source: downloads/ogre/OgreMain/src/OgreCompositorChain.cpp @ 50

/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2006 Torus Knot Software Ltd
Also see acknowledgements in Readme.html

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place - Suite 330, Boston, MA 02111-1307, USA, or go to
http://www.gnu.org/copyleft/lesser.txt.

You may alternatively use this source under the terms of a specific version of
the OGRE Unrestricted License provided you have obtained such a license from
Torus Knot Software Ltd.
-----------------------------------------------------------------------------
*/
#include "OgreStableHeaders.h"
#include "OgreCompositorChain.h"
#include "OgreCompositionTechnique.h"
#include "OgreCompositorInstance.h"
#include "OgreCompositionTargetPass.h"
#include "OgreCompositionPass.h"
#include "OgreViewport.h"
#include "OgreCamera.h"
#include "OgreRenderTarget.h"
#include "OgreLogManager.h"
#include "OgreCompositorManager.h"
#include "OgreSceneManager.h"
#include "OgreRenderQueueInvocation.h"
namespace Ogre {
CompositorChain::CompositorChain(Viewport *vp):
    mViewport(vp),
        mOriginalScene(0),
    mDirty(true),
        mAnyCompositorsEnabled(false)
{
        mOldClearEveryFrameBuffers = mViewport->getClearBuffers();
    assert(mViewport);
}
//-----------------------------------------------------------------------
CompositorChain::~CompositorChain()
{
        destroyResources();
}
//-----------------------------------------------------------------------
void CompositorChain::destroyResources(void)
{
        clearCompiledState();

        if (mViewport)
        {
                removeAllCompositors();
                mViewport->getTarget()->removeListener(this);
                /// Destroy "original scene" compositor instance
                if (mOriginalScene)
                {
                        mOriginalScene->getTechnique()->destroyInstance(mOriginalScene);
                        mOriginalScene = 0;
                }
                mViewport = 0;
        }
}
//-----------------------------------------------------------------------
CompositorInstance* CompositorChain::addCompositor(CompositorPtr filter, size_t addPosition, size_t technique)
{
        // Init on demand
        if (!mOriginalScene)
        {
                mViewport->getTarget()->addListener(this);
                
                /// Create base "original scene" compositor
                CompositorPtr base = CompositorManager::getSingleton().load("Ogre/Scene",
                        ResourceGroupManager::INTERNAL_RESOURCE_GROUP_NAME);
                mOriginalScene = base->getSupportedTechnique(0)->createInstance(this);
        }


        filter->touch();
    if(technique >= filter->getNumSupportedTechniques())
    {
        /// Warn user
        LogManager::getSingleton().logMessage(
            "CompositorChain: Compositor " + filter->getName() + " has no supported techniques.", LML_CRITICAL
        );
        return 0;
    }
    CompositionTechnique *tech = filter->getSupportedTechnique(technique);
    CompositorInstance *t = tech->createInstance(this);
    
    if(addPosition == LAST)
        addPosition = mInstances.size();
    else
        assert(addPosition <= mInstances.size() && "Index out of bounds.");
    mInstances.insert(mInstances.begin()+addPosition, t);
    
    mDirty = true;
        mAnyCompositorsEnabled = true;
    return t;
}
//-----------------------------------------------------------------------
void CompositorChain::removeCompositor(size_t index)
{
    assert (index < mInstances.size() && "Index out of bounds.");
    Instances::iterator i = mInstances.begin() + index;
    (*i)->getTechnique()->destroyInstance(*i);
    mInstances.erase(i);
    
    mDirty = true;
}
//-----------------------------------------------------------------------
size_t CompositorChain::getNumCompositors()
{
    return mInstances.size();
}
//-----------------------------------------------------------------------
void CompositorChain::removeAllCompositors()
{
    Instances::iterator i, iend;
    iend = mInstances.end();
    for (i = mInstances.begin(); i != iend; ++i)
    {
        (*i)->getTechnique()->destroyInstance(*i);
    }
    mInstances.clear();
    
    mDirty = true;
}
//-----------------------------------------------------------------------
void CompositorChain::_removeInstance(CompositorInstance *i)
{
        mInstances.erase(std::find(mInstances.begin(), mInstances.end(), i));
        i->getTechnique()->destroyInstance(i);
}
//-----------------------------------------------------------------------
void CompositorChain::_queuedOperation(CompositorInstance::RenderSystemOperation* op)
{
        mRenderSystemOperations.push_back(op);

}
//-----------------------------------------------------------------------
CompositorInstance *CompositorChain::getCompositor(size_t index)
{
    assert (index < mInstances.size() && "Index out of bounds.");
    return mInstances[index];
}

