diff --git a/2025/sketch_2025_01_04/sketch_2025_01_04.png b/2025/sketch_2025_01_04/sketch_2025_01_04.png
new file mode 100644
index 00000000..7ef42243
Binary files /dev/null and b/2025/sketch_2025_01_04/sketch_2025_01_04.png differ
diff --git a/2025/sketch_2025_01_04/sketch_2025_01_04.py b/2025/sketch_2025_01_04/sketch_2025_01_04.py
new file mode 100644
index 00000000..89414cc8
--- /dev/null
+++ b/2025/sketch_2025_01_04/sketch_2025_01_04.py
@@ -0,0 +1,44 @@
+import py5
+from py5 import sin, cos, PI
+
+def setup():
+    py5.size(800, 800)
+    py5.translate(400, 400)
+    py5.background(24)
+    py5.stroke(0)
+    py5.fill(0)
+    wave(390)
+    py5.save('out.png')
+    
+def wave(r):
+    vs = circle_arc_pts(0, 0, r, 0, py5.PI)        
+    vs += reversed(circle_arc_pts(-r/2, 0, r/2, 0, py5.PI))
+    vs += reversed(circle_arc_pts(r/2, 0, r/2, 0, py5.PI))
+    with py5.begin_shape():
+        py5.vertices(vs)
+    if r > 20:
+        with py5.push_matrix():
+            py5.translate(-r/2, 0)
+            py5.rotate(py5.PI/3)
+            wave(r/2)
+            py5.rotate(-py5.PI/3)
+            py5.translate(r, 0)
+            py5.rotate(py5.PI/2)
+            wave(r/2)
+
+def circle_arc_pts(x, y, radius, start, sweep):
+    return arc_pts(x, y, radius * 2, radius * 2, start, start + sweep)
+
+def arc_pts(cx, cy, w, h, start_angle, end_angle, num_points=24):
+    sweep_angle = end_angle - start_angle
+    pts_list = []
+    step_angle = float(sweep_angle) / num_points    
+    va = start_angle
+    side = 1 if sweep_angle > 0 else -1
+    while va * side < end_angle * side or abs(va - end_angle) < 0.0001:
+        pts_list.append((cx + cos(va) * w / 2.0,
+                         cy + sin(va) * h / 2.0))
+        va += step_angle
+    return pts_list
+
+py5.run_sketch()
\ No newline at end of file
diff --git a/docs/README.md b/docs/README.md
index 72d634ba..f83d94e0 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -21,6 +21,16 @@ If you appreciate what I have been doing, you may also support my artistic work,
 2025 \| [<b>2024</b>](2024.md) \| [<b>2023</b>](2023.md) \| [<b>2022</b>](2022.md) \| [<b>2021</b>](2021.md) \| [<b>2020</b>](2020.md) \| [<b>2019</b>](2019.md) \| [<b>2018</b>](2018.md) 
 
 
+---
+
+### sketch_2025_01_04
+
+![sketch_2025_01_04](https://raw.githubusercontent.com/villares/sketch-a-day/main/2025/sketch_2025_01_04/sketch_2025_01_04.png)
+
+[sketch_2025_01_04](https://github.com/villares/sketch-a-day/tree/main/2025/sketch_2025_01_04) [[py5](https://py5coding.org/)]
+
+
+
 ---
 
 ### sketch_2025_01_03