/*

-----------------------------------------------------------------------------

This source file is part of OGRE

    (Object-oriented Graphics Rendering Engine)

For the latest info, see http://www.ogre3d.org

Copyright (c) 2000-2014 Torus Knot Software Ltd

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.

-----------------------------------------------------------------------------

*/

#include "OgreStableHeaders.h"

#include "OgreViewport.h"

#include "OgreMovablePlane.h"

namespace Ogre {

    const String MOT_CAMERA = "Camera";

    //-----------------------------------------------------------------------

    Camera::Camera( const String& name, SceneManager* sm)

        : Frustum(name),

        mWindowSet(false),

        mAutoAspectRatio(false),

        mUseRenderingDistance(true),

        mUseMinPixelSize(false),

#ifdef OGRE_NODELESS_POSITIONING

        mOrientation(Quaternion::IDENTITY),

        mPosition(Vector3::ZERO),

        mAutoTrackTarget(0),

        mAutoTrackOffset(Vector3::ZERO),

#endif

        mSceneLodFactor(1.0f),

        mSceneLodFactorInv(1.0f),

        mLastViewport(0),

        mCullFrustum(0),

        mLodCamera(0),

        mPixelDisplayRatio(0),

        mSortMode(SM_DISTANCE),

        mSceneDetail(PM_SOLID)

    {

        // Reasonable defaults to camera params

        mFOVy = Radian(Math::PI/4.0f);

        mNearDist = 100.0f;

        mFarDist = 100000.0f;

        mAspect = 1.33333333333333f;

        mProjType = PT_PERSPECTIVE;

#ifdef OGRE_NODELESS_POSITIONING

        mYawFixed = true; // Default to fixed yaw, like freelook since most people expect this

        mYawFixedAxis = Vector3::UNIT_Y;

#endif

        invalidateFrustum();

        invalidateView();

        // Init matrices

        mViewMatrix = Affine3::ZERO;

        mParentNode = 0;

        // no reflection

        mReflect = false;

        mVisible = false;

        mManager = sm;

    }

    //-----------------------------------------------------------------------

    Camera::~Camera()

    {

        ListenerList listenersCopy = mListeners;

        for (auto & i : listenersCopy)

        {

            i->cameraDestroyed(this);

        }

    }

    //-----------------------------------------------------------------------

    SceneManager* Camera::getSceneManager(void) const

    {

        return mManager;

    }

    //-----------------------------------------------------------------------

    void Camera::setPolygonMode(PolygonMode sd)

    {

        mSceneDetail = sd;

    }

    //-----------------------------------------------------------------------

    PolygonMode Camera::getPolygonMode(void) const

    {

        return mSceneDetail;

    }

#ifdef OGRE_NODELESS_POSITIONING

    //-----------------------------------------------------------------------

    void Camera::setPosition(Real x, Real y, Real z)

    {

        mPosition.x = x;

        mPosition.y = y;

        mPosition.z = z;

        invalidateView();

    }

    //-----------------------------------------------------------------------

    void Camera::setPosition(const Vector3& vec)

    {

        mPosition = vec;

        invalidateView();

    }

    //-----------------------------------------------------------------------

    const Vector3& Camera::getPosition(void) const

    {

        return mPosition;

    }

    //-----------------------------------------------------------------------

    void Camera::move(const Vector3& vec)

    {

        mPosition = mPosition + vec;

        invalidateView();

    }

    //-----------------------------------------------------------------------

    void Camera::moveRelative(const Vector3& vec)

    {

        // Transform the axes of the relative vector by camera's local axes

        Vector3 trans = mOrientation * vec;

        mPosition = mPosition + trans;

        invalidateView();

    }

    //-----------------------------------------------------------------------

    void Camera::setDirection(Real x, Real y, Real z)

    {

        OGRE_IGNORE_DEPRECATED_BEGIN

        setDirection(Vector3(x,y,z));

        OGRE_IGNORE_DEPRECATED_END

    }

    //-----------------------------------------------------------------------

    void Camera::setDirection(const Vector3& vec)

    {

        // Do nothing if given a zero vector

        // (Replaced assert since this could happen with auto tracking camera and

        //  camera passes through the lookAt point)

        if (vec == Vector3::ZERO) return;

        // Remember, camera points down -Z of local axes!

