Re: [2/3] gdiplus: If a 32-bit dib is selected in an hdc, use the dib directly.

[Alexandre Julliard]

Vincent Povirk <madewokherd(a)gmail.com> writes:
> @@ -2264,6 +2266,41 @@ GpStatus WINGDIPAPI GdipCreateFromHDC2(HDC hdc, HANDLE hDevice, GpGraphics **gra
>      if(graphics == NULL)
>          return InvalidParameter;
>
> +    hbm = GetCurrentObject(hdc, OBJ_BITMAP);
> +    if (hbm && GetObjectW(hbm, sizeof(dib), &dib) && dib.dsBm.bmBitsPixel == 32)
> +    {
> +        /* Make a bitmap object so we can use the alpha channel */
> +        GpBitmap *bitmap;
> +        DWORD height, stride;
> +        BYTE *bits;
> +
> +        height = abs(dib.dsBmih.biHeight);
> +        stride = dib.dsBmih.biWidth * 4;
> +
> +        if(dib.dsBmih.biHeight > 0) /* bottom-up */
> +        {
> +            bits = (BYTE*)dib.dsBm.bmBits + (height - 1) * stride;
> +            stride = -dib.dsBmih.biWidth * 4;
> +        }
> +        else
> +            bits = dib.dsBm.bmBits;
> +
> +        retval = GdipCreateBitmapFromScan0(dib.dsBmih.biWidth, height, stride,
> +                                           PixelFormat32bppPARGB, bits, &bitmap);

This won't work, you won't get a negative height with GetObject, and you
won't get DIB info at all for DDBs. Also not all DIBs are in PARGB format.

-- 
Alexandre Julliard
julliard(a)winehq.org