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DirectFB data from memory buffer

I need a very fast way to display a data buffer for the screen. At first I tried accessing the linux framebuffer, and that turned out to be nice. Then I learned about DirectFB, and I liked the additional features it provides (for example, quick memcpy, resizing images on the fly, no need for additional code, etc.). But then I fell into the trap - all examples for images loaded from files. As far as I can tell, there are no examples / tutorials for my type of "DataBuffer". After looking at the documentation and source code, I was able to compile something like this:

DFBSurfaceDescription sdsc;
DFBDataBufferDescription ddsc;
DFBDataBufferDescriptionFlags ddscf = (DFBDataBufferDescriptionFlags)DBDESC_MEMORY;
IDirectFBDataBuffer *dbuffer;
IDirectFBImageProvider *provider;

ddsc.flags = ddscf;
ddsc.file = NULL;
ddsc.memory.data = m_z;
ddsc.memory.length = 640*480;

DFBCHECK (DirectFBInit (&argc, &argv));
DFBCHECK (DirectFBCreate (&dfb));
DFBCHECK (dfb->SetCooperativeLevel (dfb, DFSCL_FULLSCREEN));
sdsc.flags = DSDESC_CAPS;
sdsc.caps  = (DFBSurfaceCapabilities)(DSCAPS_PRIMARY | DSCAPS_FLIPPING);
DFBCHECK (dfb->CreateSurface( dfb, &sdsc, &primary ));
DFBCHECK (primary->GetSize (primary, &screen_width, &screen_height));

DFBCHECK (dfb->CreateDataBuffer(dfb, &ddsc, &dbuffer));
DFBCHECK (dbuffer->CreateImageProvider(dbuffer, &provider));
DFBCHECK (provider->GetSurfaceDescription (provider, &sdsc));

DFBCHECK (dfb->CreateSurface( dfb, &sdsc, &fbwindow ));
DFBCHECK (provider->RenderTo (provider, fbwindow, NULL));
provider->Release (provider);

, DataBuffer DFB, ImageProvider DataBuffer . , , :

(#) DirectFBError [dbuffer->CreateImageProvider(dbuffer, &provider)]: No (suitable) implementation found!

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, DataBuffer. , DSDESC_PREALLOCATED flasg . Blit() Flip() . , , DirectFB: 32- RGBA , 32- ARGB - , .

:

  dsc.width = screen_width;
  dsc.height = screen_height;
  dsc.flags = DSDESC_HEIGHT | DSDESC_WIDTH | DSDESC_PREALLOCATED | DSDESC_PIXELFORMAT;
  dsc.caps = DSCAPS_NONE;
  dsc.pixelformat = DSPF_ARGB;
  dsc.preallocated[0].data = buffer;      // Buffer is your data
  dsc.preallocated[0].pitch = dsc.width*4;
  dsc.preallocated[1].data = NULL;
  dsc.preallocated[1].pitch = 0;

  DFBCHECK (dfb->CreateSurface( dfb, &dsc, &imageSurface ));
  DFBCHECK (primary->Blit(primary, imageSurface, NULL, 0, 0));
  DFBCHECK (primary->Flip(primary, NULL, DSFLIP_ONSYNC));

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+7

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// Variables
DFBDataBufferDescription ddsc;
DFBSurfaceDescription sdsc;
IDirectFBDataBuffer *buffer;
IDirectFBImageProvider *image_provider;

// The surface that will contain the rendered image
IDirectFBSurface *surface;                      

// create a data buffer for memory
ddsc.flags = DBDESC_MEMORY;
ddsc.memory.data = data;
ddsc.memory.length = dataLength;
DFBCHECK(directFB->CreateDataBuffer(directFB, &ddsc, &buffer));

// Create the image provider, surface description and surface itself
DFBCHECK(buffer->CreateImageProvider(buffer, &image_provider));
DFBCHECK(image_provider->GetSurfaceDescription(image_provider, &sdsc));
DFBCHECK(directFB->CreateSurface(directFB, &sdsc, &surface ));

// Now render the image onto the surface
DFBCHECK(image_provider->RenderTo(image_provider, surface, NULL));

// Release 
image_provider->Release(image_provider);
buffer->Release(buffer);

data​​strong > - unsigned char, (: "xxd -i image.jpg > image.h" ), datalength - unsigned int . blit , , "" .

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