        // Therefore reverse direction of direction vector before determining local Z

        Vector3 zAdjustVec = -vec;

        zAdjustVec.normalise();

        Quaternion targetWorldOrientation;

        if( mYawFixed )

        {

            targetWorldOrientation = Math::lookRotation(zAdjustVec, mYawFixedAxis);

        }

        else

        {

            // Get axes from current quaternion

            Vector3 axes[3];

            updateView();

            mRealOrientation.ToAxes(axes);

            Quaternion rotQuat;

            if ( (axes[2]+zAdjustVec).squaredLength() <  0.00005f) 

            {

                // Oops, a 180 degree turn (infinite possible rotation axes)

                // Default to yaw i.e. use current UP

                rotQuat.FromAngleAxis(Radian(Math::PI), axes[1]);

            }

            else

            {

                // Derive shortest arc to new direction

                rotQuat = axes[2].getRotationTo(zAdjustVec);

            }

            targetWorldOrientation = rotQuat * mRealOrientation;

        }

        // transform to parent space

        if (mParentNode)

        {

            mOrientation = mParentNode->convertWorldToLocalOrientation(targetWorldOrientation);

        }

        else

        {

            mOrientation = targetWorldOrientation;

        }

        // TODO If we have a fixed yaw axis, we mustn't break it by using the

        // shortest arc because this will sometimes cause a relative yaw

        // which will tip the camera

        invalidateView();

    }

    //-----------------------------------------------------------------------

    Vector3 Camera::getDirection(void) const

    {

        // Direction points down -Z by default

        return mOrientation * -Vector3::UNIT_Z;

    }

    //-----------------------------------------------------------------------

    Vector3 Camera::getUp(void) const

    {

        return mOrientation * Vector3::UNIT_Y;

    }

    //-----------------------------------------------------------------------

    Vector3 Camera::getRight(void) const

    {

        return mOrientation * Vector3::UNIT_X;

    }

    //-----------------------------------------------------------------------

    void Camera::lookAt(const Vector3& targetPoint)

    {

        updateView();

        OGRE_IGNORE_DEPRECATED_BEGIN

        this->setDirection(targetPoint - mRealPosition);

        OGRE_IGNORE_DEPRECATED_END

    }

    //-----------------------------------------------------------------------

    void Camera::lookAt( Real x, Real y, Real z )

    {

        Vector3 vTemp( x, y, z );

        OGRE_IGNORE_DEPRECATED_BEGIN

        this->lookAt(vTemp);

        OGRE_IGNORE_DEPRECATED_END

    }

    //-----------------------------------------------------------------------

    void Camera::roll(const Radian& angle)

    {

        // Rotate around local Z axis

        Vector3 zAxis = mOrientation * Vector3::UNIT_Z;

        OGRE_IGNORE_DEPRECATED_BEGIN

        rotate(zAxis, angle);

        OGRE_IGNORE_DEPRECATED_END

        invalidateView();

    }

    //-----------------------------------------------------------------------

    void Camera::yaw(const Radian& angle)

    {

        Vector3 yAxis;

        if (mYawFixed)

        {

            // Rotate around fixed yaw axis

            yAxis = mYawFixedAxis;

        }

        else

        {

            // Rotate around local Y axis

            yAxis = mOrientation * Vector3::UNIT_Y;

        }

        OGRE_IGNORE_DEPRECATED_BEGIN

        rotate(yAxis, angle);

        OGRE_IGNORE_DEPRECATED_END

        invalidateView();

