Add First Person Attachments (#10360)

Fixes some other third person camera specific attachments.
Implements a single new flag for entities to be forced visible in first person mode.
Old mods do not need to be updated to use the new flag and are fully backwards compatible.

4 files changed, 20 insertions, 15 deletions

diff --git a/src/server/luaentity_sao.cpp b/src/server/luaentity_sao.cpp
index f20914f7f..b39797531 100644
--- a/src/server/luaentity_sao.cpp
+++ b/src/server/luaentity_sao.cpp
@@ -238,9 +238,9 @@ std::string LuaEntitySAO::getClientInitializationData(u16 protocol_version)
 	msg_os << serializeString32(generateUpdateAnimationCommand()); // 3
 	for (const auto &bone_pos : m_bone_position) {
 		msg_os << serializeString32(generateUpdateBonePositionCommand(
-			bone_pos.first, bone_pos.second.X, bone_pos.second.Y)); // m_bone_position.size
+			bone_pos.first, bone_pos.second.X, bone_pos.second.Y)); // 3 + N
 	}
-	msg_os << serializeString32(generateUpdateAttachmentCommand()); // 4
+	msg_os << serializeString32(generateUpdateAttachmentCommand()); // 4 + m_bone_position.size
 
 	int message_count = 4 + m_bone_position.size();
 
diff --git a/src/server/player_sao.cpp b/src/server/player_sao.cpp
index 8d4938c3c..344d18a20 100644
--- a/src/server/player_sao.cpp
+++ b/src/server/player_sao.cpp
@@ -122,10 +122,10 @@ std::string PlayerSAO::getClientInitializationData(u16 protocol_version)
 	msg_os << serializeString32(generateUpdateAnimationCommand()); // 3
 	for (const auto &bone_pos : m_bone_position) {
 		msg_os << serializeString32(generateUpdateBonePositionCommand(
-			bone_pos.first, bone_pos.second.X, bone_pos.second.Y)); // m_bone_position.size
+			bone_pos.first, bone_pos.second.X, bone_pos.second.Y)); // 3 + N
 	}
-	msg_os << serializeString32(generateUpdateAttachmentCommand()); // 4
-	msg_os << serializeString32(generateUpdatePhysicsOverrideCommand()); // 5
+	msg_os << serializeString32(generateUpdateAttachmentCommand()); // 4 + m_bone_position.size
+	msg_os << serializeString32(generateUpdatePhysicsOverrideCommand()); // 5 + m_bone_position.size
 
 	int message_count = 5 + m_bone_position.size();
 
@@ -569,7 +569,8 @@ bool PlayerSAO::checkMovementCheat()
 			int parent_id;
 			std::string bone;
 			v3f attachment_rot;
-			getAttachment(&parent_id, &bone, &attachment_pos, &attachment_rot);
+			bool force_visible;
+			getAttachment(&parent_id, &bone, &attachment_pos, &attachment_rot, &force_visible);
 		}
 
 		v3f parent_pos = parent->getBasePosition();
diff --git a/src/server/unit_sao.cpp b/src/server/unit_sao.cpp
index d906e885e..2371640ca 100644
--- a/src/server/unit_sao.cpp
+++ b/src/server/unit_sao.cpp
@@ -121,8 +121,8 @@ void UnitSAO::sendOutdatedData()
 }
 // clang-format on
 
-void UnitSAO::setAttachment(
-		int parent_id, const std::string &bone, v3f position, v3f rotation)
+void UnitSAO::setAttachment(int parent_id, const std::string &bone, v3f position,
+		v3f rotation, bool force_visible)
 {
 	// Attachments need to be handled on both the server and client.
 	// If we just attach on the server, we can only copy the position of the parent.
@@ -137,6 +137,7 @@ void UnitSAO::setAttachment(
 	m_attachment_bone = bone;
 	m_attachment_position = position;
 	m_attachment_rotation = rotation;
+	m_force_visible = force_visible;
 	m_attachment_sent = false;
 
 	if (parent_id != old_parent) {
@@ -145,13 +146,14 @@ void UnitSAO::setAttachment(
 	}
 }
 
-void UnitSAO::getAttachment(
-		int *parent_id, std::string *bone, v3f *position, v3f *rotation) const
+void UnitSAO::getAttachment(int *parent_id, std::string *bone, v3f *position,
+		v3f *rotation, bool *force_visible) const
 {
 	*parent_id = m_attachment_parent_id;
 	*bone = m_attachment_bone;
 	*position = m_attachment_position;
 	*rotation = m_attachment_rotation;
+	*force_visible = m_force_visible;
 }
 
 void UnitSAO::clearChildAttachments()
@@ -159,7 +161,7 @@ void UnitSAO::clearChildAttachments()
 	for (int child_id : m_attachment_child_ids) {
 		// Child can be NULL if it was deleted earlier
 		if (ServerActiveObject *child = m_env->getActiveObject(child_id))
-			child->setAttachment(0, "", v3f(0, 0, 0), v3f(0, 0, 0));
+			child->setAttachment(0, "", v3f(0, 0, 0), v3f(0, 0, 0), false);
 	}
 	m_attachment_child_ids.clear();
 }
@@ -169,9 +171,9 @@ void UnitSAO::clearParentAttachment()
 	ServerActiveObject *parent = nullptr;
 	if (m_attachment_parent_id) {
 		parent = m_env->getActiveObject(m_attachment_parent_id);
-		setAttachment(0, "", m_attachment_position, m_attachment_rotation);
+		setAttachment(0, "", m_attachment_position, m_attachment_rotation, false);
 	} else {
-		setAttachment(0, "", v3f(0, 0, 0), v3f(0, 0, 0));
+		setAttachment(0, "", v3f(0, 0, 0), v3f(0, 0, 0), false);
 	}
 	// Do it
 	if (parent)
@@ -245,6 +247,7 @@ std::string UnitSAO::generateUpdateAttachmentCommand() const
 	os << serializeString16(m_attachment_bone);
 	writeV3F32(os, m_attachment_position);
 	writeV3F32(os, m_attachment_rotation);
+	writeU8(os, m_force_visible);
 	return os.str();
 }
 
diff --git a/src/server/unit_sao.h b/src/server/unit_sao.h
index 3cb7f0ad5..a21e055c5 100644
--- a/src/server/unit_sao.h
+++ b/src/server/unit_sao.h
@@ -64,9 +64,9 @@ public:
 	ServerActiveObject *getParent() const;
 	inline bool isAttached() const { return getParent(); }
 	void setAttachment(int parent_id, const std::string &bone, v3f position,
-			v3f rotation);
+			v3f rotation, bool force_visible);
 	void getAttachment(int *parent_id, std::string *bone, v3f *position,
-			v3f *rotation) const;
+			v3f *rotation, bool *force_visible) const;
 	void clearChildAttachments();
 	void clearParentAttachment();
 	void addAttachmentChild(int child_id);
@@ -133,4 +133,5 @@ private:
 	v3f m_attachment_position;
 	v3f m_attachment_rotation;
 	bool m_attachment_sent = false;
+	bool m_force_visible = false;
 };