a

src/pix/canvas.rs

@@ -50,16 +50,42 @@ impl Canvas {
 
     /// Spawn the painters for this canvas
     fn spawn_painters(&mut self, binary: bool, flush: bool) {
-        // Spawn some painters
-        for i in 0..self.painter_count {
-            // Determine the slice width
-            let width = self.size.0 / (self.painter_count as u16);
+        let grid = (self.painter_count as f64).sqrt() as usize;
+        if grid * grid == self.painter_count {
+            let tile_w = self.size.0 / (grid as u16);
+            let tile_h = self.size.1 / (grid as u16);
 
-            // Define the area to paint per thread
-            let painter_area = Rect::from((i as u16) * width, 0, width, self.size.1);
+            for row in 0..grid {
+                for col in 0..grid {
+                    let x = (col as u16) * tile_w;
+                    let y = (row as u16) * tile_h;
+                    let w = if col == grid - 1 {
+                        self.size.0 - x
+                    } else {
+                        tile_w
+                    };
+                    let h = if row == grid - 1 {
+                        self.size.1 - y
+                    } else {
+                        tile_h
+                    };
 
-            // Spawn the painter
-            self.spawn_painter(painter_area, binary, flush);
+                    let painter_area = Rect::from(x, y, w, h);
+                    self.spawn_painter(painter_area, binary, flush);
+                }
+            }
+        } else {
+            // Spawn some painters
+            for i in 0..self.painter_count {
+                // Determine the slice width
+                let width = self.size.0 / (self.painter_count as u16);
+
+                // Define the area to paint per thread
+                let painter_area = Rect::from((i as u16) * width, 0, width, self.size.1);
+
+                // Spawn the painter
+                self.spawn_painter(painter_area, binary, flush);
+            }
         }
     }