diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2064f14..ad4e83b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -4,7 +4,7 @@ on:
   push:
     branches:
       - main
-      # - develop
+      - develop
     paths-ignore:
       - '**/README.md'
       - '**/CHANGELOG.md'
diff --git a/CHANGELOG.md b/CHANGELOG.md
index d59920f..f0445cd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,7 @@
 - Add `vf/entity-debug` and `vf/systems-debug`
 - Add `vj/ContactManifold`
 - Improve error for VybeC compilation
+- Add `mixer.fs`
 
 ## v0.7.444
 
diff --git a/resources/com/pfeodrippe/vybe/shaders/mixer.fs b/resources/com/pfeodrippe/vybe/shaders/mixer.fs
index 81d83b4..740185f 100644
--- a/resources/com/pfeodrippe/vybe/shaders/mixer.fs
+++ b/resources/com/pfeodrippe/vybe/shaders/mixer.fs
@@ -7,20 +7,81 @@ in vec4 fragColor;
 uniform sampler2D texture0;
 uniform sampler2D texture1;
 uniform vec4 colDiffuse;
-uniform float edge_fill;
+uniform float u_fill;
+uniform float u_time;
 
 // Output fragment color
 out vec4 finalColor;
 
+bool fill_whole(vec2 st) {
+    float c = 1.0;
+    bool trigger =
+        st.x * st.y < sin(u_fill * 0.87 * c) * cos(u_fill * 0.23 * c) + sin(u_fill * 0.37 * c) * cos(u_fill * 0.53 * c)
+        //st.x > sin(u_fill * 0.24) * 1.0 && st.x < sin(u_fill * 0.87 * c) &&
+        //st.y > sin(u_fill * 0.41 * c) * 0.4 && st.y < sin(u_fill * 0.46 * c)
+        ;
+
+    return trigger;
+}
+
+bool fill_blob(vec2 st) {
+    if (u_fill < -0.5) return false;
+
+    float c = 0.5;
+    bool trigger = false;
+
+    float t = sin(u_time * 0.8) * 0.1;
+    float r = u_fill * 0.5 + t;
+
+
+    // Circle.
+    if ((st.x - c) * (st.x - c) + (st.y - c) * (st.y - c) < r/5.0) {
+        trigger = true;
+    }
+
+    // Square.
+    // if (st.x - 0.5 < 0.25 * u_fill && st.y - 0.5 < 0.25 * u_fill &&
+    //     st.x - 0.5 > -0.25 * u_fill && st.y - 0.5 > -0.25 * u_fill) {
+    //     trigger = true;
+    // }
+
+    /*
+    if ((sin(st.x + cos(u_time*0.532) * 0.05) - c) * (sin(st.x + cos(u_time*0.3) * 0.04) - c) +
+        (sin(st.y + sin(u_time * 0.2) * 0.145) - c) * (sin(st.y + sin(u_time * 0.153) * 0.1) - c)
+        < r/1.0 * st.x * st.y * cos(st.x * u_time * 0.1) * sin(st.y * u_time * 0.2)) {
+        trigger = true;
+    }
+    */
+
+    /*
+    if ((sin(st.x + cos(u_time*0.532) * 0.05) - c) * (sin(st.x + cos(u_time*0.3) * 0.04) - c) +
+        (sin(st.y + sin(u_time * 0.2) * 0.145) - c) * (sin(st.y + sin(u_time * 0.153) * 0.1) - c)
+        < r/8.0) {
+        trigger = true;
+    }
+    */
+
+    // dots
+    /*
+    if ((st.x - c) * (st.x - c) + (st.y - c) * (st.y - c) < r/5.0) {
+        if (sin(st.y*99999.0) > 0.0001 && cos(st.x*100000.0) > 0.0001) {
+            trigger = true;
+        } else {
+            trigger = false;
+        }
+    }
+    */
+
+    return trigger;
+}
+
 void main (void) {
     vec2 st = fragTexCoord;
-    // Higher radius is like an out of focus effect.
-    float radius = 1.1;
 
-    float c = 1.0;bool trigger =
-        st.x * st.y < sin(edge_fill * 0.87 * c) * cos(edge_fill * 0.23 * c) + sin(edge_fill * 0.37 * c) * cos(edge_fill * 0.53 * c)
-        //st.x > sin(edge_fill * 0.24) * 1.0 && st.x < sin(edge_fill * 0.87 * c) &&
-        //st.y > sin(edge_fill * 0.41 * c) * 0.4 && st.y < sin(edge_fill * 0.46 * c)
+    float c = 1.0;
+    bool trigger =
+        //fill_whole(st)
+        fill_blob(st)
         ;
 
     if (trigger) {
diff --git a/resources/shaders/edge_2d.fs b/resources/shaders/edge_2d.fs
index 087766b..965f9f4 100644
--- a/resources/shaders/edge_2d.fs
+++ b/resources/shaders/edge_2d.fs
@@ -45,7 +45,8 @@ void main (void) {
             finalColor = texelColor*colDiffuse*fragColor;
         } else {
             finalColor = vec4(color,1.0);
-        }*/
+        }
+        */
 
         finalColor = vec4(color, 1.0);
     } else {
diff --git a/todo.md b/todo.md
index cd0f89d..3253d1e 100644
--- a/todo.md
+++ b/todo.md
@@ -240,17 +240,20 @@
     - [x] portion of the window
     - [x] only when cube clicked
     - [x] LPF when enabled
-    - [ ] 2 worlds
-      - [ ] different objects
+    - [x] 2 worlds
+      - [x] different objects
         - [x] disable/enable object
         - [x] render to another RT
         - [x] shader to mix the RTs
-        - [ ] transition from a blob
-        - [ ] multiple worlds, render twice?
-        - [ ] 2-player where you pass one object to the other?
-      - [ ] one in english, another in french?
-    - [ ] 3d?
+    - [ ] transition from a blob
+      - [ ] square
+      - [ ] circle
+    - [ ] animate blob
+- [ ] multiple worlds, render twice?
+  - [ ] 2-player where you pass one object to the other?
+  - [ ] 3d?
   - [ ] mechanic
+  - [ ] one in english, another in french?
 - [ ] ambisonics
   - [ ] 2 sources
   - [ ] system