Flash ActiveX: How to Load Movie from memory or resource or stream?

Question

I'm embedding a Flash ActiveX control in my C++ app (Flash.ocx, Flash10a.ocx, etc depending on your Flash version).

I can load an SWF file by calling LoadMovie(0, filename), but the file needs to physically reside in the disk. How to load the SWF from memory (or resource, or stream)? I'm sure there must be a way, because commercial solutions like f-in-box's feature Load flash movies from memory directly also uses Flash ActiveX control.

Answer 1

Being a flash guy I don't know any details on the C++ side, but if you made a request on the Flash side to a fake protocol, on the C side can you intercept that request and answer it with a data stream? I mean something like:

var mc:MovieClip = createEmptyMovieClip( "mc", 0 );
mc.loadMovie( "fakeprotocol://"+filename )

As long as the response looks (to Flash) like an HTTP stream, that ought to work. (Apologies in advance if the "intercept the request and return a data stream" is the part you're asking for help with.)

Answer 2

in addition.... Flash player promotes IPersistStorage. flash.QI IPersistStorage pStorage.load (mystorage_as_stream)

.. in theory.

Sorry for the above.. I intended to post Flash player promotes IPersistStreamInit. flash.QI IPersistStreamInit pStream.load (my_stream)

Michael

Answer 3

This method don't work when you try to load a movie via the MovieclipLoader or LoadMovie from another movie!!!

The result is to replace the calling SWF file!! ...so this method work only for loading the base file.

Someone know a better method that work also with MovieClipLoader and LoadMovie? Thanks.

Answer 4

To spare you some typing. It works for me in this way (just works not extensively tested):

void flash_load_memory(FlashWidget* w, void* data, ULONG size) {
        FlashMemoryStream fStream = FlashMemoryStream(data, size);
        IPersistStreamInit* psStreamInit = NULL;
        w->mFlashInterface->QueryInterface(IID_IPersistStreamInit,(LPVOID*) &psStreamInit);
        if(psStreamInit) {
            psStreamInit->InitNew();
            psStreamInit->Load((LPSTREAM)&fStream);
            psStreamInit->Release();
        }
    }

class FlashMemoryStream : IStream {
    public:
        FlashMemoryStream(void* data,ULONG size) {
            this->data = data;
            this->size = size;
            this->pos = 0;
        }

        HRESULT STDMETHODCALLTYPE QueryInterface(REFIID riid, LPVOID* ppv) {
            return E_NOTIMPL;
        }

        ULONG STDMETHODCALLTYPE AddRef() {  
            return E_NOTIMPL;
        }

        ULONG STDMETHODCALLTYPE Release() {  
            return E_NOTIMPL;
        }

        // IStream methods
        STDMETHOD(Read) (void *pv,ULONG cb,ULONG *pcbRead) {
            if(pos == 0 && cb == 4) {
                memcpy(pv,"fUfU",4);
                pos += 4;
                return S_OK;
            }
            else if(pos == 4 && cb == 4) {
                memcpy(pv,&size,4);
                size += 8;
                pos += 4;
                return S_OK;
            }
            else {
                if(pos + cb > size) cb = size - pos;
                if(cb == 0) return S_FALSE;
                memcpy(pv,(char*)data + pos - 8,cb);
                if(pcbRead) (*pcbRead) = cb;
                pos += cb;
                return S_OK;
            }
        }

        STDMETHOD(Write) (void const *pv,ULONG cb,ULONG *pcbWritten) { return E_NOTIMPL; }
        STDMETHOD(Seek) (LARGE_INTEGER dlibMove,DWORD dwOrigin,ULARGE_INTEGER *plibNewPosition) { return E_NOTIMPL; }
        STDMETHOD(SetSize) (ULARGE_INTEGER libNewSize) { return E_NOTIMPL; }
        STDMETHOD(CopyTo) (IStream *pstm,ULARGE_INTEGER cb,ULARGE_INTEGER *pcbRead,ULARGE_INTEGER *pcbWritten) { return E_NOTIMPL; }
        STDMETHOD(Commit) (DWORD grfCommitFlags) { return E_NOTIMPL; }
        STDMETHOD(Revert) (void) { return E_NOTIMPL; }
        STDMETHOD(LockRegion) (ULARGE_INTEGER libOffset,ULARGE_INTEGER cb,DWORD dwLockType) { return E_NOTIMPL; }
        STDMETHOD(UnlockRegion) (ULARGE_INTEGER libOffset,ULARGE_INTEGER cb,DWORD dwLockType) { return E_NOTIMPL; }
        STDMETHOD(Stat) (STATSTG *pstatstg,DWORD grfStatFlag) { return E_NOTIMPL; }
        STDMETHOD(Clone) (IStream **ppstm) { return E_NOTIMPL; }

        void* data;
        ULONG size;
        ULONG pos;
    };