Fixed two minor issues of :class:.SpiralIn and :class:.ManimBanner (#2688)

* passed run_time argument to SpiralIn in ManimBanner.create

* let SpiralIn respect rate_func

* make SpiralIn an introducer

Co-authored-by: Naveen M K <[email protected]>

Author: behackl

manim/animation/creation.py

@@ -459,9 +459,10 @@ def __init__(
             shape.move_to(shape.initial_position)
             shape.save_state()
 
-        super().__init__(shapes, **kwargs)
+        super().__init__(shapes, introducer=True, **kwargs)
 
     def interpolate_mobject(self, alpha: float) -> None:
+        alpha = self.rate_func(alpha)
         for shape in self.shapes:
             shape.restore()
             shape.save_state()

manim/mobject/logo.py

@@ -128,7 +128,7 @@ def create(self, run_time: float = 2) -> AnimationGroup:
             An animation to be used in a :meth:`.Scene.play` call.
         """
         return AnimationGroup(
-            SpiralIn(self.shapes),
+            SpiralIn(self.shapes, run_time=run_time),
             FadeIn(self.M, run_time=run_time / 2),
             lag_ratio=0.1,
         )