// Copyright (C) 2002-2009 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

#ifndef __I_CAMERA_SCENE_NODE_H_INCLUDED__
#define __I_CAMERA_SCENE_NODE_H_INCLUDED__

#include "ISceneNode.h"
#include "IEventReceiver.h"

namespace irr
{
namespace scene
{
	struct SViewFrustum;

	//! Scene Node which is a (controlable) camera.
	/** The whole scene will be rendered from the cameras point of view.
	Because the ICameraScenNode is a SceneNode, it can be attached to any
	other scene node, and will follow its parents movement, rotation and so
	on.
	*/
	class ICameraSceneNode : public ISceneNode, public IEventReceiver
	{
	public:

		//! Constructor
		ICameraSceneNode(ISceneNode* parent, ISceneManager* mgr, s32 id,
			const core::vector3df& position = core::vector3df(0,0,0),
			const core::vector3df& rotation = core::vector3df(0,0,0),
			const core::vector3df& scale = core::vector3df(1.0f,1.0f,1.0f))
			: ISceneNode(parent, mgr, id, position, rotation, scale), IsOrthogonal(false) {}

		//! Sets the projection matrix of the camera.
		/** The core::matrix4 class has some methods to build a
		projection matrix. e.g:
		core::matrix4::buildProjectionMatrixPerspectiveFovLH.
		Note that the matrix will only stay as set by this method until
		one of the following Methods are called: setNearValue,
		setFarValue, setAspectRatio, setFOV.
		\param projection The new projection matrix of the camera.
		\param isOrthogonal Set this to true if the matrix is an
		orthogonal one (e.g. from matrix4::buildProjectionMatrixOrtho).
		*/
		virtual void setProjectionMatrix(const core::matrix4& projection, bool isOrthogonal = false) = 0;

		//! Gets the current projection matrix of the camera.
		/** \return The current projection matrix of the camera. */
		virtual const core::matrix4& getProjectionMatrix() const = 0;

		//! Gets the current view matrix of the camera.
		/** \return The current view matrix of the camera. */
		virtual const core::matrix4& getViewMatrix() const = 0;

		//! It is possible to send mouse and key events to the camera.
		/** Most cameras may ignore this input, but camera scene nodes
		which are created for example with
		ISceneManager::addCameraSceneNodeMaya or
		ISceneManager::addCameraSceneNodeFPS, may want to get
		this input for changing their position, look at target or
		whatever. */
		virtual bool OnEvent(const SEvent& event) = 0;

		//! Sets the look at target of the camera
		/** If the camera's target and rotation are bound ( @see
		bindTargetAndRotation() ) then calling this will also change
		the camera's scene node rotation to match the target.
		\param pos Look at target of the camera, in world co-ordinates. */
		virtual void setTarget(const core::vector3df& pos) = 0;

		//! Sets the rotation of the node.
		/** This only modifies the relative rotation of the node.
		If the camera's target and rotation are bound ( @see
		bindTargetAndRotation() ) then calling this will also change
		the camera's target to match the rotation.
		\param rotation New rotation of the node in degrees. */
		virtual void setRotation(const core::vector3df& rotation) = 0;

		//! Gets the current look at target of the camera
		/** \return The current look at target of the camera, in world co-ordinates */
		virtual const core::vector3df& getTarget() const = 0;

		//! Sets the up vector of the camera.
		/** \param pos: New upvector of the camera. */
		virtual void setUpVector(const core::vector3df& pos) = 0;

		//! Gets the up vector of the camera.
		/** \return The up vector of the camera, in world space. */
		virtual const core::vector3df& getUpVector() const = 0;

		//! Gets the value of the near plane of the camera.
		/** \return The value of the near plane of the camera. */
		virtual f32 getNearValue() const = 0;

		//! Gets the value of the far plane of the camera.
		/** \return The value of the far plane of the camera. */
		virtual f32 getFarValue() const = 0;

		//! Gets the aspect ratio of the camera.
		/** \return The aspect ratio of the camera. */
		virtual f32 getAspectRatio() const = 0;

		//! Gets the field of view of the camera.
		/** \return The field of view of the camera in radiants. */
		virtual f32 getFOV() const = 0;

		//! Sets the value of the near clipping plane. (default: 1.0f)
		/** \param zn: New z near value. */
		virtual void setNearValue(f32 zn) = 0;

		//! Sets the value of the far clipping plane (default: 2000.0f)
		/** \param zf: New z far value. */
		virtual void setFarValue(f32 zf) = 0;

		//! Sets the aspect ratio (default: 4.0f / 3.0f)
		/** \param aspect: New aspect ratio. */
		virtual void setAspectRatio(f32 aspect) = 0;

		//! Sets the field of view (Default: PI / 2.5f)
		/** \param fovy: New field of view in radiants. */
		virtual void setFOV(f32 fovy) = 0;

		//! Get the view frustum.
		/** Needed sometimes by bspTree or LOD render nodes.
		\return The current view frustum. */
		virtual const SViewFrustum* getViewFrustum() const = 0;

		//! Disables or enables the camera to get key or mouse inputs.
		/** If this is set to true, the camera will respond to key
		inputs otherwise not. */
		virtual void setInputReceiverEnabled(bool enabled) = 0;

		//! Checks if the input receiver of the camera is currently enabled.
		virtual bool isInputReceiverEnabled() const = 0;

		//! Checks if a camera is orthogonal.
		virtual bool isOrthogonal() const
		{
			_IRR_IMPLEMENT_MANAGED_MARSHALLING_BUGFIX;
			return IsOrthogonal;
		}

		//! Binds the camera scene node's rotation to its target position and vice vera, or unbinds them.
		/** When bound, calling setRotation() will update the camera's
		target position to be along its +Z axis, and likewise calling
		setTarget() will update its rotation so that its +Z axis will
		point at the target point. FPS camera use this binding by
		default; other cameras do not.
		\param bound True to bind the camera's scene node rotation
		and targetting, false to unbind them.
		@see getTargetAndRotationBinding() */
		virtual void bindTargetAndRotation(bool bound) = 0;

		//! Queries if the camera scene node's rotation and its target position are bound together.
		/** @see bindTargetAndRotation() */
		virtual bool getTargetAndRotationBinding(void) const = 0;

	protected:

		bool IsOrthogonal;
	};

} // end namespace scene
} // end namespace irr

#endif

