source: GTP/trunk/App/Demos/Vis/FriendlyCulling/src/Camera.h @ 2911

#ifndef __CAMERA_H
#define __CAMERA_H

#include "Vector3.h"
#include "AxisAlignedBox3.h"
#include "Plane3.h"


namespace CHCDemoEngine 
{

class Matrix4x4;
class Polyhedron;

/** Class representing a frustum.
*/
class Frustum
{
        friend class Camera;

public:

        Frustum() {};

        Frustum(const Matrix4x4 &trafo);

        enum { RIGHT_PLANE, LEFT_PLANE, BOTTOM_PLANE, TOP_PLANE, FAR_PLANE, NEAR_PLANE};
        /** Resizes the current frustum so that it fully encloses the given polyhedron
        */
        void EnclosePolyhedron(const Polyhedron &polyhedron);

        void ExtractTransformation(Matrix4x4 &m) const;


        /// the 6 clip planes
        Plane3 mClipPlanes[6];
};


class Camera
{
public:
        
        Camera();

        Camera(int width, int height, float fieldOfView = 90.f);


        void SetPosition(const Vector3 &pos);

        inline Vector3 GetPosition() const { return mPosition; }
        
        Vector3 GetDirection() const;
        Vector3 GetUpVector() const;
        Vector3 GetRightVector() const;

        Vector3 GetBaseDirection() const;
        Vector3 GetBaseUpVector() const;
        Vector3 GetBaseRightVector() const;

        inline float GetFov() const { return mFovy; }
        inline float GetAspect() const { return (float) mWidth / mHeight; }
        inline int GetWidth() const { return mWidth; }
        inline int GetHeight() const { return mHeight; }

        /** Sets up viewing in gl
        */
        void SetupCameraView();
        /** Returns the current projection matrix.
        */
        void GetProjectionMatrix(Matrix4x4 &mat);
        /** Returns the current model view matrix.
        */
        void GetModelViewMatrix(Matrix4x4 &mat);
        /** Calculates a frustum from the projection and the modelview matrix.
        */
        void CalcFrustum(Frustum &frustum);
        /** Computes the extremal points of this frustum.
        */
        void ComputePoints(Vector3 &ftl, Vector3 &ftr, Vector3 &fbl, Vector3 &fbr,
                               Vector3 &ntl, Vector3 &ntr, Vector3 &nbl, Vector3 &nbr) const;
        /** Computes the extremal points of the base frustum.
        */
        void ComputeBasePoints(Vector3 &ftl, Vector3 &ftr, Vector3 &fbl, Vector3 &fbr,
                                                   Vector3 &ntl, Vector3 &ntr, Vector3 &nbl, Vector3 &nbr) const;
        /** Returns the near plane.
        */
        inline float GetNear() const { return mNear; }
        /** Returns the far plane.
        */
        inline float GetFar() const { return mFar; }
        /** Sets the near plane
        */
        void SetNear(float nearDist);
        /** Sets the far plane.
        */
        void SetFar(float farDist);
        
        void SetOrtho(bool ortho);

        void Yaw(float angle);
        void Pitch(float angle);
        
        float GetPitch() const { return mPitch; }
        float GetYaw() const { return mYaw; }
        void ResetPitchAndYaw() { mPitch = 0; mYaw = 0; }
        /** Sets the camera direction.
        */
        void SetDirection(const Vector3 &direction);

        /** Calculates the intersection of the frustum with the box,
                returns resultin polyhedron as array of polygons.
        */
        Polyhedron *CalcClippedFrustum(const AxisAlignedBox3 &box) const;


protected:

        void Precompute(const Vector3 &direction);

        void CalculateFromPitchAndYaw();

        void ComputePointsInternal(Vector3 &ftl, Vector3 &ftr, Vector3 &fbl, Vector3 &fbr,
                                                           Vector3 &ntl, Vector3 &ntr, Vector3 &nbl, Vector3 &nbr,
                                                           const Vector3 &view, const Vector3 &right, const Vector3 &up,
                                                           const Vector3 &pos) const;

        ////////////////
        //-- members

        float mFovy;
        int mWidth;
        int mHeight;

        float mNear;

        float mFar;

        bool mIsOrtho;

        Matrix4x4 mBaseOrientation;
        Matrix4x4 mViewOrientation;

        float mPitch;
        float mYaw;

        Vector3 mPosition;
};

}
#endif