Tidying a few things up.

11 files changed, 65 insertions, 35 deletions

diff --git a/src/reel_atmos_asset.h b/src/reel_atmos_asset.h
index 2e4a8d4e..6ceec984 100644
--- a/src/reel_atmos_asset.h
+++ b/src/reel_atmos_asset.h
@@ -60,8 +60,12 @@ public:
 	ReelAtmosAsset (std::shared_ptr<AtmosAsset> asset, int64_t entry_point);
 	explicit ReelAtmosAsset (std::shared_ptr<const cxml::Node>);
 
-	std::shared_ptr<AtmosAsset> asset () const {
-		return asset_of_type<AtmosAsset> ();
+	std::shared_ptr<const AtmosAsset> asset () const {
+		return asset_of_type<const AtmosAsset>();
+	}
+
+	std::shared_ptr<AtmosAsset> asset () {
+		return asset_of_type<AtmosAsset>();
 	}
 
 	xmlpp::Node* write_to_cpl (xmlpp::Node* node, Standard standard) const override;
@@ -71,6 +75,7 @@ private:
 	boost::optional<std::string> key_type () const override {
 		return std::string("MDEK");
 	}
+
 	std::string cpl_node_name (Standard standard) const override;
 	std::pair<std::string, std::string> cpl_node_namespace () const override;
 };
diff --git a/src/reel_closed_caption_asset.h b/src/reel_closed_caption_asset.h
index a1f3b6ec..78e05659 100644
--- a/src/reel_closed_caption_asset.h
+++ b/src/reel_closed_caption_asset.h
@@ -62,12 +62,16 @@ public:
 	ReelClosedCaptionAsset (std::shared_ptr<SubtitleAsset> asset, Fraction edit_rate, int64_t instrinsic_duration, int64_t entry_point);
 	explicit ReelClosedCaptionAsset (std::shared_ptr<const cxml::Node>);
 
-	bool equals (std::shared_ptr<const ReelClosedCaptionAsset>, EqualityOptions, NoteHandler) const;
+	std::shared_ptr<const SubtitleAsset> asset () const {
+		return asset_of_type<const SubtitleAsset>();
+	}
 
-	std::shared_ptr<SubtitleAsset> asset () const {
-		return std::dynamic_pointer_cast<SubtitleAsset>(_asset_ref.asset());
+	std::shared_ptr<SubtitleAsset> asset () {
+		return asset_of_type<SubtitleAsset>();
 	}
 
+	bool equals (std::shared_ptr<const ReelClosedCaptionAsset>, EqualityOptions, NoteHandler) const;
+
 	void set_language (dcp::LanguageTag l) {
 		_language = l.to_string();
 	}
diff --git a/src/reel_interop_closed_caption_asset.h b/src/reel_interop_closed_caption_asset.h
index bb5b5cec..ec954346 100644
--- a/src/reel_interop_closed_caption_asset.h
+++ b/src/reel_interop_closed_caption_asset.h
@@ -54,12 +54,16 @@ public:
 	ReelInteropClosedCaptionAsset (std::shared_ptr<InteropSubtitleAsset> asset, Fraction edit_rate, int64_t instrinsic_duration, int64_t entry_point);
 	explicit ReelInteropClosedCaptionAsset (std::shared_ptr<const cxml::Node>);
 
-	xmlpp::Node* write_to_cpl (xmlpp::Node* node, Standard standard) const override;
+	std::shared_ptr<const InteropSubtitleAsset> interop_asset () const {
+		return asset_of_type<const InteropSubtitleAsset>();
+	}
 
-	std::shared_ptr<InteropSubtitleAsset> interop_asset () const {
-		return std::dynamic_pointer_cast<InteropSubtitleAsset>(asset());
+	std::shared_ptr<InteropSubtitleAsset> interop_asset () {
+		return asset_of_type<InteropSubtitleAsset>();
 	}
 
+	xmlpp::Node* write_to_cpl (xmlpp::Node* node, Standard standard) const override;
+
 private:
 	std::string cpl_node_name (Standard) const;
 	std::pair<std::string, std::string> cpl_node_namespace () const override;
diff --git a/src/reel_interop_subtitle_asset.h b/src/reel_interop_subtitle_asset.h
index 83a7ab25..7e90e9e0 100644
--- a/src/reel_interop_subtitle_asset.h
+++ b/src/reel_interop_subtitle_asset.h
@@ -54,8 +54,12 @@ public:
 	ReelInteropSubtitleAsset (std::shared_ptr<SubtitleAsset> asset, Fraction edit_rate, int64_t intrinsic_duration, int64_t entry_point);
 	explicit ReelInteropSubtitleAsset (std::shared_ptr<const cxml::Node>);
 
