core: Allow MorphShapes and Texts to be replaced via PlaceObject

PR #4540 allowed shapes to replace their inner art handles via
replace PlaceObject tags. This can also happen for morph shapes and
static texts.

Add MorphShape::replace_with and Text::repalce_with. This fixes the
incorrect art in main menu buttons of Super Mario 63.

core/src/display_object/graphic.rs

@@ -147,9 +147,8 @@ impl<'gc> TDisplayObject<'gc> for Graphic<'gc> {
     }
 
     fn replace_with(&self, context: &mut UpdateContext<'_, 'gc, '_>, id: CharacterId) {
-        // Only a graphic can replace themselves with another graphic via a Replace PlaceObject tag.
-        // This does not create a new graphic instance, but instead swaps out the underlying handle to point to
-        // the new art.
+        // Static assets like graphics can replace themselves via a PlaceObject tag with PlaceObjectAction::Replace.
+        // This does not create a new instance, but instead swaps out the underlying static data to point to the new art.
         if let Some(new_graphic) = context
             .library
             .library_for_movie_mut(self.movie().unwrap())

core/src/display_object/morph_shape.rs

@@ -55,6 +55,18 @@ impl<'gc> TDisplayObject<'gc> for MorphShape<'gc> {
         Some(*self)
     }
 
+    fn replace_with(&self, context: &mut UpdateContext<'_, 'gc, '_>, id: CharacterId) {
+        if let Some(new_morph_shape) = context
+            .library
+            .library_for_movie_mut(self.movie().unwrap())
+            .get_morph_shape(id)
+        {
+            self.0.write(context.gc_context).static_data = new_morph_shape.0.read().static_data;
+        } else {
+            log::warn!("PlaceObject: expected morph shape at character ID {}", id);
+        }
+    }
+
     fn run_frame(&self, _context: &mut UpdateContext) {
         // Noop
     }

core/src/display_object/text.rs

@@ -65,6 +65,18 @@ impl<'gc> TDisplayObject<'gc> for Text<'gc> {
         Some(self.0.read().static_data.swf.clone())
     }
 
+    fn replace_with(&self, context: &mut UpdateContext<'_, 'gc, '_>, id: CharacterId) {
+        if let Some(new_text) = context
+            .library
+            .library_for_movie_mut(self.movie().unwrap())
+            .get_text(id)
+        {
+            self.0.write(context.gc_context).static_data = new_text.0.read().static_data;
+        } else {
+            log::warn!("PlaceObject: expected text at character ID {}", id);
+        }
+    }
+
     fn run_frame(&self, _context: &mut UpdateContext) {
         // Noop
     }

core/src/library.rs

@@ -3,7 +3,7 @@ use crate::avm1::property_map::PropertyMap as Avm1PropertyMap;
 use crate::avm2::{Domain as Avm2Domain, Object as Avm2Object};
 use crate::backend::audio::SoundHandle;
 use crate::character::Character;
-use crate::display_object::{Bitmap, Graphic, TDisplayObject};
+use crate::display_object::{Bitmap, Graphic, MorphShape, TDisplayObject, Text};
 use crate::font::{Font, FontDescriptor};
 use crate::prelude::*;
 use crate::tag_utils::SwfMovie;
@@ -297,6 +297,16 @@ impl<'gc> MovieLibrary<'gc> {
         }
     }
 
+    /// Returns the `MorphShape` with the given character ID.
+    /// Returns `None` if the ID does not exist or is not a `MorphShape`.
+    pub fn get_morph_shape(&self, id: CharacterId) -> Option<MorphShape<'gc>> {
+        if let Some(&Character::MorphShape(morph_shape)) = self.characters.get(&id) {
+            Some(morph_shape)
+        } else {
+            None
+        }
+    }
+
     pub fn get_sound(&self, id: CharacterId) -> Option<SoundHandle> {
         if let Some(Character::Sound(sound)) = self.characters.get(&id) {
             Some(*sound)
@@ -305,6 +315,16 @@ impl<'gc> MovieLibrary<'gc> {
         }
     }
 
+    /// Returns the `Text` with the given character ID.
+    /// Returns `None` if the ID does not exist or is not a `Text`.
+    pub fn get_text(&self, id: CharacterId) -> Option<Text<'gc>> {
+        if let Some(&Character::Text(text)) = self.characters.get(&id) {
+            Some(text)
+        } else {
+            None
+        }
+    }
+
     pub fn set_jpeg_tables(&mut self, data: Vec<u8>) {
         if self.jpeg_tables.is_some() {
             // SWF spec says there should only be one JPEGTables tag.