    }

    //-----------------------------------------------------------------------

    void Camera::pitch(const Radian& angle)

    {

        // Rotate around local X axis

        Vector3 xAxis = mOrientation * Vector3::UNIT_X;

        OGRE_IGNORE_DEPRECATED_BEGIN

        rotate(xAxis, angle);

        OGRE_IGNORE_DEPRECATED_END

        invalidateView();

    }

    //-----------------------------------------------------------------------

    void Camera::rotate(const Vector3& axis, const Radian& angle)

    {

        Quaternion q;

        q.FromAngleAxis(angle,axis);

        OGRE_IGNORE_DEPRECATED_BEGIN

        rotate(q);

        OGRE_IGNORE_DEPRECATED_END

    }

    //-----------------------------------------------------------------------

    void Camera::rotate(const Quaternion& q)

    {

        // Note the order of the mult, i.e. q comes after

        // Normalise the quat to avoid cumulative problems with precision

        Quaternion qres = q * mOrientation;

        qres.normalise();

        mOrientation = qres;

        invalidateView();

    }

    //-----------------------------------------------------------------------

    void Camera::setFixedYawAxis(bool useFixed, const Vector3& fixedAxis)

    {

        mYawFixed = useFixed;

        mYawFixedAxis = fixedAxis;

    }

    //-----------------------------------------------------------------------

    const Quaternion& Camera::getOrientation(void) const

    {

        return mOrientation;

    }

    //-----------------------------------------------------------------------

    void Camera::_autoTrack(void)

    {

        // NB assumes that all scene nodes have been updated

        if (mAutoTrackTarget)

        {

            OGRE_IGNORE_DEPRECATED_BEGIN

            lookAt(mAutoTrackTarget->_getFullTransform() * mAutoTrackOffset);

            OGRE_IGNORE_DEPRECATED_END

        }

    }

    //-----------------------------------------------------------------------

    void Camera::setOrientation(const Quaternion& q)

    {

        mOrientation = q;

        mOrientation.normalise();

        invalidateView();

    }

    //-----------------------------------------------------------------------

    void Camera::setAutoTracking(bool enabled, SceneNode* const target,

        const Vector3& offset)

    {

        if (enabled)

        {

            assert (target != 0 && "target cannot be a null pointer if tracking is enabled");

            mAutoTrackTarget = target;

            mAutoTrackOffset = offset;

        }

        else

        {

            mAutoTrackTarget = 0;

        }

    }

    //-----------------------------------------------------------------------

    const Vector3& Camera::getPositionForViewUpdate(void) const

    {

        // Note no update, because we're calling this from the update!

        return mRealPosition;

    }

    //-----------------------------------------------------------------------

    const Quaternion& Camera::getOrientationForViewUpdate(void) const

    {

        return mRealOrientation;

    }

#endif

    //-----------------------------------------------------------------------

    bool Camera::isViewOutOfDate(void) const

    {

#ifdef OGRE_NODELESS_POSITIONING

        // Overridden from Frustum to use local orientation / position offsets

        // Attached to node?

        if (mParentNode != 0)

        {

            if (mRecalcView ||

                mParentNode->_getDerivedOrientation() != mLastParentOrientation ||

                mParentNode->_getDerivedPosition() != mLastParentPosition)

            {

                // Ok, we're out of date with SceneNode we're attached to

                mLastParentOrientation = mParentNode->_getDerivedOrientation();

                mLastParentPosition = mParentNode->_getDerivedPosition();

                mRealOrientation = mParentNode->convertLocalToWorldOrientation(mOrientation);

                mRealPosition = mParentNode->convertLocalToWorldPosition(mPosition);

                mRecalcView = true;

                mRecalcWindow = true;

            }

        }

        else

        {

            // Rely on own updates

            mRealOrientation = mOrientation;

            mRealPosition = mPosition;

        }

        // Deriving reflection from linked plane?