-	std::shared_ptr<InteropSubtitleAsset> interop_asset () const {
-		return std::dynamic_pointer_cast<InteropSubtitleAsset>(asset());
+	std::shared_ptr<const InteropSubtitleAsset> interop_asset () const {
+		return asset_of_type<const InteropSubtitleAsset>();
+	}
+
+	std::shared_ptr<InteropSubtitleAsset> interop_asset () {
+		return asset_of_type<InteropSubtitleAsset>();
 	}
 };
 
diff --git a/src/reel_mono_picture_asset.h b/src/reel_mono_picture_asset.h
index 9f1335be..50e904b2 100644
--- a/src/reel_mono_picture_asset.h
+++ b/src/reel_mono_picture_asset.h
@@ -62,12 +62,12 @@ public:
 
 	/** @return the MonoPictureAsset that this object refers to */
 	std::shared_ptr<const MonoPictureAsset> mono_asset () const {
-		return asset_of_type<const MonoPictureAsset> ();
+		return asset_of_type<const MonoPictureAsset>();
 	}
 
 	/** @return the MonoPictureAsset that this object refers to */
 	std::shared_ptr<MonoPictureAsset> mono_asset () {
-		return asset_of_type<MonoPictureAsset> ();
+		return asset_of_type<MonoPictureAsset>();
 	}
 
 private:
diff --git a/src/reel_picture_asset.h b/src/reel_picture_asset.h
index 5a925e24..e79c4455 100644
--- a/src/reel_picture_asset.h
+++ b/src/reel_picture_asset.h
@@ -57,19 +57,19 @@ public:
 	ReelPictureAsset (std::shared_ptr<PictureAsset> asset, int64_t entry_point);
 	explicit ReelPictureAsset (std::shared_ptr<const cxml::Node>);
 
-	virtual xmlpp::Node* write_to_cpl (xmlpp::Node* node, Standard standard) const;
-	bool equals (std::shared_ptr<const ReelPictureAsset>, EqualityOptions, NoteHandler) const;
-
 	/** @return the PictureAsset that this object refers to */
 	std::shared_ptr<const PictureAsset> asset () const {
-		return asset_of_type<const PictureAsset> ();
+		return asset_of_type<const PictureAsset>();
 	}
 
 	/** @return the PictureAsset that this object refers to */
 	std::shared_ptr<PictureAsset> asset () {
-		return asset_of_type<PictureAsset> ();
+		return asset_of_type<PictureAsset>();
 	}
 
+	virtual xmlpp::Node* write_to_cpl (xmlpp::Node* node, Standard standard) const override;
+	bool equals (std::shared_ptr<const ReelPictureAsset>, EqualityOptions, NoteHandler) const;
+
 	/** @return picture frame rate */
 	Fraction frame_rate () const {
 		return _frame_rate;
diff --git a/src/reel_smpte_closed_caption_asset.h b/src/reel_smpte_closed_caption_asset.h
index 889ce5f6..8b38d2ad 100644
--- a/src/reel_smpte_closed_caption_asset.h
+++ b/src/reel_smpte_closed_caption_asset.h
@@ -55,12 +55,17 @@ public:
 	ReelSMPTEClosedCaptionAsset (std::shared_ptr<SMPTESubtitleAsset> asset, Fraction edit_rate, int64_t instrinsic_duration, int64_t entry_point);
 	explicit ReelSMPTEClosedCaptionAsset (std::shared_ptr<const cxml::Node>);
 
-	xmlpp::Node* write_to_cpl (xmlpp::Node* node, Standard standard) const override;
+	std::shared_ptr<SMPTESubtitleAsset> smpte_asset () {
+		return asset_of_type<SMPTESubtitleAsset>();
+	}
 
-	std::shared_ptr<SMPTESubtitleAsset> smpte_asset () const {
-		return std::dynamic_pointer_cast<SMPTESubtitleAsset>(asset());
+	std::shared_ptr<const SMPTESubtitleAsset> smpte_asset () const {
+		return asset_of_type<const SMPTESubtitleAsset>();
 	}
 
+	xmlpp::Node* write_to_cpl (xmlpp::Node* node, Standard standard) const override;
+
+
 private:
 	boost::optional<std::string> key_type () const override {
 		return std::string("MDSK");
diff --git a/src/reel_smpte_subtitle_asset.h b/src/reel_smpte_subtitle_asset.h
index aaff9a98..2a097309 100644
--- a/src/reel_smpte_subtitle_asset.h
+++ b/src/reel_smpte_subtitle_asset.h
@@ -56,8 +56,12 @@ public:
 	ReelSMPTESubtitleAsset (std::shared_ptr<SMPTESubtitleAsset> asset, Fraction edit_rate, int64_t intrinsic_duration, int64_t entry_point);
 	explicit ReelSMPTESubtitleAsset (std::shared_ptr<const cxml::Node>);
 
