Function canvas::webgl_thread::prepare_pixels

fn prepare_pixels(
    internal_format: TexFormat,
    data_type: TexDataType,
    size: Size2D<u32>,
    unpacking_alignment: u32,
    alpha_treatment: Option<AlphaTreatment>,
    y_axis_treatment: YAxisTreatment,
    pixel_format: Option<PixelFormat>,
    pixels: Cow<'_, [u8]>
) -> Cow<'_, [u8]>