diff --git a/mas/fractals/mandel/src/main.rs b/mas/fractals/mandel/src/main.rs
index 3f6d74b..14eb5f0 100644
--- a/mas/fractals/mandel/src/main.rs
+++ b/mas/fractals/mandel/src/main.rs
@@ -77,18 +77,28 @@ fn main() {
                     zy *= zoom_out;
                     zx *= zoom_out;
                 },
+                Event::KeyDown { keycode: Some(Keycode::W), .. } => {
+                    println!("(+) DEPTH= {depth}");
+                    render_new = true;
+                    depth *= 2;
+                },
+                Event::KeyDown { keycode: Some(Keycode::S), .. } => {
+                    println!("(-) DEPTH= {depth}");
+                    render_new = true;
+                    depth /= 2;
+                },
                 _ => {}
             }
         }
 
         if render_new {
-            let mut maps = &mut Vec::new();
+            let maps = &mut Vec::new();
             for thread_id in 0..threads {
-                thread::spawn(|| { // do cool threads for performance
-                    let mut pixmap = render::prerender_mandelbrot(
-                        width, height, depth, 
-                        zx, zy, dx, dy, 
-                        thread_id, threads, w_sector_size, h_sector_size);
+                thread::spawn(|| { 
+                    let pixmap = render::prerender_mandelbrot(
+                        &width, &height, &depth, 
+                        &zx, &zy, &dx, &dy, 
+                        &thread_id, &threads, &w_sector_size, &h_sector_size);
                     maps.push(pixmap);
                 });
             }
diff --git a/mas/fractals/mandel/src/render.rs b/mas/fractals/mandel/src/render.rs
index 11c66f0..8cb6a10 100644
--- a/mas/fractals/mandel/src/render.rs
+++ b/mas/fractals/mandel/src/render.rs
@@ -66,10 +66,10 @@ pub fn set_pixel(canvas: &mut Canvas<sdl2::video::Window>, x: i32, y: i32, color
     canvas.fill_rect(Rect::new(x, y, 1, 1));
 }
 
-pub fn prerender_mandelbrot(w: u32, h: u32, depth: u32, xzoom: f32, yzoom: f32, xoffset: f32, yoffset: f32, thread_id: u32, threads: u32, w_sector_size: u32, h_sector_size: u32) -> PixelMap {
+pub fn prerender_mandelbrot(w: &u32, h: &u32, depth: &u32, xzoom: &f32, yzoom: &f32, xoffset: &f32, yoffset: &f32, thread_id: &u32, threads: &u32, w_sector_size: &u32, h_sector_size: &u32) -> PixelMap {
     println!("Rendering...");
-    let mut pixmap = PixelMap::new(w, h, thread_id * w_sector_size, thread_id * h_sector_size);
-    mandelbrot(&mut pixmap, w, h, depth, xzoom, yzoom, xoffset, yoffset);
+    let mut pixmap = PixelMap::new(*w, *h, thread_id * w_sector_size, thread_id * h_sector_size);
+    mandelbrot(&mut pixmap, *w, *h, *depth, *xzoom, *yzoom, *xoffset, *yoffset);
     println!("Post mandel render");
 
     return pixmap;