//-----------------------------------------------------------------------
CompositorChain::InstanceIterator CompositorChain::getCompositors()
{
    return InstanceIterator(mInstances.begin(), mInstances.end());
}
//-----------------------------------------------------------------------
void CompositorChain::setCompositorEnabled(size_t position, bool state)
{
    getCompositor(position)->setEnabled(state);
}
//-----------------------------------------------------------------------
void CompositorChain::preRenderTargetUpdate(const RenderTargetEvent& evt)
{
        /// Compile if state is dirty
        if(mDirty)
                _compile();

        // Do nothing if no compositors enabled
        if (!mAnyCompositorsEnabled)
        {
                return;
        }


        /// Update dependent render targets; this is done in the preRenderTarget 
        /// and not the preViewportUpdate for a reason: at this time, the
        /// target Rendertarget will not yet have been set as current. 
        /// ( RenderSystem::setViewport(...) ) if it would have been, the rendering
        /// order would be screwed up and problems would arise with copying rendertextures.
    Camera *cam = mViewport->getCamera();
    /// Iterate over compiled state
    CompositorInstance::CompiledState::iterator i;
    for(i=mCompiledState.begin(); i!=mCompiledState.end(); ++i)
    {
                /// Skip if this is a target that should only be initialised initially
                if(i->onlyInitial && i->hasBeenRendered)
                        continue;
                i->hasBeenRendered = true;
                /// Setup and render
        preTargetOperation(*i, i->target->getViewport(0), cam);
        i->target->update();
        postTargetOperation(*i, i->target->getViewport(0), cam);
    }
}
//-----------------------------------------------------------------------
void CompositorChain::preViewportUpdate(const RenderTargetViewportEvent& evt)
{
        // Only set up if there is at least one compositor enabled, and it's this viewport
    if(evt.source != mViewport || !mAnyCompositorsEnabled)
        return;

        // set original scene details from viewport
        CompositionPass* pass = mOriginalScene->getTechnique()->getOutputTargetPass()->getPass(0);
        CompositionTargetPass* passParent = pass->getParent();
        if (pass->getClearBuffers() != mViewport->getClearBuffers() ||
                pass->getClearColour() != mViewport->getBackgroundColour() ||
                passParent->getVisibilityMask() != mViewport->getVisibilityMask() ||
                passParent->getMaterialScheme() != mViewport->getMaterialScheme() ||
                passParent->getShadowsEnabled() != mViewport->getShadowsEnabled())
        {
                // recompile if viewport settings are different
                pass->setClearBuffers(mViewport->getClearBuffers());
                pass->setClearColour(mViewport->getBackgroundColour());
                passParent->setVisibilityMask(mViewport->getVisibilityMask());
                passParent->setMaterialScheme(mViewport->getMaterialScheme());
                passParent->setShadowsEnabled(mViewport->getShadowsEnabled());
                _compile();
        }

        Camera *cam = mViewport->getCamera();
        /// Prepare for output operation
        preTargetOperation(mOutputOperation, mViewport, cam);
}
//-----------------------------------------------------------------------
void CompositorChain::preTargetOperation(CompositorInstance::TargetOperation &op, Viewport *vp, Camera *cam)
{
    SceneManager *sm = cam->getSceneManager();
        /// Set up render target listener
        mOurListener.setOperation(&op, sm, sm->getDestinationRenderSystem());
        mOurListener.notifyViewport(vp);
        /// Register it
        sm->addRenderQueueListener(&mOurListener);
        /// Set visiblity mask
        mOldVisibilityMask = sm->getVisibilityMask();
        sm->setVisibilityMask(op.visibilityMask);
        /// Set whether we find visibles
        mOldFindVisibleObjects = sm->getFindVisibleObjects();
        sm->setFindVisibleObjects(op.findVisibleObjects);
    /// Set LOD bias level
    mOldLodBias = cam->getLodBias();
    cam->setLodBias(cam->getLodBias() * op.lodBias);
        /// Set material scheme 
        mOldMaterialScheme = vp->getMaterialScheme();
        vp->setMaterialScheme(op.materialScheme);
        /// Set shadows enabled
        mOldShadowsEnabled = vp->getShadowsEnabled();
        vp->setShadowsEnabled(op.shadowsEnabled);
    /// XXX TODO
    //vp->setClearEveryFrame( true );
    //vp->setOverlaysEnabled( false );
    //vp->setBackgroundColour( op.clearColour );
}
//-----------------------------------------------------------------------
void CompositorChain::postTargetOperation(CompositorInstance::TargetOperation &op, Viewport *vp, Camera *cam)
{
    SceneManager *sm = cam->getSceneManager();
        /// Unregister our listener
        sm->removeRenderQueueListener(&mOurListener);
        /// Flush remaing operations
        mOurListener.flushUpTo((uint8)RENDER_QUEUE_COUNT);
        /// Restore default scene and camera settings
        sm->setVisibilityMask(mOldVisibilityMask);
        sm->setFindVisibleObjects(mOldFindVisibleObjects);
    cam->setLodBias(mOldLodBias);
        vp->setMaterialScheme(mOldMaterialScheme);
        vp->setShadowsEnabled(mOldShadowsEnabled);
}
//-----------------------------------------------------------------------
void CompositorChain::postViewportUpdate(const RenderTargetViewportEvent& evt)
{
        // Only tidy up if there is at least one compositor enabled, and it's this viewport
    if(evt.source != mViewport || !mAnyCompositorsEnabled)
        return;

