Re: [PyOpenGL-Users] Code doesn't run on amd/ati hardware

[Mike C. F. <mcf...@vr...>]

On 13-01-15 11:57 AM, Tomasz Wesołowski wrote:
> Hello,
>
> On 15 January 2013 15:51, Mike C. Fletcher <mcf...@vr...> wrote:
>> Anyway, wrapping with a list should be fine, as it's what the API
>> actually expects.
> Just a little point- Wouldn't a .linesplit() on the string be more
> suitable than wrapping with a single-element list?

My understanding is that implementations are free to parse each element 
within the set as a separate set of statements, while some 
implementations decide to concat the whole and then parse it.  Thus some 
implementations (Intel) will accept a shader which is passed as a string 
(which gets turned into N single-character strings), while others (ATI) 
demand that each fragment be a valid set of statements in GLSL.

That said, I can't readily point to a spec saying that's how it is 
*supposed* to work, that just seems to be how it works in reality. The 
shader fragments are null-terminated, not line-terminated, so there's no 
reason I can see to use \n as a splitting character, and I'd rather not 
introduce any arbitrary changes there.  Particularly thinking of things 
like this:

matrix = [
     ...
];

which would, I'm guessing, blow up on any of the finicky implementations 
if we did line-by-line splits.

HTH,
Mike

-- 
________________________________________________
   Mike C. Fletcher
   Designer, VR Plumber, Coder
   http://www.vrplumber.com
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