diff --git a/challenges/coding-in-the-cabana/005_marching_squares/P5_metaballs_interpolation/sketch.js b/challenges/coding-in-the-cabana/005_marching_squares/P5_metaballs_interpolation/sketch.js
index 8aab592a0f..a131b01c9f 100644
--- a/challenges/coding-in-the-cabana/005_marching_squares/P5_metaballs_interpolation/sketch.js
+++ b/challenges/coding-in-the-cabana/005_marching_squares/P5_metaballs_interpolation/sketch.js
@@ -1,160 +1,160 @@
-// Marching Squares Metaballs Interpolation
-// Coding in the Cabana
-// The Coding Train / Daniel Shiffman
-// https://thecodingtrain.com/challenges/coding-in-the-cabana/005-marching-squares.html
-// https://youtu.be/0ZONMNUKTfU
-// p5 port: https://editor.p5js.org/codingtrain/sketches/hEB4588QC
-
-let bubbles = [];
-let field = [];
-let rez = 16;
-let cols, rows;
-
-function setup() {
-  createCanvas(400, 300);
-  cols = 1 + width / rez;
-  rows = 1 + height / rez;
-  for (let i = 0; i < cols; i++) {
-    let k = [];
-    for (let j = 0; j < rows; j++) {
-      k.push(0);
-    }
-    field.push(k);
-  }
-  for (let i = 0; i < 3; i++) {
-    bubbles.push(new Bubble());
-  }
-}
-
-function drawLine(v1, v2) {
-  line(v1.x, v1.y, v2.x, v2.y);
-}
-
-function draw() {
-  background(0);
-
-  for (let i = 0; i < cols; i++) {
-    for (let j = 0; j < rows; j++) {
-      let sum = 0;
-      let x = i * rez;
-      let y = j * rez;
-      for (let b of bubbles) {
-        sum += (b.r * b.r) / ((x - b.x) * (x - b.x) + (y - b.y) * (y - b.y));
-      }
-      field[i][j] = sum;
-    }
-  }
-  //for (int i = 0; i < cols; i++) {
-  //  for (int j = 0; j < rows; j++) {
-  //    fill(field[i][j]*255);
-  //    noStroke();
-  //    rect(i*rez, j*rez, rez, rez);
-  //  }
-  //}
-
-  for (let b of bubbles) {
-    b.update();
-    b.show();
-  }
-
-  for (let i = 0; i < cols - 1; i++) {
-    for (let j = 0; j < rows - 1; j++) {
-      let x = i * rez;
-      let y = j * rez;
-
-      // interpolation
-      let threshold = 1;
-      let c1 = field[i][j] < threshold ? 0 : 1;
-      let c2 = field[i + 1][j] < threshold ? 0 : 1;
-      let c3 = field[i + 1][j + 1] < threshold ? 0 : 1;
-      let c4 = field[i][j + 1] < threshold ? 0 : 1;
-      let state = getState(c1, c2, c3, c4);
-      stroke(255);
-      strokeWeight(2);
-      let a_val = field[i][j];
-      let b_val = field[i + 1][j];
-      let c_val = field[i + 1][j + 1];
-      let d_val = field[i][j + 1];
-
-      let a = createVector();
-      let amt = (1 - a_val) / (b_val - a_val);
-      a.x = lerp(x, x + rez, amt);
-      a.y = y;
-
-      let b = createVector();
-      amt = (1 - b_val) / (c_val - b_val);
-      b.x = x + rez;
-      b.y = lerp(y, y + rez, amt);
-
-      let c = createVector();
-      amt = (1 - d_val) / (c_val - d_val);
-      c.x = lerp(x, x + rez, amt);
-      c.y = y + rez;
-      for (let i = 0; i < cols; i++) {
-        let k = [];
-        for (let j = 0; j < rows; j++) {
-          k.push(0);
-        }
-        field.push(k);
-      }
-
-      let d = createVector();
-      amt = (1 - a_val) / (d_val - a_val);
-      d.x = x;
-      d.y = lerp(y, y + rez, amt);
-
-      stroke(255);
-      strokeWeight(2);
-      switch (state) {
-        case 1:
-          drawLine(c, d);
-          break;
-        case 2:
-          drawLine(b, c);
-          break;
-        case 3:
-          drawLine(b, d);
-          break;
-        case 4:
-          drawLine(a, b);
-          break;
-        case 5:
-          drawLine(a, d);
-          drawLine(b, c);
-          break;
-        case 6:
-          drawLine(a, c);
-          break;
-        case 7:
-          drawLine(a, d);
-          break;
-        case 8:
-          drawLine(a, d);
-          break;
-        case 9:
-          drawLine(a, c);
-          break;
-        case 10:
-          drawLine(a, b);
-          drawLine(c, d);
-          break;
-        case 11:
-          drawLine(a, b);
-          break;
-        case 12:
-          drawLine(b, d);
-          break;
