0, 255);
+
+pub struct VGA {}
+
+impl VGA {
+    /// # Safety
+    /// `x` must be less than `WIDTH` and `y` must be less than `HEIGHT`
+    pub unsafe fn write_pixel_unsafe(x: u16, y: u16, color: Color) {
+        unsafe { *VGA_ADDRESS.add(x as usize + y as usize * WIDTH) = color }
+    }
+
+    pub unsafe fn draw_char(x: u16, y: u16, c: char) {
+        let c = c as u8 - b' ';
+        for i in 0..FONT_HEIGHT {
+            for j in 0..FONT_WIDTH {
+                
+            }
+        }
+    }
+}
+
+pub const FONT_WIDTH: usize = 6;
+pub const FONT_HEIGHT: usize = 13;
+pub const FONTPLATE_WIDTH: usize = 32 * FONT_WIDTH;
+pub const FONTPLATE_HEIGHT: usize = 3 * FONT_HEIGHT;
+pub const FONTPLATE_SIZE: usize = FONTPLATE_WIDTH * FONTPLATE_HEIGHT / 8;
+pub const FONTPLATE: [u8; FONTPLATE_SIZE] = include_font_plate! {"fontplate.png"};