anki-3d-engine/include/anki/collision/CompoundShape.h

// Copyright (C) 2009-2016, Panagiotis Christopoulos Charitos.
// All rights reserved.
// Code licensed under the BSD License.
// http://www.anki3d.org/LICENSE

#pragma once

#include <anki/collision/CollisionShape.h>
#include <anki/util/NonCopyable.h>

namespace anki
{

/// @addtogroup collision
/// @{

/// A shape that contains other shapes
class CompoundShape : public CollisionShape, public NonCopyable
{
public:
	static Bool classof(const CollisionShape& c)
	{
		return c.getType() == Type::COMPOUND;
	}

	CompoundShape();

	/// Implements CollisionShape::testPlane
	F32 testPlane(const Plane& p) const;

	/// Implements CollisionShape::transform
	void transform(const Transform& trf);

	/// Implements CollisionShape::computeAabb
	void computeAabb(Aabb& b) const;

	/// Implements CollisionShape::accept
	void accept(MutableVisitor& v);

	/// Implements CollisionShape::accept
	void accept(ConstVisitor& v) const;

	/// The compound shape will not take ownership of the object
	void addShape(CollisionShape* shape);

	template<typename TFunc>
	ANKI_USE_RESULT Error iterateShapes(TFunc f) const;

private:
	static const U SHAPES_PER_CHUNK_COUNT = 8;

	class Chunk
	{
	public:
		Array<CollisionShape*, SHAPES_PER_CHUNK_COUNT> m_shapes;
		Chunk* m_next = nullptr;
	};

	Chunk m_dflt;
};

//==============================================================================
template<typename TFunc>
Error CompoundShape::iterateShapes(TFunc f) const
{
	Error err = ErrorCode::NONE;
	U count = 0;
	const Chunk* chunk = &m_dflt;

	do
	{
		U idx = SHAPES_PER_CHUNK_COUNT;
		while(idx-- != 0)
		{
			if(chunk->m_shapes[idx])
			{
				err = f(*const_cast<CollisionShape*>(chunk->m_shapes[idx]));
				if(err)
				{
					return err;
				}
				++count;
			}
		}

		chunk = chunk->m_next;
	} while(chunk);

	ANKI_ASSERT(count > 0 && "Empty CompoundShape");
	(void)count;
	return err;
}
/// @}

} // end namespace anki