Function convertToRGBAF

Source/Falcor/Utils/Image/Bitmap.cpp:212–243

* Converts 96bpp to 128bpp RGBA without clamping. * Note that we can't use FreeImage_ConvertToRGBAF() as it clamps to [0,1]. */

 * Note that we can't use FreeImage_ConvertToRGBAF() as it clamps to [0,1].
 */
static FIBITMAP* convertToRGBAF(FIBITMAP* pDib)
{
    const unsigned width = FreeImage_GetWidth(pDib);
    const unsigned height = FreeImage_GetHeight(pDib);

    auto pNew = FreeImage_AllocateT(FIT_RGBAF, width, height);
    FreeImage_CloneMetadata(pNew, pDib);

    const unsigned src_pitch = FreeImage_GetPitch(pDib);
    const unsigned dst_pitch = FreeImage_GetPitch(pNew);

    const BYTE* src_bits = (BYTE*)FreeImage_GetBits(pDib);
    BYTE* dst_bits = (BYTE*)FreeImage_GetBits(pNew);

    for (unsigned y = 0; y < height; y++)
    {
        const FIRGBF* src_pixel = (FIRGBF*)src_bits;
        FIRGBAF* dst_pixel = (FIRGBAF*)dst_bits;

        for (unsigned x = 0; x < width; x++)
        {
            // Convert pixels directly, while adding a "dummy" alpha of 1.0
            dst_pixel[x].red = src_pixel[x].red;
            dst_pixel[x].green = src_pixel[x].green;
            dst_pixel[x].blue = src_pixel[x].blue;
            dst_pixel[x].alpha = 1.0F;
        }
        src_bits += src_pitch;
        dst_bits += dst_pitch;
    }
    return pNew;
}

/**
 * Converts 96/128bpp to 64bpp RGBA floating-point image.