Simple mandelbrot in rust

bench/link.ld

@@ -34,6 +34,4 @@ SECTIONS
     PROVIDE(_stack_size = 1024); /* 1 KiB */
     PROVIDE(_stack_start = _memory_end);
     PROVIDE(_stack_end = _stack_start - _stack_size);
-
-
 }

bench/programs_rust/.cargo/config.toml

@@ -14,3 +14,4 @@ rustflags = [
 
 [unstable]
 build-std = ["core", "compiler_builtins"]
+build-std-features = ["compiler-builtins-mem"]

bench/programs_rust/hello-rust/Cargo.toml

@@ -5,3 +5,4 @@ edition = "2024"
 
 [dependencies]
 fpga-lib = { path = "../fpga-lib" }
+libm = "0.2.11"

bench/programs_rust/hello-rust/src/main.rs

@@ -1,51 +1,120 @@
 #![no_std]
 #![no_main]
 
-use core::arch::asm;
+use core::{
+    arch::asm,
+    ops::{Add, Mul},
+};
 
 use fpga_lib::{
     interface::{Buttons, Leds},
     panic_handler,
     register::X31,
-    vga::{BLACK, BLUE, FONT_WIDTH, GREEN, RED, VGA, WHITE},
+    vga::{BLACK, BLUE, Color, FONT_WIDTH, GREEN, HEIGHT, RED, VGA, WHITE, WIDTH},
 };
 
+type Float = f32;
+pub const ITERATIONS: usize = 100;
+pub const ASPECT_RATIO: f32 = WIDTH as f32 / HEIGHT as f32;
+
+#[derive(Clone, Copy)]
+struct Complex(Float, Float);
+
+impl Complex
+{
+    pub fn sq_mag(&self) -> Float
+    {
+        self.0 * self.0 + self.1 * self.1
+    }
+}
+
+pub fn map(x: Float, xmin: Float, xmax: Float, ymin: Float, ymax: Float) -> Float
+{
+    ((x - xmin) / (xmax - xmin)) * (ymax - ymin) + ymin
+}
+
+impl Add for Complex
+{
+    type Output = Complex;
+
+    fn add(self, Self(a, b): Self) -> Self::Output
+    {
+        Complex(self.0 + a, self.1 + b)
+    }
+}
+
+impl Mul for Complex
+{
+    type Output = Complex;
+
+    fn mul(self, Self(a, b): Self) -> Self::Output
+    {
+        Complex(self.0 * a - self.1 * b, self.0 * b + self.1 * a)
+    }
+}
+
 panic_handler! {}
 
 #[unsafe(no_mangle)]
 pub extern "C" fn main() -> !
 {
-    loop
+    let color_lut: [Color; ITERATIONS] = {
+        let mut tab = [BLACK; _];
+        for i in 0..(ITERATIONS - 1)
+        {
+            let val = ((i as Float / ITERATIONS as Float) * 255.) as u8;
+            tab[i] = Color::from_rgb(val, val, val);
+        }
+
+        tab
+    };
+
+    let width = 2.;
+    for x in 0..WIDTH
     {
-        unsafe {
-            VGA::draw_string(10, 10, "Running RUST !", GREEN);
-            VGA::draw_string(10, 23, "LedIp state :", RED);
+        for y in 0..HEIGHT
+        {
+            let pos = Complex(
+                map(
+                    x as Float,
+                    0.,
+                    WIDTH as Float,
+                    -width * ASPECT_RATIO * 0.5,
+                    width * ASPECT_RATIO * 0.5,
+                ) - 0.5,
+                map(y as Float, 0., HEIGHT as Float, -width * 0.5, width * 0.5),
+            );
+            let mut acc = pos;
+            let mut iter = 0;
 
-            let clint_time: *mut u64 = 0x0200bff8 as *mut u64;
-
-            let clocks = *clint_time;
-            let seconds = clocks / 80_000_000;
-            VGA::draw_string(100, 10, "CLint:", BLUE);
-            VGA::draw_u64(150, 10, clocks, BLUE, BLACK);
-            VGA::draw_string(100, 23, "(s)", BLUE);
-            VGA::draw_u64(150, 23, seconds, BLUE, BLACK);
-
-            for i in 0..4
+            // Optimisations
+            let p = ((pos.0 - 0.25) * (pos.0 - 0.25)) + pos.1 * pos.1;
+            if (pos.0 < libm::sqrtf(p) - 2. * p + 0.25)
+                || (pos.0 + 1.) * (pos.0 + 1.) + pos.1 * pos.1 < 1. / 16.
             {
-                VGA::draw_char(10 + i * 16, 46, 'B', RED);
-                VGA::draw_char(16 + i * 16, 46, (b'0' + i as u8) as char, RED);
+                iter = ITERATIONS - 1;
+            }
+            else
+            {
+                for i in 0..ITERATIONS
+                {
+                    acc = acc * acc + pos;
+                    if acc.sq_mag() > 1.
+                    {
+                        iter = i;
+                        break;
+                    }
+                }
+            }
 
-                if Buttons::get_button(i as u8)
-                {
-                    Leds::set_led(i as u8, true);
-                    VGA::draw_char_bg(10 + i * 16, 59, '1', GREEN, BLACK);
-                }
-                else
-                {
-                    Leds::set_led(i as u8, false);
-                    VGA::draw_char_bg(10 + i * 16, 59, '0', RED, BLACK);
-                }
+            unsafe {
+                VGA::write_pixel_unsafe(x as u16, y as u16, color_lut[iter]);
             }
         }
     }
+
+    loop
+    {
+        core::hint::spin_loop();
+    }
 }