-	std::shared_ptr<SMPTESubtitleAsset> smpte_asset () const {
-		return std::dynamic_pointer_cast<SMPTESubtitleAsset>(asset());
+	std::shared_ptr<const SMPTESubtitleAsset> smpte_asset () const {
+		return asset_of_type<const SMPTESubtitleAsset>();
+	}
+
+	std::shared_ptr<SMPTESubtitleAsset> smpte_asset () {
+		return asset_of_type<SMPTESubtitleAsset>();
 	}
 
 private:
diff --git a/src/reel_sound_asset.h b/src/reel_sound_asset.h
index 0b4d0f9d..5eee23be 100644
--- a/src/reel_sound_asset.h
+++ b/src/reel_sound_asset.h
@@ -55,17 +55,17 @@ public:
 	ReelSoundAsset (std::shared_ptr<dcp::SoundAsset> content, int64_t entry_point);
 	explicit ReelSoundAsset (std::shared_ptr<const cxml::Node>);
 
-	bool equals (std::shared_ptr<const ReelSoundAsset>, EqualityOptions, NoteHandler) const;
+	/** @return the SoundAsset that this object refers to */
+	std::shared_ptr<const SoundAsset> asset () const {
+		return asset_of_type<const SoundAsset>();
+	}
 
 	/** @return the SoundAsset that this object refers to */
 	std::shared_ptr<SoundAsset> asset () {
 		return asset_of_type<SoundAsset>();
 	}
 
-	/** @return the SoundAsset that this object refers to */
-	std::shared_ptr<const SoundAsset> asset () const {
-		return asset_of_type<const SoundAsset>();
-	}
+	bool equals (std::shared_ptr<const ReelSoundAsset>, EqualityOptions, NoteHandler) const;
 
 private:
 	boost::optional<std::string> key_type () const;
diff --git a/src/reel_stereo_picture_asset.h b/src/reel_stereo_picture_asset.h
index 7e603108..beedc4a6 100644
--- a/src/reel_stereo_picture_asset.h
+++ b/src/reel_stereo_picture_asset.h
@@ -62,12 +62,12 @@ public:
 
 	/** @return the StereoPictureAsset that this object refers to */
 	std::shared_ptr<const StereoPictureAsset> stereo_asset () const {
-		return asset_of_type<const StereoPictureAsset> ();
+		return asset_of_type<const StereoPictureAsset>();
 	}
 
 	/** @return the StereoPictureAsset that this object refers to */
 	std::shared_ptr<StereoPictureAsset> stereo_asset () {
-		return asset_of_type<StereoPictureAsset> ();
+		return asset_of_type<StereoPictureAsset>();
 	}
 
 private:
diff --git a/src/reel_subtitle_asset.h b/src/reel_subtitle_asset.h
index a4e674ba..95013d34 100644
--- a/src/reel_subtitle_asset.h
+++ b/src/reel_subtitle_asset.h
@@ -65,14 +65,18 @@ public:
 	ReelSubtitleAsset (std::shared_ptr<SubtitleAsset> asset, Fraction edit_rate, int64_t intrinsic_duration, int64_t entry_point);
 	explicit ReelSubtitleAsset (std::shared_ptr<const cxml::Node>);
 
-	xmlpp::Node* write_to_cpl (xmlpp::Node* node, Standard standard) const;
-
-	bool equals (std::shared_ptr<const ReelSubtitleAsset>, EqualityOptions, NoteHandler) const;
+	std::shared_ptr<const SubtitleAsset> asset () const {
+		return asset_of_type<const SubtitleAsset>();
+	}
 
-	std::shared_ptr<SubtitleAsset> asset () const {
-		return std::dynamic_pointer_cast<SubtitleAsset>(_asset_ref.asset());
+	std::shared_ptr<SubtitleAsset> asset () {
+		return asset_of_type<SubtitleAsset>();
 	}
 
+	xmlpp::Node* write_to_cpl (xmlpp::Node* node, Standard standard) const override;
+
+	bool equals (std::shared_ptr<const ReelSubtitleAsset>, EqualityOptions, NoteHandler) const;
+
 	void set_language (dcp::LanguageTag language);
 
 	boost::optional<std::string> language () const {
@@ -89,7 +93,7 @@ protected:
 private:
 	friend struct ::verify_invalid_language1;
 
-	std::string cpl_node_name (Standard standard) const;
+	std::string cpl_node_name (Standard standard) const override;
 };