        if (mReflect && mLinkedReflectPlane && 

            !(mLastLinkedReflectionPlane == mLinkedReflectPlane->_getDerivedPlane()))

        {

            mReflectPlane = mLinkedReflectPlane->_getDerivedPlane();

            mReflectMatrix = Math::buildReflectionMatrix(mReflectPlane);

            mLastLinkedReflectionPlane = mLinkedReflectPlane->_getDerivedPlane();

            mRecalcView = true;

            mRecalcWindow = true;

        }

#else

        if(Frustum::isViewOutOfDate())

            mRecalcWindow = true;

#endif

        // Deriving reflected orientation / position

        if (mRecalcView)

        {

#ifndef OGRE_NODELESS_POSITIONING

            const auto& mRealOrientation = mLastParentOrientation;

            const auto& mRealPosition = mLastParentPosition;

#endif

            if (mReflect)

            {

                // Calculate reflected orientation, use up-vector as fallback axis.

                Vector3 dir = -mRealOrientation.zAxis();

                Vector3 rdir = dir.reflect(mReflectPlane.normal);

                Vector3 up = mRealOrientation.yAxis();

                mDerivedOrientation = dir.getRotationTo(rdir, up) * mRealOrientation;

                // Calculate reflected position.

                mDerivedPosition = mReflectMatrix * mRealPosition;

            }

            else

            {

                mDerivedOrientation = mRealOrientation;

                mDerivedPosition = mRealPosition;

            }

        }

        return mRecalcView;

    }

    // -------------------------------------------------------------------

    void Camera::invalidateView() const

    {

        mRecalcWindow = true;

        Frustum::invalidateView();

    }

    // -------------------------------------------------------------------

    void Camera::invalidateFrustum(void) const

    {

        mRecalcWindow = true;

        Frustum::invalidateFrustum();

    }

    //-----------------------------------------------------------------------

    void Camera::_renderScene(Viewport *vp)

    {

        OgreGpuEventScope(getName());

        //update the pixel display ratio

        if (mProjType == Ogre::PT_PERSPECTIVE)

        {

            mPixelDisplayRatio = (2 * Ogre::Math::Tan(mFOVy * 0.5f)) / vp->getActualHeight();

        }

        else

        {

            mPixelDisplayRatio = -mExtents.height() / vp->getActualHeight();

        }

        //notify prerender scene

        ListenerList listenersCopy = mListeners;

        for (auto & i : listenersCopy)

        {

            i->cameraPreRenderScene(this);

        }

        //render scene

        mManager->_renderScene(this, vp);

        // Listener list may have change

        listenersCopy = mListeners;

        //notify postrender scene

        for (auto & i : listenersCopy)

        {

            i->cameraPostRenderScene(this);

        }

    }

    //---------------------------------------------------------------------

    void Camera::addListener(Listener* l)

    {

        if (std::find(mListeners.begin(), mListeners.end(), l) == mListeners.end())

            mListeners.push_back(l);

    }

    //---------------------------------------------------------------------

    void Camera::removeListener(Listener* l)

    {

        ListenerList::iterator i = std::find(mListeners.begin(), mListeners.end(), l);

        if (i != mListeners.end())

            mListeners.erase(i);

    }

    //-----------------------------------------------------------------------

    std::ostream& operator<<( std::ostream& o, const Camera& c )

    {

        o << "Camera(Name='" << c.mName << "'";

#ifdef OGRE_NODELESS_POSITIONING

        o << ", pos=" << c.mPosition << ", direction=" << -c.mOrientation.zAxis();

#else

        o << ", pos=" << c.mLastParentPosition << ", direction=" << -c.mLastParentOrientation.zAxis();

