diff --git a/2019/sketch_190820a/sketch_190820a.gif b/2019/sketch_190820a/sketch_190820a.gif
new file mode 100644
index 00000000..427be96a
Binary files /dev/null and b/2019/sketch_190820a/sketch_190820a.gif differ
diff --git a/2019/sketch_190820a/sketch_190820a.pyde b/2019/sketch_190820a/sketch_190820a.pyde
index 3d7be7b6..6ea8918c 100644
--- a/2019/sketch_190820a/sketch_190820a.pyde
+++ b/2019/sketch_190820a/sketch_190820a.pyde
@@ -1,14 +1,15 @@
 # based on https://twitter.com/Hau_kun/status/1163867191252410368?s=20
 
-p,s=[[0]*4 for _ in range(99)],720
+s,p,r=720,[[360]*4 for _ in range(99)],random
 def setup():size(s,s);colorMode(HSB)
 def draw():
  clear()
  for f in p:
   x,y,z,w=f   
-  a,d,r=atan2(w-y,z-x),dist(*f)/100,random
-  f[2:4]=[r(s)if d<1 else z,r(s)if d<1 else w]
-  f[0]+=cos(a)*d
-  f[1]+=sin(a)*d
+  a,d=atan2(w-y,z-x),dist(*f)/100
+  f[2:4]=r(s)if d<1 else z,r(s)if d<1 else w
+  f[0:2]=x+cos(a)*d,y+sin(a)*d
   fill(d*50,s,s)
   circle(x,y,10)
+ # if frameCount % 3 == 0:
+ #  saveFrame("#####.png")
diff --git a/2019/sketch_190821c/sketch_190821c.png b/2019/sketch_190821c/sketch_190821c.png
new file mode 100644
index 00000000..90431c58
Binary files /dev/null and b/2019/sketch_190821c/sketch_190821c.png differ
diff --git a/2019/sketch_190821c/sketch_190821c.pyde b/2019/sketch_190821c/sketch_190821c.pyde
new file mode 100644
index 00000000..1ee98086
--- /dev/null
+++ b/2019/sketch_190821c/sketch_190821c.pyde
@@ -0,0 +1,66 @@
+add_library('pdf')
+linhas = []
+divisoes = 5
+salvar_pdf = False
+ponto_clique = []
+
+def setup():
+    size(500, 500)
+
+def draw():
+    if salvar_pdf:
+        beginRecord(PDF, "####.pdf")
+
+    stroke(255)  # traço branco
+    strokeWeight(10)  # espessura do traço ("peso")
+    mh, mv = width / 2, height / 2
+    translate(mh, mv)
+    background(0, 128, 32)  # verde (mude a sua cor!)
+
+    for num in range(divisoes):
+        rotate(radians(360 / divisoes))
+        for linha in linhas:
+            x1, y1, x2, y2 = linha
+            line(x1 - mh, y1 - mv, x2 - mh, y2 - mv)
+            scale(1, -1)
+            line(x1 - mh, y1 - mv, x2 - mh, y2 - mv)
+            scale(1, -1)
+
+    if salvar_pdf:
+        endRecord()
+        global salvar_pdf
+        salvar_pdf = False
+
+    if ponto_clique:
+        for num in range(divisoes):
+            rotate(radians(360 / divisoes))
+            line(ponto_clique[0] - mh, ponto_clique[1] - mv,
+                 mouseX - mh, mouseY - mv)
+            scale(1, -1)
+            line(ponto_clique[0] - mh, ponto_clique[1] - mv,
+                 mouseX - mh, mouseY - mv)
+            scale(1, -1)
+
+def mousePressed():  # def mouseDragged():
+    if ponto_clique:
+        px, py = ponto_clique
+        linhas.append((px, py, mouseX, mouseY))
+    if mouseButton == LEFT:
+        ponto_clique[:] = mouseX, mouseY
+    elif mouseButton == RIGHT:
+        ponto_clique[:] = []
+
+def keyPressed():
+    if key == "a":
+        linhas[:] = []  # esvazia lista de linhas
+        ponto_clique[:] = []
+    if key == "g":
+        saveFrame("#####.png")
+        print("salvando PNG")
+    if key == "p":
+        global salvar_pdf
+        salvar_pdf = True
+        print("salvando PDF")
+    if keyCode == BACKSPACE and linhas:
+        linhas[:] = linha[:-1]
+