crown-engine/engine/SceneGraph.h

/*
Copyright (c) 2013 Daniele Bartolini, Michele Rossi
Copyright (c) 2012 Daniele Bartolini, Simone Boscaratto

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
*/

#pragma once

#include "Types.h"
#include "Matrix4x4.h"
#include "List.h"

namespace crown
{

struct SceneGraph
{
					SceneGraph();

	/// Creates a new node with @a parent parent at position @a pos and rotation @a rot.
	/// @note
	/// The @a parent node must be either -1 (meaning no parent), or an index lesser
	/// than the being created node.
	int32_t			create_node(int32_t parent, const Vector3& pos, const Quaternion& rot);

	/// Links the @a child node to the @a parent node.
	/// After the linking the @a child pose is reset to identity.
	/// @note
	/// The @a parent node must be either -1 (meaning no parent), or an index lesser than child
	void			link(int32_t child, int32_t parent);

	/// Unlinks the @a child node from its parent if it has any.
	/// After unlinking, the @child local pose is set to its previous world pose.
	void			unlink(int32_t child);

	void			set_local_position(int32_t node, const Vector3& pos);
	void			set_local_rotation(int32_t node, const Quaternion& rot);
	void			set_local_pose(int32_t node, const Matrix4x4& pose);

	Vector3			local_position(int32_t node) const;
	Quaternion		local_rotation(int32_t node) const;
	Matrix4x4		local_pose(int32_t node) const;

	Vector3			world_position(int32_t node) const;
	Quaternion		world_rotation(int32_t node) const;
	Matrix4x4		world_pose(int32_t node) const;

	// Clears the content of the scene graph.
	void			clear();

	/// Transforms local poses to world poses.
	void			update();

public:

	List<Matrix4x4>	m_world_poses;
	List<Matrix4x4>	m_local_poses;
	List<int32_t>	m_parents;
};

} // namespace crown