/*

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

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.

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

*/

#ifndef __Compositor_H__

#define __Compositor_H__

#include "OgrePrerequisites.h"

#include "OgreHeaderPrefix.h"

namespace Ogre {

    template <typename T> class VectorIterator;

    /** \addtogroup Core

    *  @{

    */

    /** \addtogroup Effects

    *  @{

    */

    /** Class representing a Compositor object. Compositors provide the means 

        to flexibly "composite" the final rendering result from multiple scene renders

        and intermediate operations like rendering fullscreen quads. This makes 

        it possible to apply postfilter effects, HDRI postprocessing, and shadow 

        effects to a Viewport.

     */

    class _OgreExport Compositor final : public Resource

    {

    public:

        Compositor(ResourceManager* creator, const String& name, ResourceHandle handle,

            const String& group, bool isManual = false, ManualResourceLoader* loader = 0);

        ~Compositor();

        /// Data types for internal lists

        typedef std::vector<CompositionTechnique *> Techniques;

        typedef VectorIterator<Techniques> TechniqueIterator;

        /** Create a new technique, and return a pointer to it.

        */

        CompositionTechnique *createTechnique();

        /** Remove a technique. It will also be destroyed.

        */

        void removeTechnique(size_t idx);

        /** Get a technique.

        */

        CompositionTechnique *getTechnique(size_t idx) const { return mTechniques.at(idx); }

        /** Get the number of techniques.

        */

        size_t getNumTechniques() const { return mTechniques.size(); }

        /** Remove all techniques

        */

        void removeAllTechniques();

        /** Get an iterator over the Techniques in this compositor. */

        TechniqueIterator getTechniqueIterator(void);

        /** Get a supported technique.

            The supported technique list is only available after this compositor has been compiled,

            which typically happens on loading it. Therefore, if this method returns

            an empty list, try calling Compositor::load.

        */

        CompositionTechnique *getSupportedTechnique(size_t idx) const { return mSupportedTechniques.at(idx); }

        /** Get the number of supported techniques.

            The supported technique list is only available after this compositor has been compiled,

            which typically happens on loading it. Therefore, if this method returns

            an empty list, try calling Compositor::load.

        */

        size_t getNumSupportedTechniques() const { return mSupportedTechniques.size(); }

        /** Gets an iterator over all the Techniques which are supported by the current card. 

            The supported technique list is only available after this compositor has been compiled,

            which typically happens on loading it. Therefore, if this method returns

            an empty list, try calling Compositor::load.

        */

        TechniqueIterator getSupportedTechniqueIterator(void);

        /** Get a pointer to a supported technique for a given scheme. 

            If there is no specific supported technique with this scheme name, 

            then the first supported technique with no specific scheme will be returned.

        @param schemeName The scheme name you are looking for. Blank means to 

            look for techniques with no scheme associated

        */

        CompositionTechnique *getSupportedTechnique(const String& schemeName = BLANKSTRING);

        /** Get the instance name for a global texture.

        @param name The name of the texture in the original compositor definition

        @param mrtIndex If name identifies a MRT, which texture attachment to retrieve

        @return The instance name for the texture, corresponds to a real texture

        */

        const String& getTextureInstanceName(const String& name, size_t mrtIndex);

        /** Get the instance of a global texture.

        @param name The name of the texture in the original compositor definition

        @param mrtIndex If name identifies a MRT, which texture attachment to retrieve

        @return The texture pointer, corresponds to a real texture

        */

        const TexturePtr& getTextureInstance(const String& name, size_t mrtIndex);

        /** Get the render target for a given render texture name. 

            You can use this to add listeners etc, but do not use it to update the

            targets manually or any other modifications, the compositor instance 

            is in charge of this.

        */

        RenderTarget* getRenderTarget(const String& name, int slice = 0);

    protected:

        /// @copydoc Resource::loadImpl

        void loadImpl(void) override;

        /// @copydoc Resource::unloadImpl

        void unloadImpl(void) override;

        /// @copydoc Resource::calculateSize

        size_t calculateSize(void) const override;

        /** Check supportedness of techniques.

         */

        void compile();

    private:

        Techniques mTechniques;

        Techniques mSupportedTechniques;

        /// Compilation required

        /// This is set if the techniques change and the supportedness of techniques has to be

        /// re-evaluated.

        bool mCompilationRequired;

        /** Create global rendertextures.

        */

        void createGlobalTextures();

        /** Destroy global rendertextures.

        */

        void freeGlobalTextures();

        //TODO GSOC : These typedefs are duplicated from CompositorInstance. Solve?

        /// Map from name->local texture

        typedef std::unordered_map<String,TexturePtr> GlobalTextureMap;

        GlobalTextureMap mGlobalTextures;

        /// Store a list of MRTs we've created

        typedef std::unordered_map<String,MultiRenderTarget*> GlobalMRTMap;

        GlobalMRTMap mGlobalMRTs;

    };

    /** @} */

    /** @} */

}

#include "OgreHeaderSuffix.h"

#endif