Tried to make it faster but now it doesnt run.

falling_sand.py

@@ -103,6 +103,7 @@ class FallingSand:
         setattr(self.settings, "save", lambda: save_dataclass_json(self.settings, "settings.json"))
 
         self.fps = self.settings.fps
+        self.sand_particles = []
         self.falling_sand_particles = []
         self.rainbow_data = [[255, 40, 40], 0]
         self.rainbow_steps = [(1, True), (0, False), (2, True), (1, False), (0, True), (2, False)]
@@ -152,8 +153,7 @@ class FallingSand:
         if not self.running:
             return
 
-        for particle in self.falling_sand_particles:
+        self.update_sand_particles()
-            particle.update()
 
         self.matrix.close()
 
@@ -197,6 +197,74 @@ class FallingSand:
         self.sand_surface.blit(old_sand_surface, (0, 0))
         self.matrix = pygame.PixelArray(self.sand_surface)
 
+    def update_sand_particles(self):
+        i = 0
+
+        for particle in self.falling_sand_particles:
+            old_pos, color, not_moving = particle
+            ox, oy = old_pos
+
+            if oy >= self.sand_surface.get_height() - 4:
+                self.falling_sand_particles.remove(particle)
+                break
+
+            print(len(self.falling_sand_particles))
+
+            x, y = old_pos
+
+            if self.matrix[ox, oy + 1] == self.sand_surface.map_rgb(self.gray):
+                y += 1
+
+            elif (
+                    self.matrix[ox - 1, oy + 2] == self.sand_surface.map_rgb(self.gray)
+                    and self.matrix[ox + 1, oy + 2] == self.sand_surface.map_rgb(self.gray)
+            ):
+                if true_false_random():
+                    x -= 1
+                    y += 2
+
+                else:
+                    x += 1
+                    y += 2
+
+            elif self.matrix[ox - 1, oy + 2] == self.sand_surface.map_rgb(self.gray):
+                x -= 1
+                y += 2
+
+            elif self.matrix[ox + 1, oy + 2] == self.sand_surface.map_rgb(self.gray):
+                x += 1
+                y += 2
+
+            else:
+                if not_moving == 32:
+                    if self.mouse_pressed[0]:
+                        not_moving = 0
+
+                    else:
+                        self.falling_sand_particles.remove(particle)
+
+                    break
+
+                else:
+                    if self.mouse_pressed[0]:
+                        not_moving = 0
+
+                    else:
+                        not_moving += 1
+
+                    break
+
+            not_moving = 0
+            pos = (x, y)
+
+            self.falling_sand_particles.pop(i)
+            self.falling_sand_particles.append((pos, color, not_moving))
+
+            self.matrix[ox, oy] = self.gray
+            self.matrix[x, y] = color
+
+            i += 1
+
     def spawn_sand(self, position):
         for ax in range(-8, 9):
             color = self.rainbow()
@@ -207,7 +275,7 @@ class FallingSand:
                 by += ay
 
                 if self.matrix[bx, by] == self.sand_surface.map_rgb(self.gray) and bx % 2 == 0 and by % 2 == 0:
-                    self.falling_sand_particles.append(FallingSandParticle(self, (bx, by), color))
+                    self.falling_sand_particles.append(((bx, by), color, 0))  # pos, color, not_moving
 
     def rainbow(self):
         color = self.rainbow_data[0]