Quoting Denis Oliver Kropp ([EMAIL PROTECTED]):
> Quoting Sarfraz Nawaz ([EMAIL PROTECTED]):
> > >
> > There's no method for drawing a single pixel, because developers shouldn't
> > use such a method. Drawing several pixels with one call for each pixel is
> > very much overhead. Instead you should lock the surface data via Lock() and
> > write all pixels yourself.
> >
> > If you like you can use FillRectangle() with size 1x1. It has the same overhead
> > as a DrawPixel() method would have.
> > >
> >
> > Can you explain the locking and writing pixels approach a bit further. I
> > would be writing around 400 pixels in one go and then blitting the surfaces.
>
> You have to call Lock() and get a data pointer and the pitch (number of bytes
> to add to the data pointer to get to the next row).
>
> Furthermore it depends on the pixel format how your pixels have to be written.
>
> Example (not checked if it compiles):
>
> DFBResult fill_surface( IDirectFBSurface *surface, __u8 r, __u8 g, __u8 b )
> {
> DFBResult ret;
> void *data;
> int pitch;
> int x, y, width, height;
> DFBSurfacePixelFormat format;
>
> ret = surface->Lock( surface, DSLF_WRITE, &data, &pitch );
> if (ret) {
> DirectFBError( "IDirectFBSurface::Lock() failed", ret );
> return ret;
> }
>
> surface->GetSize( surface, &width, &height );
> surface->GetPixelFormat( surface, &format );
>
> switch (format) {
> case DSPF_RGB16:
> for (y=0; y<height; y++) {
> __u16 *dst = data + y * pitch;
>
> for (x=0; x<width; x++)
> dst[x] = PIXEL_RGB16( r, g, b );
You can copy these pixel macros from "DirectFB/src/gfx/convert.h".
--
Best regards,
Denis Oliver Kropp
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