/* NODEOPERATION.hpp - Specify how the nodes call each other and how processing is organized Copyright (C) Lumiera.org 2008, Hermann Vosseler This program is free software; you can redistribute it and/or modify it under the terms of the GNU 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /** @file nodeoperation.hpp ** Chunks of operation for invoking the rendernodes. ** This header defines the "glue" which holds together the render node network ** and enables to pull a result frames from the nodes. Especially, the aspect of ** buffer management is covered here. Each node has been preconfigured by the builder ** with a WiringDescriptor and a concrete type of a StateAdapter. These concrete ** StateAdapter objects are assembled out of the building blocks defined in this header, ** depending on the desired mode of operation. Any node can be built to ** - participate in the Caching or ignore the cache ** - actually process a result or just pull frames from a source ** - employ in-Place calculations or use separate in/out buffers ** Additionally, each node may have a given number of input/output pins, expecting to ** be provided with buffers holding a specific kind of data. ** ** \par composition of the StateAdapter ** For each individual ProcNode#pull() call, the WiringAdapter#callDown() builds an StateAdapter ** instance directly on the stack, holding the actual buffer pointers and state references. Using this ** StateAdapter, the predecessor nodes are pulled. The way these operations are carried out is encoded ** in the actual StateAdapter type known to the NodeWiring (WiringAdapter) instance. All of these actual ** StateAdapter types are built as implementing the engine::State interface, on top of the InvocationStateBase ** and inheriting from a chain of strategy classes (single inheritance, mostly \em no virtual functions). ** ** @see engine::ProcNode ** @see engine::StateProxy ** @see nodewiring.hpp interface for building/wiring the nodes ** */ #ifndef ENGINE_NODEOPERATION_H #define ENGINE_NODEOPERATION_H #include "proc/state.hpp" #include "proc/engine/procnode.hpp" #include "proc/engine/buffhandle.hpp" #include "proc/engine/bufftable.hpp" #include "proc/engine/nodewiringconfig.hpp" #include "lib/appconfig.hpp" namespace engine { /** * Adapter to shield the ProcNode from the actual buffer management, * allowing the processing function within ProcNode to use logical * buffer IDs. StateAdapter is created on the stack for each pull() * call, using setup/wiring data preconfigured by the builder. * Its job is to provide the actual implementation of the Cache * push / fetch and recursive downcall to render the source frames. */ class StateAdapter : public State { protected: State& parent_; State& current_; StateAdapter (State& callingProcess) : parent_ (callingProcess), current_(callingProcess.getCurrentImplementation()) { } virtual State& getCurrentImplementation () { return current_; } public: /* === proxying the State interface === */ virtual void releaseBuffer (BuffHandle& bh) { current_.releaseBuffer (bh); } virtual void is_calculated (BuffHandle const& bh) { current_.is_calculated (bh); } virtual BuffHandle fetch (FrameID const& fID) { return current_.fetch (fID); } // note: allocateBuffer() is choosen specifically based on the actual node wiring }; /** * Invocation context state. * A ref to this type is carried through the chain of NEXT::step() functions * which form the actual invocation sequence. The various operations in this sequence * access the context via the references in this struct, while also using the inherited * public State interface. The object instance actually used as Invocation is created * on the stack and parametrized according to the necessities of the invocation sequence * actually configured. Initially, this real instance is configured without BuffTable, * because the invocation may be short-circuited due to Cache hit. Otherwise, when * the invocation sequence actually prepares to call the process function of this * ProcNode, a buffer table chunk is allocated by the StateProxy and wired in. */ struct Invocation : StateAdapter { WiringDescriptor const& wiring; const uint outNr; BuffTable* buffTab; protected: /** creates a new invocation context state, without BuffTable */ Invocation (State& callingProcess, WiringDescriptor const& w, uint o) : StateAdapter(callingProcess), wiring(w), outNr(o), buffTab(0) { } const uint nrO() const { return wiring.getNrO(); } const uint nrI() const { return wiring.getNrI(); } const uint buffTabSize() const { return nrO()+nrI(); } /** setup the link to an externally allocated buffer table */ void setBuffTab (BuffTable* b) { this->buffTab = b; } bool buffTab_isConsistent () { return (buffTab) && (0 < buffTabSize()) && (nrO()+nrI() <= buffTabSize()) && (buffTab->inBuff == &buffTab->outBuff[nrO()] ) && (buffTab->inHandle == &buffTab->outHandle[nrO()]) ; } }; struct AllocBufferFromParent ///< using the parent StateAdapter for buffer allocations : Invocation { AllocBufferFromParent (State& sta, WiringDescriptor const& w, const uint outCh) : Invocation(sta, w, outCh) {} virtual BuffHandle allocateBuffer (BufferDescriptor const& bd) { return parent_.allocateBuffer(bd); } }; struct AllocBufferFromCache ///< using the global current State, which will delegate to Cache : Invocation { AllocBufferFromCache (State& sta, WiringDescriptor const& w, const uint outCh) : Invocation(sta, w, outCh) {} virtual BuffHandle allocateBuffer (BufferDescriptor const& bd) { return current_.allocateBuffer(bd); } }; /** * The real invocation context state implementation. It is created * by the NodeWiring (WiringDescriptor) of the processing node which * is pulled by this invocation, hereby using the internal configuration * information to guide the selecton of the real call sequence * * \par assembling the call sequence implementation * Each ProcNode#pull() call creates such a StateAdapter subclass on the stack, * with a concrete type according to the WiringDescriptor of the node to pull. * This concrete type encodes a calculation Strategy, which is assembled * as a chain of policy templates on top of OperationBase. For each of the * possible configuratons we define such a chain (see bottom of nodeoperation.hpp). * The WiringFactory defined in nodewiring.cpp actually drives the instantiation * of all those possible combinations. */ template class ActualInvocationProcess : public BufferProvider { public: ActualInvocationProcess (State& callingProcess, WiringDescriptor const& w, const uint outCh) : Invocation(callingProcess, w, outCh) { } /** contains the details of Cache query and recursive calls * to the predecessor node(s), eventually followed by the * ProcNode::process() callback */ BuffHandle retrieve () { return Strategy::step (*this); } }; /** * Collection of functions used to build up the invocation sequence. */ class OperationBase { }; template struct QueryCache : NEXT { BuffHandle step (Invocation& ivo) { BuffHandle fetched = ivo.fetch ( this->genFrameID (ivo)); if (fetched) return fetched; else return NEXT::step (ivo); } }; template struct AllocBufferTable : NEXT { BuffHandle step (Invocation& ivo) { BuffTableChunk buffTab (ivo.wiring, ivo.getBuffTableStorage()); ivo.setBuffTab(&buffTab); ASSERT (ivo.buffTab); ASSERT (ivo.buffTab_isConsistent()); return NEXT::step (ivo); } }; template struct PullInput : NEXT { BuffHandle step (Invocation& ivo) { BuffHandle * inH = ivo.buffTab->inHandle; BuffHandle::PBuff *inBuff = ivo.buffTab->inBuff; for (uint i = 0; i < ivo.nrI(); ++i ) { inBuff[i] = *(inH[i] = this->pullPredecessor(ivo,i)); // invoke predecessor // now Input #i is ready... } return NEXT::step (ivo); // note: passing down a ref to the ProcessInvocation } }; template struct ReadSource : NEXT { BuffHandle step (Invocation& ivo) { BuffHandle *inH = ivo.buffTab->inHandle; BuffHandle *outH = ivo.buffTab->outHandle; BuffHandle::PBuff *inBuff = ivo.buffTab->inBuff; BuffHandle::PBuff *outBuff = ivo.buffTab->outBuff; ASSERT (ivo.nrO() == ivo.nrI() ); for (uint i = 0; i < ivo.nrI(); ++i ) { inBuff[i] = outBuff[i] = *(inH[i] = outH[i] = this->getSource(ivo,i)); // now Input #i is ready... } return NEXT::step (ivo); } }; template struct AllocOutput : NEXT { BuffHandle step (Invocation& ivo) { ASSERT (ivo.buffTab); ASSERT (ivo.nrO() < ivo.buffTabSize()); BuffHandle *outH = ivo.buffTab->outHandle; BuffHandle::PBuff *outBuff = ivo.buffTab->outBuff; for (uint i = 0; i < ivo.nrO(); ++i ) { outBuff[i] = *(outH[i] = ivo.allocateBuffer (ivo.wiring.out[i].bufferType); // now Output buffer for channel #i is available... } return NEXT::step (ivo); } }; template struct ProcessData : NEXT { BuffHandle step (Invocation& ivo) { ASSERT (ivo.buffTab); ASSERT (ivo.buffTab_isConsistent()); ASSERT (this->validateBuffers(ivo)); // Invoke our own process() function, // providing the array of outBuffer+inBuffer ptrs ivo.wiring.processFunction (ivo.buffTab->outBuff); return NEXT::step (ivo); } }; template struct FeedCache : NEXT { BuffHandle step (Invocation& ivo) { // declare all Outputs as finished ivo.is_calculated(ivo.buffTab->outHandle, ivo.nrO()); return NEXT::step (ivo); } }; template struct ReleaseBuffers : NEXT /////////////////TODO: couldn't this be done automatically by BuffTab's dtor?? { ///////////////// this would require BuffHandle to be a smart ref.... BuffHandle step (Invocation& ivo) { // all buffers besides the required Output no longer needed this->releaseBuffers(ivo.buffTab->outHandle, ivo.buffTabSize(), ivo.outNr); return ivo.buffTab->outHandle[ivo.outNr]; } }; /* === declare the possible Assembly of these elementary steps === */ template struct SelectBuffProvider; template<> struct SelectBuffProvider : AllocBufferFromCache { }; template<> struct SelectBuffProvider : AllocBufferFromParent{ }; template<> struct SelectBuffProvider : AllocBufferFromCache { }; template<> struct SelectBuffProvider<> : AllocBufferFromParent{ }; template struct Strategy ; using lumiera::typelist::Config; template struct Strategy< Config > : QueryCache< AllocBufferTable< PullInput< AllocOutput< ProcessData< FeedCache< ReleaseBuffers< OperationBase > > > > > > > { }; template struct Strategy< Config > : AllocBufferTable< PullInput< AllocOutput< ProcessData< ReleaseBuffers< OperationBase > > > > > { }; template<> struct Strategy< Config<> > : AllocBufferTable< ReadSource< ReleaseBuffers< OperationBase > > > { }; template<> struct Strategy< Config > : Strategy< Config<> > { }; template<> struct Strategy< Config > : AllocBufferTable< ReadSource< AllocOutput< ProcessData< // wiring_.processFunction is supposed to do just buffer copying here ReleaseBuffers< OperationBase > > > > > { }; } // namespace engine #endif