-        case 13:
-          drawLine(b, c);
-          break;
-        case 14:
-          drawLine(c, d);
-          break;
-      }
-    }
-  }
-}
-
-function getState(a, b, c, d) {
-  return a * 8 + b * 4 + c * 2 + d * 1;
-}
+// Marching Squares Metaballs Interpolation
+// Coding in the Cabana
+// The Coding Train / Daniel Shiffman
+// https://thecodingtrain.com/challenges/coding-in-the-cabana/005-marching-squares.html
+// https://youtu.be/0ZONMNUKTfU
+// p5 port: https://editor.p5js.org/codingtrain/sketches/hEB4588QC
+
+let bubbles = [];
+let field = [];
+let rez = 16;
+let cols, rows;
+
+function setup() {
+  createCanvas(400, 300);
+  cols = 1 + width / rez;
+  rows = 1 + height / rez;
+  for (let i = 0; i < cols; i++) {
+    let k = [];
+    for (let j = 0; j < rows; j++) {
+      k.push(0);
+    }
+    field.push(k);
+  }
+  for (let i = 0; i < 3; i++) {
+    bubbles.push(new Bubble());
+  }
+}
+
+function drawLine(v1, v2) {
+  line(v1.x, v1.y, v2.x, v2.y);
+}
+
+function draw() {
+  background(0);
+
+  for (let i = 0; i < cols; i++) {
+    for (let j = 0; j < rows; j++) {
+      let sum = 0;
+      let x = i * rez;
+      let y = j * rez;
+      for (let b of bubbles) {
+        sum += (b.r * b.r) / ((x - b.x) * (x - b.x) + (y - b.y) * (y - b.y));
+      }
+      field[i][j] = sum;
+    }
+  }
+  //for (int i = 0; i < cols; i++) {
+  //  for (int j = 0; j < rows; j++) {
+  //    fill(field[i][j]*255);
+  //    noStroke();
+  //    rect(i*rez, j*rez, rez, rez);
+  //  }
+  //}
+
+  for (let b of bubbles) {
+    b.update();
+    b.show();
+  }
+
+  for (let i = 0; i < cols - 1; i++) {
+    for (let j = 0; j < rows - 1; j++) {
+      let x = i * rez;
+      let y = j * rez;
+
+      // interpolation
+      let threshold = 1;
+      let c1 = field[i][j] < threshold ? 0 : 1;
+      let c2 = field[i + 1][j] < threshold ? 0 : 1;
+      let c3 = field[i + 1][j + 1] < threshold ? 0 : 1;
+      let c4 = field[i][j + 1] < threshold ? 0 : 1;
+      let state = getState(c1, c2, c3, c4);
+      stroke(255);
+      strokeWeight(2);
+      let a_val = field[i][j];
+      let b_val = field[i + 1][j];
+      let c_val = field[i + 1][j + 1];
+      let d_val = field[i][j + 1];
+
+      let a = createVector();
+      let amt = (1 - a_val) / (b_val - a_val);
+      a.x = lerp(x, x + rez, amt);
+      a.y = y;
+
+      let b = createVector();
+      amt = (1 - b_val) / (c_val - b_val);
+      b.x = x + rez;
+      b.y = lerp(y, y + rez, amt);
+
+      let c = createVector();
+      amt = (1 - d_val) / (c_val - d_val);
+      c.x = lerp(x, x + rez, amt);
+      c.y = y + rez;
+      for (let i = 0; i < cols; i++) {
+        let k = [];
+        for (let j = 0; j < rows; j++) {
+          k.push(0);
+        }
+        field.push(k);
+      }
+
+      let d = createVector();
+      amt = (1 - a_val) / (d_val - a_val);
+      d.x = x;
+      d.y = lerp(y, y + rez, amt);
+
+      stroke(255);
+      strokeWeight(2);
+      switch (state) {
+        case 1:
+          drawLine(c, d);
+          break;
+        case 2:
+          drawLine(b, c);
+          break;
+        case 3:
+          drawLine(b, d);
+          break;
+        case 4:
+          drawLine(a, b);
+          break;
+        case 5:
+          drawLine(a, d);
+          drawLine(b, c);
+          break;
+        case 6:
+          drawLine(a, c);
+          break;
+        case 7:
+          drawLine(a, d);
+          break;
+        case 8:
+          drawLine(a, d);
+          break;
+        case 9:
+          drawLine(a, c);
+          break;
+        case 10:
+          drawLine(a, b);
+          drawLine(c, d);
+          break;
+        case 11:
+          drawLine(a, b);
+          break;
+        case 12:
+          drawLine(b, d);
+          break;
+        case 13:
+          drawLine(b, c);
+          break;
+        case 14:
+          drawLine(c, d);
+          break;
+      }
+    }
+  }
+}
+
+function getState(a, b, c, d) {
+  return a * 8 + b * 4 + c * 2 + d * 1;
+}