#endif

        o << ",near=" << c.mNearDist;

        o << ", far=" << c.mFarDist << ", FOVy=" << c.mFOVy.valueDegrees();

        o << ", aspect=" << c.mAspect << ", ";

        o << ", xoffset=" << c.mFrustumOffset.x << ", yoffset=" << c.mFrustumOffset.y;

        o << ", focalLength=" << c.mFocalLength << ", ";

        o << "NearFrustumPlane=" << c.mFrustumPlanes[FRUSTUM_PLANE_NEAR] << ", ";

        o << "FarFrustumPlane=" << c.mFrustumPlanes[FRUSTUM_PLANE_FAR] << ", ";

        o << "LeftFrustumPlane=" << c.mFrustumPlanes[FRUSTUM_PLANE_LEFT] << ", ";

        o << "RightFrustumPlane=" << c.mFrustumPlanes[FRUSTUM_PLANE_RIGHT] << ", ";

        o << "TopFrustumPlane=" << c.mFrustumPlanes[FRUSTUM_PLANE_TOP] << ", ";

        o << "BottomFrustumPlane=" << c.mFrustumPlanes[FRUSTUM_PLANE_BOTTOM];

        o << ")";

        return o;

    }

    //-----------------------------------------------------------------------

    const Quaternion& Camera::getDerivedOrientation(void) const

    {

        updateView();

        return mDerivedOrientation;

    }

    //-----------------------------------------------------------------------

    const Vector3& Camera::getDerivedPosition(void) const

    {

        updateView();

        return mDerivedPosition;

    }

    //-----------------------------------------------------------------------

    Vector3 Camera::getDerivedDirection(void) const

    {

        // Direction points down -Z

        updateView();

        return -mDerivedOrientation.zAxis();

    }

    //-----------------------------------------------------------------------

    Vector3 Camera::getDerivedUp(void) const

    {

        updateView();

        return mDerivedOrientation.yAxis();

    }

    //-----------------------------------------------------------------------

    Vector3 Camera::getDerivedRight(void) const

    {

        updateView();

        return mDerivedOrientation.xAxis();

    }

    //-----------------------------------------------------------------------

    const Quaternion& Camera::getRealOrientation(void) const

    {

        updateView();

#ifdef OGRE_NODELESS_POSITIONING

        return mRealOrientation;

#else

        return mLastParentOrientation;

#endif

    }

    //-----------------------------------------------------------------------

    const Vector3& Camera::getRealPosition(void) const

    {

        updateView();

#ifdef OGRE_NODELESS_POSITIONING

        return mRealPosition;

#else

        return mLastParentPosition;

#endif

    }

    //-----------------------------------------------------------------------

    Vector3 Camera::getRealDirection(void) const

    {

        // Direction points down -Z

        updateView();

#ifdef OGRE_NODELESS_POSITIONING

        return mRealOrientation * Vector3::NEGATIVE_UNIT_Z;

#else

        return -mLastParentOrientation.zAxis();

#endif

    }

    //-----------------------------------------------------------------------

    Vector3 Camera::getRealUp(void) const

    {

        updateView();

#ifdef OGRE_NODELESS_POSITIONING

        return mRealOrientation * Vector3::UNIT_Y;

#else

        return mLastParentOrientation.yAxis();

#endif

    }

    //-----------------------------------------------------------------------

    Vector3 Camera::getRealRight(void) const

    {

        updateView();

#ifdef OGRE_NODELESS_POSITIONING

        return mRealOrientation * Vector3::UNIT_X;

#else

        return mLastParentOrientation.xAxis();

#endif

    }

    //-----------------------------------------------------------------------

    const String& Camera::getMovableType(void) const

    {

        return MOT_CAMERA;

    }

    //-----------------------------------------------------------------------

    void Camera::setLodBias(Real factor)

    {

        assert(factor > 0.0f && "Bias factor must be > 0!");

        mSceneLodFactor = factor;

        mSceneLodFactorInv = 1.0f / factor;

    }

    //-----------------------------------------------------------------------

    Real Camera::getLodBias(void) const

    {

        return mSceneLodFactor;

    }

    //-----------------------------------------------------------------------

    Real Camera::_getLodBiasInverse(void) const

    {

        return mSceneLodFactorInv;

