//C++ header - Open Scene Graph - Copyright (C) 1998-2002 Robert Osfield //Distributed under the terms of the GNU Library General Public License (LGPL) //as published by the Free Software Foundation. #ifndef OSG_ImpostorSprite #define OSG_ImpostorSprite 1 #include #include #include #include #include #include namespace osg { class Texture2D; class Impostor; class ImpostorSpriteManager; /** An ImposterSprite is a textured quad which is rendered in place a * 3D geometry. The ImposterSprite is generated by rendering the original * 3D geometry to a texture as an image cache. The ImpostorSprite is * automatically generated by the osgUtil::CullVisitor so it not * necessary to deal with it directly. */ class SG_EXPORT ImpostorSprite : public Drawable { public: ImpostorSprite(); /** Clone an object of the same type as an ImpostorSprite.*/ virtual Object* cloneType() const { return osgNew ImpostorSprite(); } /** Clone on ImpostorSprite just returns a clone of type, * since it is not appropriate to share data of an ImpostorSprite.*/ virtual Object* clone(const CopyOp&) const { return osgNew ImpostorSprite(); } virtual bool isSameKindAs(const Object* obj) const { return dynamic_cast(obj)!=NULL; } virtual const char* libraryName() const { return "osg"; } virtual const char* className() const { return "ImpostorSprite"; } /** Set the parent, which must be an Impostor. * Unlike conventional Drawables, ImpostorSprite's can only ever have * one parent. */ void setParent(Impostor* parent) { _parent = parent; } /** Get the parent, which is an Impostor. */ Impostor* getParent() { return _parent; } /** Get the const parent, which is an Impostor. */ const Impostor* getParent() const { return _parent; } /** Set the eye point for when the ImpsotorSprite was snapped.*/ inline void setStoredLocalEyePoint(const Vec3& v) { _storedLocalEyePoint=v; } /** Get the eye point for when the ImpsotorSprite was snapped.*/ inline const Vec3& getStoredLocalEyePoint() const { return _storedLocalEyePoint; } /** Set the frame number for when the ImpostorSprite was last used in rendering.*/ inline void setLastFrameUsed(const int frameNumber) { _lastFrameUsed = frameNumber; } /** Get the frame number for when the ImpostorSprite was last used in rendering.*/ inline int getLastFrameUsed() const { return _lastFrameUsed; } /** Get the coordinates of the corners of the quad. * Stored in the order, [0] - top_left, [1] - bottom_left, [2] - bottom_right, [3] - top_left. */ inline Vec3* getCoords() { return _coords; } /** Get the const coordinates of the corners of the quad. */ inline const Vec3* getCoords() const { return _coords; } /** Get the texture coordinates of the corners of the quad. * Stored in the order, [0] - top_left, [1] - bottom_left, [2] - bottom_right, [3] - top_left. */ inline Vec2* getTexCoords() { return _texcoords; } /** Get the const texture coordinates of the corners of the quad.*/ inline const Vec2* getTexCoords() const { return _texcoords; } /** Get the control coordinates of the corners of the quad. * The control coordinates are the corners of the quad projected * out onto the front face of bounding box which enclosed the impostor * geometry when it was pre-rendered into the impostor sprite's texture. * At the point of creation/or update of the impostor sprite the control * coords will lie on top of the corners of the quad in screen space - with a pixel error * or zero. Once the camera moves relative to the impostor sprite the * control coords will no longer lie on top of the corners of the quad in * screen space - a pixel error will have accumulated. This pixel error * can then be used to determine whether the impostor needs to be updated. * Stored in the order, [0] - top_left, [1] - bottom_left, [2] - bottom_right, [3] - top_left. */ inline Vec3* getControlCoords() { return _controlcoords; } /** Get the const control coordinates of the corners of the quad.*/ inline const Vec3* getControlCoords() const { return _controlcoords; } /** calculate the pixel error value for passing in the ModelViewProjectionWindow transform, * which transform local coords into screen space.*/ const float calcPixelError(const Matrix& MVPW) const; void setTexture(Texture2D* tex,int s,int t); Texture2D* getTexture() { return _texture; } const Texture2D* getTexture() const { return _texture; } const int s() const { return _s; } const int t() const { return _t; } /** draw ImpostorSprite directly. */ virtual void drawImmediateMode(State& state); /** accept an AttributeFunctor and call its methods to tell it about the interal attributes that this Drawable has.*/ virtual void accept(AttributeFunctor& af); /** accept a PrimtiveFunctor and call its methods to tell it about the interal primtives that this Drawable has.*/ virtual void accept(PrimitiveFunctor& pf); protected: ImpostorSprite(const ImpostorSprite&):Drawable() {} ImpostorSprite& operator = (const ImpostorSprite&) { return *this;} virtual ~ImpostorSprite(); virtual const bool computeBound() const; Impostor* _parent; friend class osg::ImpostorSpriteManager; // support for a double linked list managed by the // ImposotorSpriteManager. ImpostorSpriteManager* _ism; ImpostorSprite* _previous; ImpostorSprite* _next; int _lastFrameUsed; Vec3 _storedLocalEyePoint; Vec3 _coords[4]; Vec2 _texcoords[4]; Vec3 _controlcoords[4]; Texture2D* _texture; int _s; int _t; }; /** Helper class for managing the reuse of ImpostorSprite resources.*/ class SG_EXPORT ImpostorSpriteManager : public Referenced { public: ImpostorSpriteManager(); const bool empty() const { return _first==0; } ImpostorSprite* first() { return _first; } ImpostorSprite* last() { return _last; } void push_back(ImpostorSprite* is); void remove(ImpostorSprite* is); ImpostorSprite* createOrReuseImpostorSprite(int s,int t,int frameNumber); protected: ~ImpostorSpriteManager(); ref_ptr _texenv; ref_ptr _alphafunc; ImpostorSprite* _first; ImpostorSprite* _last; }; } #endif