        postTargetOperation(mOutputOperation, mViewport, mViewport->getCamera());
}
//-----------------------------------------------------------------------
void CompositorChain::viewportRemoved(const RenderTargetViewportEvent& evt)
{
        // this chain is now orphaned
        // can't delete it since held from outside, but release all resources being used
        destroyResources();

}
//-----------------------------------------------------------------------
void CompositorChain::clearCompiledState()
{
        for (RenderSystemOperations::iterator i = mRenderSystemOperations.begin();
                i != mRenderSystemOperations.end(); ++i)
        {
                delete *i;
        }
        mRenderSystemOperations.clear();

        /// Clear compiled state
        mCompiledState.clear();
        mOutputOperation = CompositorInstance::TargetOperation(0);

}
//-----------------------------------------------------------------------
void CompositorChain::_compile()
{
        clearCompiledState();

        bool compositorsEnabled = false;

    /// Set previous CompositorInstance for each compositor in the list
    CompositorInstance *lastComposition = mOriginalScene;
        mOriginalScene->mPreviousInstance = 0;
        CompositionPass* pass = mOriginalScene->getTechnique()->getOutputTargetPass()->getPass(0);
        pass->setClearBuffers(mViewport->getClearBuffers());
        pass->setClearColour(mViewport->getBackgroundColour());
    for(Instances::iterator i=mInstances.begin(); i!=mInstances.end(); ++i)
    {
        if((*i)->getEnabled())
        {
                        compositorsEnabled = true;
            (*i)->mPreviousInstance = lastComposition;
            lastComposition = (*i);
        }
    }
    

    /// Compile misc targets
    lastComposition->_compileTargetOperations(mCompiledState);
    
    /// Final target viewport (0)
        mOutputOperation.renderSystemOperations.clear();
    lastComposition->_compileOutputOperation(mOutputOperation);

        // Deal with viewport settings
        if (compositorsEnabled != mAnyCompositorsEnabled)
        {
                mAnyCompositorsEnabled = compositorsEnabled;
                if (mAnyCompositorsEnabled)
                {
                        // Save old viewport clearing options
                        mOldClearEveryFrameBuffers = mViewport->getClearBuffers();
                        // Don't clear anything every frame since we have our own clear ops
                        mViewport->setClearEveryFrame(false);
                }
                else
                {
                        // Reset clearing options
                        mViewport->setClearEveryFrame(mOldClearEveryFrameBuffers > 0, 
                                mOldClearEveryFrameBuffers);
                }
        }
    
    mDirty = false;
}
//-----------------------------------------------------------------------
void CompositorChain::_markDirty()
{
    mDirty = true;
}
//-----------------------------------------------------------------------
Viewport *CompositorChain::getViewport()
{
    return mViewport;
}
//-----------------------------------------------------------------------
void CompositorChain::RQListener::renderQueueStarted(uint8 id, 
        const String& invocation, bool& skipThisQueue)
{
        // Skip when not matching viewport
        // shadows update is nested within main viewport update
        if (mSceneManager->getCurrentViewport() != mViewport)
                return;

        flushUpTo(id);
        /// If noone wants to render this queue, skip it
        /// Don't skip the OVERLAY queue because that's handled seperately
        if(!mOperation->renderQueues.test(id) && id!=RENDER_QUEUE_OVERLAY)
        {
                skipThisQueue = true;
        }
}
//-----------------------------------------------------------------------
void CompositorChain::RQListener::renderQueueEnded(uint8 id, 
        const String& invocation, bool& repeatThisQueue)
{
}
//-----------------------------------------------------------------------
void CompositorChain::RQListener::setOperation(CompositorInstance::TargetOperation *op,SceneManager *sm,RenderSystem *rs)
{
        mOperation = op;
        mSceneManager = sm;
        mRenderSystem = rs;
        currentOp = op->renderSystemOperations.begin();
        lastOp = op->renderSystemOperations.end();
}
//-----------------------------------------------------------------------
void CompositorChain::RQListener::flushUpTo(uint8 id)
{
        /// Process all RenderSystemOperations up to and including render queue id.
    /// Including, because the operations for RenderQueueGroup x should be executed
        /// at the beginning of the RenderQueueGroup render for x.
        while(currentOp != lastOp && currentOp->first <= id)
        {
                currentOp->second->execute(mSceneManager, mRenderSystem);
                ++currentOp;
        }
}
//-----------------------------------------------------------------------
}