    }

    //-----------------------------------------------------------------------

    void Camera::setLodCamera(const Camera* lodCam)

    {

        if (lodCam == this)

            mLodCamera = 0;

        else

            mLodCamera = lodCam;

    }

    //---------------------------------------------------------------------

    const Camera* Camera::getLodCamera() const

    {

        return mLodCamera? mLodCamera : this;

    }

    //-----------------------------------------------------------------------

    Ray Camera::getCameraToViewportRay(Real screenX, Real screenY) const

    {

        Ray ret;

        getCameraToViewportRay(screenX, screenY, &ret);

        return ret;

    }

    //---------------------------------------------------------------------

    void Camera::getCameraToViewportRay(Real screenX, Real screenY, Ray* outRay) const

    {

        Matrix4 inverseVP = (getProjectionMatrix() * getViewMatrix(true)).inverse();

        Real nx = (2.0f * screenX) - 1.0f;

        Real ny = 1.0f - (2.0f * screenY);

        Vector3 nearPoint(nx, ny, -1.f);

        // Use midPoint rather than far point to avoid issues with infinite projection

        Vector3 midPoint (nx, ny,  0.0f);

        // Get ray origin and ray target on near plane in world space

        Vector3 rayOrigin, rayTarget;

        rayOrigin = inverseVP * nearPoint;

        rayTarget = inverseVP * midPoint;

        Vector3 rayDirection = rayTarget - rayOrigin;

        rayDirection.normalise();

        outRay->setOrigin(rayOrigin);

        outRay->setDirection(rayDirection);

    } 

    //---------------------------------------------------------------------

    PlaneBoundedVolume Camera::getCameraToViewportBoxVolume(Real screenLeft, 

        Real screenTop, Real screenRight, Real screenBottom, bool includeFarPlane)

    {

        PlaneBoundedVolume vol;

        getCameraToViewportBoxVolume(screenLeft, screenTop, screenRight, screenBottom, 

            &vol, includeFarPlane);

        return vol;

    }

    //---------------------------------------------------------------------()

    void Camera::getCameraToViewportBoxVolume(Real screenLeft, 

        Real screenTop, Real screenRight, Real screenBottom, 

        PlaneBoundedVolume* outVolume, bool includeFarPlane)

    {

        outVolume->planes.clear();

        if (mProjType == PT_PERSPECTIVE)

        {

            // Use the corner rays to generate planes

            Ray ul = getCameraToViewportRay(screenLeft, screenTop);

            Ray ur = getCameraToViewportRay(screenRight, screenTop);

            Ray bl = getCameraToViewportRay(screenLeft, screenBottom);

            Ray br = getCameraToViewportRay(screenRight, screenBottom);

            Vector3 normal;

            // top plane

            normal = ul.getDirection().crossProduct(ur.getDirection());

            normal.normalise();

            outVolume->planes.push_back(

                Plane(normal, getDerivedPosition()));

            // right plane

            normal = ur.getDirection().crossProduct(br.getDirection());

            normal.normalise();

            outVolume->planes.push_back(

                Plane(normal, getDerivedPosition()));

            // bottom plane

            normal = br.getDirection().crossProduct(bl.getDirection());

            normal.normalise();

            outVolume->planes.push_back(

                Plane(normal, getDerivedPosition()));

            // left plane

            normal = bl.getDirection().crossProduct(ul.getDirection());

            normal.normalise();

            outVolume->planes.push_back(

                Plane(normal, getDerivedPosition()));

        }

        else

        {

            // ortho planes are parallel to frustum planes

            Ray ul = getCameraToViewportRay(screenLeft, screenTop);

