Function imgui_sys::ImFontAtlas_GetTexDataAsAlpha8

pub unsafe extern fn ImFontAtlas_GetTexDataAsAlpha8(
    atlas: *mut ImFontAtlas, 
    out_pixels: *mut *mut c_uchar, 
    out_width: *mut c_int, 
    out_height: *mut c_int, 
    out_bytes_per_pixel: *mut c_int
)