[VDPAU] Interpretation of the VdpOutputSurfaceRender{Bitmap, Output}Surface spec

[Emil Velikov]

On 26/08/14 18:57, Stephen Warren wrote:
> Emil Velikov wrote at Tuesday, August 26, 2014 11:31 AM:
>> Hello list,
>>
>> Having a closer look at the specification [1] of the two functions one can
>> observe the following
>>
>>   "...If source_surface is NULL..."
>> yet it seems that the type of source_surface is a 32 bit unsigned:
>>
>>   typedef uint32_t VdpBitmapSurface
>>   typedef uint32_t VdpOutputSurface
>>
>> Which begs the question - by NULL do the spec actually mean 0 or
>> VDP_INVALID_HANDLE (0xffffffffU) ?
> 
> The spec should say VDP_INVALID_HANDLE not NULL.
> 
>> I'm suspecting that either interpretation
>> might cause buggy behaviour in some (any?) programs that depends on the
>> particular functionality.
> 
> Given that the NVDIA implementation almost certainly is coded to actually
> implement a check for VDP_INVALID_HANDLE not a check for NULL, I hope that
> applications are already passing the expected value here, or they'd be
> experiencing unexpected behavior here, or the API is simply returning an
> error.
> 
Ack. Thank you for the prompt and comprehensive reply Stephen.

Hope that we'll get the documentation updated so that people like me are not
as easily confused :)

-Emil