            Ray br = getCameraToViewportRay(screenRight, screenBottom);

            updateFrustumPlanes();

            outVolume->planes.push_back(

                Plane(mFrustumPlanes[FRUSTUM_PLANE_TOP].normal, ul.getOrigin()));

            outVolume->planes.push_back(

                Plane(mFrustumPlanes[FRUSTUM_PLANE_RIGHT].normal, br.getOrigin()));

            outVolume->planes.push_back(

                Plane(mFrustumPlanes[FRUSTUM_PLANE_BOTTOM].normal, br.getOrigin()));

            outVolume->planes.push_back(

                Plane(mFrustumPlanes[FRUSTUM_PLANE_LEFT].normal, ul.getOrigin()));

        }

        // near & far plane applicable to both projection types

        outVolume->planes.push_back(getFrustumPlane(FRUSTUM_PLANE_NEAR));

        if (includeFarPlane)

            outVolume->planes.push_back(getFrustumPlane(FRUSTUM_PLANE_FAR));

    }

    // -------------------------------------------------------------------

    void Camera::setWindow (Real Left, Real Top, Real Right, Real Bottom)

    {

        mWLeft = Left;

        mWTop = Top;

        mWRight = Right;

        mWBottom = Bottom;

        mWindowSet = true;

        mRecalcWindow = true;

    }

    // -------------------------------------------------------------------

    void Camera::resetWindow ()

    {

        mWindowSet = false;

    }

    // -------------------------------------------------------------------

    void Camera::setWindowImpl() const

    {

        if (!mWindowSet || !mRecalcWindow)

            return;

        // Calculate general projection parameters

        RealRect vp = calcProjectionParameters();

        Real vpWidth = vp.width();

        Real vpHeight = -vp.height();

        Real wvpLeft   = vp.left + mWLeft * vpWidth;

        Real wvpRight  = vp.left + mWRight * vpWidth;

        Real wvpTop    = vp.top - mWTop * vpHeight;

        Real wvpBottom = vp.top - mWBottom * vpHeight;

        Vector3 vp_ul (wvpLeft, wvpTop, -mNearDist);

        Vector3 vp_ur (wvpRight, wvpTop, -mNearDist);

        Vector3 vp_bl (wvpLeft, wvpBottom, -mNearDist);

        Vector3 vp_br (wvpRight, wvpBottom, -mNearDist);

        Affine3 inv = mViewMatrix.inverse();

        Vector3 vw_ul = inv * vp_ul;

        Vector3 vw_ur = inv * vp_ur;

        Vector3 vw_bl = inv * vp_bl;

        Vector3 vw_br = inv * vp_br;

        mWindowClipPlanes.clear();

        if (mProjType == PT_PERSPECTIVE)

        {

            Vector3 position = getPositionForViewUpdate();

            mWindowClipPlanes.push_back(Plane(position, vw_bl, vw_ul));

            mWindowClipPlanes.push_back(Plane(position, vw_ul, vw_ur));

            mWindowClipPlanes.push_back(Plane(position, vw_ur, vw_br));

            mWindowClipPlanes.push_back(Plane(position, vw_br, vw_bl));

        }

        else

        {

            Vector3 x_axis(inv[0][0], inv[0][1], inv[0][2]);

            Vector3 y_axis(inv[1][0], inv[1][1], inv[1][2]);

            x_axis.normalise();

            y_axis.normalise();

            mWindowClipPlanes.push_back(Plane( x_axis, vw_bl));

            mWindowClipPlanes.push_back(Plane(-x_axis, vw_ur));

            mWindowClipPlanes.push_back(Plane( y_axis, vw_bl));

            mWindowClipPlanes.push_back(Plane(-y_axis, vw_ur));

        }

        mRecalcWindow = false;

    }

    // -------------------------------------------------------------------

    const std::vector<Plane>& Camera::getWindowPlanes(void) const

    {

        updateView();

        setWindowImpl();

        return mWindowClipPlanes;

    }

    // -------------------------------------------------------------------

    Real Camera::getBoundingRadius(void) const

    {

        // return a little bigger than the near distance

        // just to keep things just outside

        return mNearDist * 1.5f;

    }

    //-----------------------------------------------------------------------

    bool Camera::getAutoAspectRatio(void) const

    {

        return mAutoAspectRatio;

    }

    //-----------------------------------------------------------------------

    void Camera::setAutoAspectRatio(bool autoratio)

    {

        mAutoAspectRatio = autoratio;

    }

    //-----------------------------------------------------------------------

    bool Camera::isVisible(const AxisAlignedBox& bound, FrustumPlane* culledBy) const

    {

        if (mCullFrustum)

        {

            return mCullFrustum->isVisible(bound, culledBy);

        }

        else

        {

            return Frustum::isVisible(bound, culledBy);

        }

    }

    //-----------------------------------------------------------------------

    bool Camera::isVisible(const Sphere& bound, FrustumPlane* culledBy) const

    {

        if (mCullFrustum)

        {

            return mCullFrustum->isVisible(bound, culledBy);

        }

        else

        {

            return Frustum::isVisible(bound, culledBy);

        }

    }

    //-----------------------------------------------------------------------

    bool Camera::isVisible(const Vector3& vert, FrustumPlane* culledBy) const

    {

        if (mCullFrustum)

        {

            return mCullFrustum->isVisible(vert, culledBy);

        }

        else

        {

            return Frustum::isVisible(vert, culledBy);

        }

    }

    //-----------------------------------------------------------------------

    const Frustum::Corners& Camera::getWorldSpaceCorners(void) const

    {

        if (mCullFrustum)

        {

            return mCullFrustum->getWorldSpaceCorners();

        }

        else

        {

            return Frustum::getWorldSpaceCorners();

        }

    }

    //-----------------------------------------------------------------------

    const Plane& Camera::getFrustumPlane( unsigned short plane ) const

    {

        if (mCullFrustum)

        {

            return mCullFrustum->getFrustumPlane(plane);

        }

        else

        {

            return Frustum::getFrustumPlane(plane);

        }

    }

    //-----------------------------------------------------------------------

    bool Camera::projectSphere(const Sphere& sphere, 

        Real* left, Real* top, Real* right, Real* bottom) const

    {

        if (mCullFrustum)

        {

            return mCullFrustum->projectSphere(sphere, left, top, right, bottom);

        }

        else

        {

            return Frustum::projectSphere(sphere, left, top, right, bottom);

        }

    }

    //-----------------------------------------------------------------------

    float Camera::getNearClipDistance(void) const

    {

        if (mCullFrustum)

        {

            return mCullFrustum->getNearClipDistance();

        }

        else

        {

            return Frustum::getNearClipDistance();

        }

    }

    //-----------------------------------------------------------------------

    float Camera::getFarClipDistance(void) const

    {

        if (mCullFrustum)

        {

            return mCullFrustum->getFarClipDistance();

        }

        else

        {

            return Frustum::getFarClipDistance();

        }

    }

    //-----------------------------------------------------------------------

    const Affine3& Camera::getViewMatrix(void) const

    {

        if (mCullFrustum)

        {

            return mCullFrustum->getViewMatrix();

        }

        else

        {

            return Frustum::getViewMatrix();

        }

    }

    //-----------------------------------------------------------------------

    const Affine3& Camera::getViewMatrix(bool ownFrustumOnly) const

    {

        if (ownFrustumOnly)

        {

            return Frustum::getViewMatrix();

        }

        else

        {

            return getViewMatrix();

        }

    }

    //-----------------------------------------------------------------------

    //_______________________________________________________

    //|                                                     |

    //| getRayForwardIntersect                              |

    //| -----------------------------                       |

    //| get the intersections of frustum rays with a plane  |

    //| of interest.  The plane is assumed to have constant |

    //| z.  If this is not the case, rays                   |

    //| should be rotated beforehand to work in a           |

    //| coordinate system in which this is true.            |

    //|_____________________________________________________|

    //